Patent Publication Number: US-2022217290-A1

Title: Imaging device

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation of U.S. patent application Ser. No. 17/058,029 filed 23 Nov. 2020, which is a national stage application under 35 U.S.C. 371 and claims the benefit of PCT Application No. PCT/JP2019/020587 having an international filing date of 24 May 2019, which designated the United States, which PCT application claimed the benefit of Japanese Patent Application No. 2018-110252, filed 8 Jun. 2018, the entire disclosures of each of which are incorporated herein by reference. 
    
    
     TECHNICAL FIELD 
     The present disclosure relates to an imaging device, and particularly to an imaging device capable of achieving miniaturization and height reduction of a device configuration and imaging while reducing generation of a flare and a ghost. 
     BACKGROUND ART 
     High pixelization, miniaturization, and height reduction of a solid-state imaging element included in a mobile terminal apparatus equipped with a camera, a digital still camera, and the like have been progressing in recent years. 
     With high pixelization and miniaturization of a camera, a lens and a solid-state imaging element are located closer to each other on an optical axis. Accordingly, an infrared cut filter is generally disposed in the vicinity of the lens. 
     For example, there has been proposed a technology which achieves miniaturization of a solid-state imaging element by disposing a lens, which is included in a lens group constituted by a plurality of lenses and is located in a lowermost layer, on the solid-state imaging element. 
     CITATION LIST 
     Patent Literature 
     [PTL 1] 
     
         
         JP 2015-061193A 
       
    
     SUMMARY 
     Technical Problem 
     However, in the case of the configuration where the lens in the lowermost layer is disposed on the solid-state imaging element, this configuration contributes to miniaturization and height reduction of the device configuration, but decreases the distance between the infrared cut filter and the lens. Accordingly, a flare or a ghost is caused by internal diffused reflection resulting from light reflection. 
     The present disclosure has been developed in consideration of the aforementioned circumstances, and particularly achieves miniaturization and height reduction of a solid-state imaging element, and reduces generation of a flare and a ghost. 
     Solution to Problem 
     An imaging device according to one aspect of the present disclosure is directed to an imaging device including a solid-state imaging element that generates a pixel signal by photoelectric conversion according to a light amount of incident light, an integrated configuration unit that integrates a function of fixing the solid-state imaging element and a function of cutting off infrared light of the incident light, and a lens group that includes a plurality of lenses and focuses the incident light on a light receiving surface of the solid-state imaging element. The integrated configuration unit deploys a lowermost layer lens of the lens group in a foremost stage in a direction for receiving the incident light, the lowermost layer lens constituting a lowermost layer with respect to an incident direction of the incident light. The lowermost layer lens is an aspherical and recessed lens, an effective region for converging the incident light on the solid-state imaging element being defined, a size of the effective region in a vertical direction with respect to the incident light being smaller than a size of an external shape of the lowermost layer lens, the size of the external shape of the lowermost layer lens in the vertical direction with respect to the incident light being smaller than a size of the solid-state imaging element. 
     According to the one aspect of the present disclosure, a pixel signal is generated by photoelectric conversion according to the light amount of the incident light, by using the solid-state imaging element. The incident light is focused on the light receiving surface of the solid-state imaging element, by using the lens group including the plurality of lenses. The integrated configuration unit that integrates the function of fixing the solid-state imaging element and the function of cutting off infrared light of the incident light deploys the lowermost layer lens of the lens group in the foremost stage in the direction for receiving the incident light. The lowermost layer lens is an aspherical and recessed lens and constitutes the lowermost layer with respect to the incident direction of the incident light. The effective region for converging the incident light on the solid-state imaging element is defined. The size of the effective region in the vertical direction with respect to the incident light is smaller than the size of the external shape of the lowermost layer lens. The size of the external shape of the lowermost layer lens in the vertical direction with respect to the incident light is smaller than the size of the solid-state imaging element. 
     Advantageous Effects of Invention 
     According to one aspect of the present disclosure, miniaturization and height reduction of a device configuration for a solid-state imaging element, and also reduction of generation of a flare and a ghost are particularly achievable. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         FIG. 1  is a diagram explaining a configuration example of an imaging device according to a first embodiment of the present disclosure. 
         FIG. 2  is an external appearance schematic diagram of an integrated configuration unit including a solid-state imaging element of the imaging device of  FIG. 1 . 
         FIG. 3  depicts diagrams explaining a substrate configuration of the integrated configuration unit. 
         FIG. 4  is a diagram depicting a circuit configuration example of a laminated substrate. 
         FIG. 5  is a diagram depicting an equivalent circuit of pixels. 
         FIG. 6  is a diagram depicting a detailed structure of the laminated substrate. 
         FIG. 7  is a diagram explaining that a ghost and a flare caused by internal diffused reflection are not generated in the imaging device of  FIG. 1 . 
         FIG. 8  is a diagram explaining that a ghost and a flare caused by internal diffused reflection are not generated in an image captured by the imaging device of  FIG. 1 . 
         FIG. 9  is a diagram explaining a configuration example of an imaging device according to a second embodiment of the present disclosure. 
         FIG. 10  is a diagram explaining that a ghost and a flare caused by internal diffused reflection are not generated in the imaging device of  FIG. 9 . 
         FIG. 11  is a diagram explaining a configuration example of an imaging device according to a third embodiment of the present disclosure. 
         FIG. 12  is a diagram explaining a configuration example of an imaging device according to a fourth embodiment of the present disclosure. 
         FIG. 13  is a diagram explaining a configuration example of an imaging device according to a fifth embodiment of the present disclosure. 
         FIG. 14  is a diagram explaining a configuration example of an imaging device according to a sixth embodiment of the present disclosure. 
         FIG. 15  is a diagram explaining a configuration example of an imaging device according to a seventh embodiment of the present disclosure. 
         FIG. 16  is a diagram explaining a configuration example of an imaging device according to an eighth embodiment of the present disclosure. 
         FIG. 17  is a diagram explaining a configuration example of an imaging device according to a ninth embodiment of the present disclosure. 
         FIG. 18  is a diagram explaining a configuration example of an imaging device according to a tenth embodiment of the present disclosure. 
         FIG. 19  is a diagram explaining a configuration example of an imaging device according to an eleventh embodiment of the present disclosure. 
         FIG. 20  is a diagram explaining a configuration example of an imaging device according to a twelfth embodiment of the present disclosure. 
         FIG. 21  is a diagram explaining a configuration example of an imaging device according to a thirteenth embodiment of the present disclosure. 
         FIG. 22  is a diagram explaining a configuration example of an imaging device according to a fourteenth embodiment of the present disclosure. 
         FIG. 23  is a diagram explaining a configuration example of an imaging device according to a fifteenth embodiment of the present disclosure. 
         FIG. 24  is a diagram explaining modified examples of a lens external shape of  FIG. 23 . 
         FIG. 25  is a diagram explaining modified examples of a structure of a lens end portion of  FIG. 23 . 
         FIG. 26  is another diagram explaining modified examples of the structure of the lens end portion of  FIG. 23 . 
         FIG. 27  is a still another diagram explaining a modified example of the structure of the lens end portion of  FIG. 23 . 
         FIG. 28  is a yet another diagram explaining modified examples of the structure of the lens end portion of  FIG. 23 . 
         FIG. 29  is a diagram explaining a configuration example of an imaging device according to a sixteenth embodiment of the present disclosure. 
         FIG. 30  is a diagram explaining a manufacturing method of the imaging device of  FIG. 29 . 
         FIG. 31  is a diagram explaining modified examples of an individualized cross section of a configuration example of  FIG. 29 . 
         FIG. 32  is a diagram explaining a manufacturing method of an imaging device in an upper left part of  FIG. 31 . 
         FIG. 33  is a diagram explaining a manufacturing method of an imaging device in a lower left part of  FIG. 31 . 
         FIG. 34  is a diagram explaining a manufacturing method of an imaging device in an upper right part of  FIG. 31 . 
         FIG. 35  is a diagram explaining a manufacturing method of an imaging device in a lower right part of  FIG. 31 . 
         FIG. 36  is a diagram explaining modified examples which add an anti-reflection film to the configuration of  FIG. 29 . 
         FIG. 37  is a diagram explaining a modified example which adds an anti-reflection film to a side surface portion of the configuration of  FIG. 29 . 
         FIG. 38  is a diagram explaining a configuration example of an imaging device according to a seventeenth embodiment of the present disclosure. 
         FIG. 39  is a diagram explaining a condition of a thickness of a lens which is miniaturized, lightweight, and capable of capturing a high-resolution image. 
         FIG. 40  is a diagram explaining stress distributions applied to an AR coating on the lens during loading of implementation reflow heat corresponding to a lens shape. 
         FIG. 41  is a diagram explaining a modified example of a lens shape of  FIG. 39 . 
         FIG. 42  is a diagram explaining a shape of a two-stage side surface lens of  FIG. 41 . 
         FIG. 43  is a diagram explaining modified examples of the shape of the two-stage side surface lens of  FIG. 41 . 
         FIG. 44  is a diagram explaining stress distributions applied to an AR coating on the two-stage side surface lens of  FIG. 41  during loading of implementation reflow heat. 
         FIG. 45  is a diagram explaining maximum values of stress distributions applied to the AR coating on the lens of  FIG. 44  during loading of implementation reflow heat. 
         FIG. 46  is a diagram explaining a manufacturing method of an imaging device according to an eighteenth embodiment of the present disclosure. 
         FIG. 47  is a diagram explaining modified examples of the manufacturing method of  FIG. 46 . 
         FIG. 48  is a diagram explaining a manufacturing method of the two-stage side surface lens. 
         FIG. 49  is a diagram explaining a modified example of the manufacturing method of the two-stage side surface lens. 
         FIG. 50  is a diagram explaining adjustment of angles formed by average surfaces of a side surface, adjustment of surface roughness, and addition of a hemming bottom portion in the manufacturing method of the two-stage side surface lens of  FIG. 49 . 
         FIG. 51  is a diagram explaining a configuration example of an imaging device according to a nineteenth embodiment of the present disclosure. 
         FIG. 52  is a diagram explaining examples of an alignment mark of  FIG. 51 . 
         FIG. 53  is a diagram explaining an application example of the alignment mark of  FIG. 51 . 
         FIG. 54  is a diagram explaining a configuration example of an imaging device according to a twentieth embodiment of the present disclosure. 
         FIG. 55  is a diagram explaining stress distributions applied to an AR coating during loading of implementation reflow heat in a case where the AR coating is formed in an entire surface and in different cases. 
         FIG. 56  is a diagram explaining a configuration example of an imaging device according to a twenty-first embodiment of the present disclosure. 
         FIG. 57  is a diagram explaining examples where a light shielding film is formed on a side surface in a configuration connecting a lens and a bank. 
         FIG. 58  is a block diagram depicting a configuration example of an imaging device as an electronic apparatus to which a camera module of the present disclosure is applied. 
         FIG. 59  is a diagram explaining use examples of the camera module to which the technology of the present disclosure is applied. 
         FIG. 60  is a view depicting an example of a schematic configuration of an endoscopic surgery system. 
         FIG. 61  is a block diagram depicting an example of a functional configuration of a camera head and a camera control unit (CCU). 
         FIG. 62  is a block diagram depicting an example of schematic configuration of a vehicle control system. 
         FIG. 63  is a diagram of assistance in explaining an example of installation positions of an outside-vehicle information detecting section and an imaging section. 
     
    
    
     DESCRIPTION OF EMBODIMENTS 
     Preferred embodiments according to the present disclosure will be hereinafter described in detail with reference to the accompanying drawings. Note that constituent elements having substantially identical functional configurations are given identical reference signs in the present description and the drawings, and repeated description is thus omitted. 
     Modes for carrying out the present disclosure (hereinafter referred to as embodiments) will be hereinafter described. Note that the description will be presented in a following order. 
     1. First Embodiment 
     2. Second Embodiment 
     3. Third Embodiment 
     4. Fourth Embodiment 
     5. Fifth Embodiment 
     6. Sixth Embodiment 
     7. Seventh Embodiment 
     8. Eighth Embodiment 
     9. Ninth Embodiment 
     10. Tenth Embodiment 
     11. Eleventh Embodiment 
     12. Twelfth Embodiment 
     13. Thirteenth Embodiment 
     14. Fourteenth Embodiment 
     15. Fifteenth Embodiment 
     16. Sixteenth Embodiment 
     17. Seventeenth Embodiment 
     18. Eighteenth Embodiment 
     19. Nineteenth Embodiment 
     20. Twentieth Embodiment 
     21. Twenty-First Embodiment 
     22. Example of application to electronic apparatus 
     23. Use examples of solid-state imaging device 
     24. Example of application to endoscopic surgery system 
     25. Example of application to mobile body 
     1. First Embodiment 
     &lt;Configuration Example of Imaging Device&gt; 
     Described with reference to  FIG. 1  will be a configuration example of an imaging device which reduces generation of a ghost and a flare while achieving miniaturization and height reduction of a device configuration according to a first embodiment of the present disclosure. Note that  FIG. 1  is a side cross-sectional diagram of the imaging device. 
     An imaging device  1  of  FIG. 1  includes a solid-state imaging element  11 , a glass substrate  12 , an IRCF (infrared cut filter)  14 , a lens group  16 , a circuit board  17 , an actuator  18 , a connector  19 , and a spacer  20 . 
     The solid-state imaging element  11  is an image sensor constituted by what is generally called a CMOS (Complementary Metal Oxide Semiconductor), a CCD (Charge Coupled Device), or the like, and is fixed while electrically connected on the circuit board  17 . As described below with reference to  FIG. 4 , the solid-state imaging element  11  which includes a plurality of pixels arranged in an array generates a pixel signal corresponding to a light amount of incident light entering the solid-state imaging element  11  from an upper side in the figure after converged via the lens group  16  for each pixel, and outputs the generated signal as an image signal to the outside from the connector  19  via the circuit board  17 . 
     The glass substrate  12  is provided on an upper surface portion of the solid-state imaging element  11  in  FIG. 1  and is affixed by an adhesive (GLUE)  13  which is transparent, i.e., has substantially the same refractive index as that of the glass substrate  12 . 
     The IRCF  14  for cutting infrared light included in incident light is provided on an upper surface portion of the glass substrate  12  in  FIG. 1  and is affixed by an adhesive (GLUE)  15  which is transparent, i.e., has substantially the same refractive index as that of the glass substrate  12 . For example, the IRCF  14  includes a blue plate glass and cuts off (removes) infrared light. 
     In other words, the solid-state imaging element  11 , the glass substrate  12 , and the IRCF  14  are laminated, and affixed to each other by the transparent adhesives  13  and  15  to constitute an integrated configuration, and are connected to the circuit board  17 . Note that the solid-state imaging element  11 , the glass substrate  12 , and the IRCF  14  surrounded by a one-dot chain line in the figure are affixed to each other by the adhesives  13  and  15  having substantially the same refractive index to constitute an integrated configuration. Accordingly, the integrated configuration thus formed will be hereinafter also simply referred to as an integrated configuration unit  10 . 
     In addition, the IRCF  14  may be individualized in a manufacturing step of the solid-state imaging element  11  and then affixed onto the glass substrate  12 , or the large-sized IRCF  14  may be affixed onto the entire glass substrate  12  having a wafer shape and constituted by a plurality of the solid-state imaging elements  11  and then individualized in units of the solid-state imaging element  11 . Either of these methods may be adopted. 
     The spacer  20  is provided on the circuit board  17  in such a manner as to surround the whole of the integrated configuration constituted by the solid-state imaging element  11 , the glass substrate  12 , and the IRCF  14 . In addition, the actuator  18  is provided on the spacer  20 . The actuator  18  having a cylindrical configuration includes the lens group  16  which is built in the actuator  18  and constituted by a plurality of laminated lenses disposed inside the cylindrical shape, and drives the lens group  16  in an up-down direction in  FIG. 1 . 
     The actuator  18  thus configured achieves auto-focusing by moving the lens group  16  in the up-down direction in  FIG. 1  (a front-rear direction with respect to an optical axis) for focus adjustment such that an image of a not-depicted object is formed on an imaging surface of the solid-state imaging element  11  according to a distance to the object located in the upper side of the figure. 
     &lt;External Appearance Schematic Diagram&gt; 
     A configuration of the integrated configuration unit  10  will be subsequently described with reference to  FIGS. 2 to 6 .  FIG. 2  is an external appearance schematic diagram of the integrated configuration unit  10 . 
     The integrated configuration unit  10  depicted in  FIG. 2  is a semiconductor package including the packaged solid-state imaging element  11  which includes a laminated substrate constituted by a lamination of a lower substrate  11   a  and an upper substrate  11   b.    
     A plurality of solder balls  11   e  as back electrodes for electrically connecting with the circuit board  17  in  FIG. 1  is provided on the lower substrate  11   a  of the laminated substrate constituting the solid-state imaging element  11 . 
     Color filters  11   c  in R (red), G (green), or B (blue), and on-chip lenses  11   d  are provided on an upper surface of the upper substrate  11   b . Moreover, the upper substrate  11   b  is connected with the glass substrate  12  provided to protect the on-chip lens  11   d . This connection is made by a non-cavity structure via the adhesive  13  made of glass seal resin. 
     For example, as depicted in A of  FIG. 3 , a pixel region  21  where pixel units performing photoelectric conversion are two-dimensionally arranged in an array, and a control circuit  22  for controlling the pixel units are provided on the upper substrate  11   b . On the other hand, a logic circuit  23  such as a signal processing circuit for processing pixel signals output from the pixel units is provided on the lower substrate  11   a.    
     Alternatively, as depicted in B of  FIG. 3 , only the pixel region  21  may be provided on the upper substrate  11   b , while the control circuit  22  and the logic circuit  23  may be provided on the lower substrate  11   a.    
     As described above, the logic circuit  23 , or both the control circuit  22  and the logic circuit  23  are formed and laminated on the lower substrate  11   a  different from the upper substrate  11   b  including the pixel region  21 . In this manner, the size of the imaging device  1  can be more reduced than that size in a case where the pixel region  21 , the control circuit  22 , and the logic circuit  23  are disposed on one semiconductor substrate in a flat surface direction. 
     In the following description, the upper substrate  11   b  where at least the pixel region  21  is provided will be referred to as a pixel sensor substrate  11   b , while the lower substrate  11   a  where at least the logic circuit  23  is provided will be referred to as a logic substrate  11   a.    
     &lt;Configuration Example of Laminated Substrate&gt; 
       FIG. 4  depicts a circuit configuration example of the solid-state imaging element  11 . 
     The solid-state imaging element  11  includes a pixel array unit  33  where pixels  32  are arranged in a two-dimensional array, a vertical driving circuit  34 , column signal processing circuits  35 , a horizontal driving circuit  36 , an output circuit  37 , a control circuit  38 , and an input/output terminal  39 . 
     Each of the pixels  32  includes a photodiode as a photoelectric conversion element and a plurality of pixel transistors. A circuit configuration example of the pixels  32  will be described below with reference to  FIG. 5 . 
     In addition, each of the pixels  32  may have a shared pixel structure. This pixel shared structure includes a plurality of photodiodes, a plurality of transfer transistors, one shared floating diffusion (floating diffusion region), and shared other pixel transistors one for each. In other words, according to the configuration of the shared pixels, photodiodes and transfer transistors constituting a plurality of unit pixels have other shared pixel transistors one for each. 
     The control circuit  38  receives an input clock, and data for commanding an operation mode or the like, and also outputs data such as internal information associated with the solid-state imaging element  11 . Specifically, the control circuit  38  generates a clock signal and a control signal as references for operations of the vertical driving circuit  34 , the column signal processing circuits  35 , the horizontal driving circuit  36 , and the like on the basis of a vertical synchronized signal, a horizontal synchronized signal, and a master clock. Thereafter, the control circuit  38  outputs the generated clock signal and control signal to the vertical driving circuit  34 , the column signal processing circuits  35 , the horizontal driving circuit  36 , and the like. 
     The vertical driving circuit  34  is constituted by a shift register, for example, and selects a designated pixel driving wire  40 , supplies a pulse to the selected pixel driving wire  40  to drive the pixels  32 , and drives the pixels  32  in units of row. Specifically, the vertical driving circuit  34  sequentially performs selective scanning of the respective pixels  32  of the pixel array unit  33  in units of row in the vertical direction, and supplies pixel signals based on signal charges generated by photoelectric conversion units of the respective pixels  32  according to light reception amounts, and supplies the generated pixel signals to the column signal processing circuits  35  via vertical signal lines  41 . 
     Each of the column signal processing circuits  35  is disposed for the corresponding one of the columns of the pixels  32 , and performs signal processing such as noise removal for signals output from one row of the pixels  32  for each pixel column. For example, each of the column signal processing circuits  5  performs signal processing such as CDS (Correlated Double Sampling) and AD conversion for removing fixed pattern noise peculiar to the pixels. 
     The horizontal driving circuit  36  is constituted by a shift register, for example, and sequentially selects each of the column signal processing circuits  35  by sequentially outputting a horizontal scanning pulse, and causes each of the column signal processing circuits  35  to output a pixel signal to the horizontal signal line  42 . 
     The output circuit  37  performs signal processing for signals sequentially supplied from the respective column signal processing circuits  35  via the horizontal signal line  42 , and outputs the processed signals. For example, the output circuit  37  performs only buffering in some cases, or performs black level adjustment, column variation correction, various digital signal processes, and the like in other cases. The input/output terminal  39  exchanges signals with the outside. 
     The solid-state imaging element  11  configured as above is a CMOS image sensor of what is generally called a column AD system where the column signal processing circuit  35  performing a CDS process and an AD conversion process is disposed for each of the pixel columns. 
     &lt;Circuit Configuration Example of Pixel&gt; 
       FIG. 5  depicts an equivalent circuit of the pixel  32 . 
     The pixel  32  depicted in  FIG. 5  has a configuration for achieving an electronic type global shutter function. 
     The pixel  32  includes a photodiode  51  as a photoelectric conversion element, a first transfer transistor  52 , a memory unit (MEM)  53 , a second transfer transistor  54 , an FD (floating diffusion region)  55 , a reset transistor  56 , an amplification transistor  57 , a selection transistor  58 , and a discharge transistor  59 . 
     The photodiode  51  is a photoelectric conversion unit which generates a charge corresponding to a light reception amount (signal charge) and accumulates the charge. An anode terminal of the photodiode  51  is grounded, while a cathode terminal of the photodiode  51  is connected to the memory unit  53  via the first transfer transistor  52 . Further, the cathode terminal of the photodiode  51  is also connected to the discharge transistor  59  for discharging an unnecessary charge. 
     The first transfer transistor  52  reads a charge generated by the photodiode  51  and transfers the charge to the memory unit  53  when the first transfer transistor  52  is turned on by a transfer signal TRX. The memory unit  53  is a charge retaining unit which temporarily retains a charge until transfer of the charge to the FD  55 . 
     The second transfer transistor  54  reads a charge retained by the memory unit  53  and transfers the charge to the FD  55  when the second transfer transistor  54  is turned on by a transfer signal TRG. 
     The FD  55  is a charge retaining unit which retains a charge read from the memory unit  53  to read the charge as a signal. The reset transistor  56  resets a potential of the FD  55  by discharging a charge accumulated in the FD  55  to a constant voltage source VDD when the reset transistor  56  is turned on by a reset signal RST. 
     The amplification transistor  57  outputs a pixel signal corresponding to a potential of the FD  55 . Specifically, the amplification transistor  57  constitutes a source follower circuit in cooperation with a load MOS  60  which is a constant current source. A pixel signal indicating a level of a charge accumulated in the FD  55  is output to the column signal processing circuit  35  ( FIG. 4 ) from the amplification transistor  57  via the selection transistor  58 . For example, the load MOS  60  is disposed within the column signal processing circuit  35 . 
     The selection transistor  58  is turned on when the pixel  32  is selected by a selection signal SEL, and outputs a pixel signal of the pixel  32  to the column signal processing circuit  35  via the vertical signal line  41 . 
     The discharge transistor  59  discharges an unnecessary load accumulated in the photodiode  51  to the constant voltage source VDD when the discharge transistor  59  is turned on by a discharge signal OFG. 
     The transfer signals TRX and TRG, the reset signal RST, the discharge signal OFG, and the selection signal SEL are supplied from the vertical driving circuit  34  via the pixel driving wire  40 . 
     Operation of the pixels  32  will be briefly described. 
     Initially, the discharge transistors  59  are turned on by supplying the high-level discharge signal OFG to the discharge transistors  59  before an exposure start. Thereafter, charges accumulated in the photodiodes  51  are discharged to the constant voltage source VDD, and the photodiodes  51  of all the pixels are reset. 
     When the discharge transistors  59  are turned off by the low-level discharge signal OFG after the reset of the photodiodes  51 , exposure of all the pixels of the pixel array unit  33  is started. 
     After an elapse of a predetermined exposure time determined beforehand, the first transfer transistors  52  of all the pixels of the pixel array unit  33  are turned on by the transfer signal TRX, and charges accumulated in the photodiodes  51  are transferred to the memory units  53 . 
     After the first transfer transistors  52  are turned off, the charges retained in the memory units  53  of the respective pixels  32  are sequentially read by the column signal processing circuits  35  in units of row. In the reading operation, the second transfer transistor  54  of the pixel  32  in the reading row is turned on by the transfer signal TRG, and the charge retained in the memory unit  53  is transferred to the FD  55 . Thereafter, the selection transistor  58  is turned on by the selection signal SEL. As a result, a signal indicating a level of the charge accumulated in the FD  55  is output to the column signal processing circuit  35  from the amplification transistor  57  via the selection transistor  58 . 
     As described above, the pixel  32  including the pixel circuit of  FIG. 5  is capable of performing operation (imaging) of a global shutter system which sets the same exposure time for all the pixels of the pixel array unit  33 , temporarily retains charges in the memory units  53  after an exposure end, and sequentially reads the charges from the memory units  53  in units of row. 
     Note that the circuit configuration of each of the pixels  32  is not limited to the configuration depicted in  FIG. 5 , but may be a circuit configuration which does not have the memory unit  53  and performs operation of what is generally called a rolling shutter system, for example. 
     &lt;Basic Structure Example of Solid-State Imaging Device&gt; 
     A detailed structure of the solid-state imaging element  11  will be subsequently described with reference to  FIG. 6 .  FIG. 6  is a cross-sectional diagram depicting an enlarged part of the solid-state imaging element  11 . 
     For example, the logic substrate  11   a  includes a multilayer wiring layer  82  which is provided on the upper side (pixel sensor substrate  11   b  side) of a semiconductor substrate  81  constituted by a silicon (Si) (hereinafter referred to as silicon substrate  81 ), for example. The multilayer wiring layer  82  constitutes the control circuit  22  and the logic circuit  23  of  FIG. 3 . 
     The multilayer wiring layer  82  includes a plurality of wiring layers  83  constituted by a wiring layer  83   a  in an uppermost layer closest to the pixel sensor substrate  11   b , a wiring layer  83   b  in a middle part, a wiring layer  83   c  in a lowermost layer closest to the silicon substrate  81 , and others, and includes an interlayer dielectric  84  formed between the respective wiring layers  83 . 
     The plurality of wiring layers  83  is made of copper (Cu), aluminum (Al), tungsten (W), or the like, for example, while the interlayer dielectric  84  is made of silicon oxide, silicon nitride, or the like, for example. Each of the plurality of wiring layers  83  and the interlayer dielectric  84  may be made of the same material for all the layers, or may be made of two or more materials different for each layer. 
     A silicon through hole  85  penetrating the silicon substrate  81  is formed at a predetermined position of the silicon substrate  81 . A connection conductor  87  is embedded in an inner wall of the silicon through hole  85  via an insulation film  86  to form a silicon through electrode (TSV: Through Silicon Via)  88 . For example, the insulation film  86  may be constituted by an SiO2 film, an SiN film or the like. 
     Note that the through electrode  88  depicted in  FIG. 6  is configured such that the insulation film  86  and the connection conductor  87  are formed along the inner wall surface, and that the inside of the silicon through hole  85  is hollow. However, the inside of the silicon through hole  85  may be entirely embedded with the connection conductor  87  depending on the inner diameter of the through electrode  88 . In other words, either the configuration where the inside of the through hole is embedded with conductor, or the configuration where a part of the through hole is hollow may be adopted. This is also applicable to a chip through electrode (TCV: Through Chip Via)  105  and others described below. 
     The connection conductor  87  of the silicon through electrode  88  is connected to rewiring  90  formed on the lower surface side of the silicon substrate  81 . The rewiring  90  is connected to the solder ball  11   e . For example, each of the connection conductor  87  and the rewiring  90  may be made of copper (Cu), tungsten (W), polysilicon, or the like. 
     In addition, a solder mask (solder resist)  91  is provided in such a manner as to cover the rewiring  90  and the insulation film  86  on the lower surface side of the silicon substrate  81  except for a region where the solder ball  11   e  is formed. 
     On the other hand, the pixel sensor substrate  11   b  includes a multilayer wiring layer  102  provided on the lower side (logic substrate  11   a  side) of a semiconductor substrate  101  made of silicon (Si) (hereinafter referred to as silicon substrate  101 ). The multilayer wiring layer  102  constitutes the pixel circuit of the pixel region  21  of  FIG. 3 . 
     The multilayer wiring layer  102  includes a plurality of wiring layers  103  constituted by a wiring layer  103   a  in an uppermost layer closest to the silicon substrate  101 , a wiring layer  103   b  in a middle part, a wiring layer  103   c  in a lowermost layer closest to the logic substrate  11   a , and others, and includes an interlayer dielectric  104  formed between the respective wiring layers  103 . 
     Materials forming the plurality of wiring layers  103  and the interlayer dielectric  104  may be the same types of materials forming the wiring layers  83  and the interlayer dielectric  84  described above. In addition, similarly to the wiring layers  83  and the interlayer dielectric  84  described above, each of the plurality of wiring layers  103  and the interlayer dielectric  104  may be made of one material, or two or more materials different for each layer. 
     According to the example of  FIG. 6 , the multilayer wiring layer  102  of the pixel sensor substrate  11   b  is constituted by the three wiring layers  103 , while the multilayer wiring layer  82  of the logic substrate  11   a  is constituted by the four wiring layers  83 . However, note that the total numbers of the wiring layers are not limited to these numbers but may be any numbers of layers. 
     The photodiode  51  formed by pn junction is provided for each of the pixels  32  within the silicon substrate  101 . 
     In addition, while not depicted in the figure, a plurality of pixel transistors such as the first transfer transistor  52  and the second transfer transistor  54 , the memory unit (MEM)  53 , and others are also included in the multilayer wiring layer  102  and the silicon substrate  101 . 
     A silicon through electrode  109  connected to the wiring layer  103   a  of the pixel sensor substrate  11   b , and a chip through electrode  105  connected to the wiring layer  83   a  of the logic substrate  11   a  are provided at predetermined positions of the silicon substrate  101  in a portion where the color filters  11   c  and the on-chip lenses  11   d  are not provided. 
     The chip through electrode  105  and the silicon through electrode  109  are connected by connection wiring  106  provided on an upper surface of the silicon substrate  101 . In addition, an insulation film  107  is provided between the silicon substrate  101  and each of the silicon through electrode  109  and the chip through electrode  105 . The color filters  11   c  and the on-chip lenses  11   d  are further provided on the upper surface of the silicon substrate  101  via a flattening film (insulation film)  108 . 
     As described above, the solid-state imaging element  11  depicted in  FIG. 2  has a laminated structure produced by affixing the multilayer wiring layer  102  side of the logic substrate  11   a  and the multilayer wiring layer  82  side of the pixel sensor substrate  11   b . In  FIG. 6 , an affixing plane of the multilayer wiring layer  102  side of the logic substrate  11   a  and the multilayer wiring layer  82  side of the pixel sensor substrate  11   b  is indicated by a broken line. 
     In addition, according to the solid-state imaging element  11  of the imaging device  1 , the wiring layer  103  of the pixel sensor substrate  11   b  and the wiring layer  83  of the logic substrate  11   a  are connected by two through electrodes constituted by the silicon through electrode  109  and the chip through electrode  105 , while the wiring layer  83  of the logic substrate  11   a  and the solder ball (back electrode)  11   e  are connected by the silicon through electrode  88  and the rewiring  90 . In this manner, a plane area of the imaging device  1  can be reduced to a minimum. 
     Moreover, the solid-state imaging element  11  and the glass substrate  12  are affixed by a non-cavity structure using the adhesive  13  to reduce a length in a height direction. 
     Accordingly, the imaging device  1  depicted in  FIG. 1  is capable of actualizing a more miniaturized semiconductor device (semiconductor package). 
     According to the configuration of the imaging device  1  described above, the IRCF  14  is provided above the solid-state imaging element  11  and the glass substrate  12 . Accordingly, generation of a flare and a ghost caused by internal diffused reflection of light can be reduced. 
     Specifically, in a case where the IRCF  14  is provided in the vicinity of an intermediate position between the lens (Lens)  16  and the glass substrate (Glass)  12  away from the glass substrate  12  as depicted in a left part of  FIG. 7 , incident light is converged as indicated by a solid line, enters the solid-state imaging element  11  (CIS) at a position F 0  via the IRCF  14 , the glass substrate  12 , and the adhesive  13 , and then is reflected at the position F 0  as indicated by dotted lines to be produced as reflection light. 
     As indicated by dotted lines, for example, a part of the reflection light reflected at the position F 0  is reflected on a rear surface R 1  of the IRCF  14  (lower surface in  FIG. 7 ) disposed at a position away from the glass substrate  12  via the adhesive  13  and the glass substrate  12 , and again enters the solid-state imaging element  11  at a position F 1  again via the glass substrate  12  and the adhesive  13 . 
     In addition, as indicated by dotted lines, for example, another part of the reflection light reflected at the focus F 0  passes through the adhesive  13 , the glass substrate  12 , and the IRCF  14  disposed at a position away from the glass substrate  12 , and is reflected on an upper surface R 2  of the IRCF  14  (upper surface in  FIG. 7 ), and again enters the solid-state imaging element  11  at a position F 2  via the IRCF  14 , the glass substrate  12 , and the adhesive  13 . 
     The lights again entering at the positions F 1  and F 2  produce a flare or a ghost caused by internal diffused reflection. More specifically, as depicted in an image P 1  of  FIG. 8 , a flare or a ghost appears as indicated by reflection lights R 21  and R 22  during imaging an illumination L by the solid-state imaging element  11 . 
     On the other hand, when the IRCF  14  is provided on the glass substrate  12  as that in the imaging device  1  depicted in a right part of  FIG. 7  and corresponding to the configuration of the imaging device  1  of  FIG. 1 , incident light indicated by solid lines is converged, enters the solid-state imaging element  11  at a position F 0  via the IRCF  14 , the adhesive  15 , the glass substrate  12 , and the adhesive  13 , and then is reflected as indicated by dotted lines. Thereafter, the reflected light is reflected on a lens surface R 11  in the lowermost layer on the lens group  16  via the adhesive  13 , the glass substrate  12 , the adhesive  15 , and the IRCF  14 . However, in a state where the lens group  16  is located sufficiently away from the IRCF  14 , this light is reflected in such a range as not to be sufficiently received by the solid-state imaging element  11 . 
     The solid-state imaging element  11 , the glass substrate  12 , and the IRCF  14  surrounded by a one-dot chain line in the figure here are affixed to each other by the adhesives  13  and  15  having substantially the same refractive index to constitute the integrated configuration unit  10  as an integrated configuration. According to the integrated configuration unit  10 , internal diffused reflection caused at a boundary between layers having different refractive indexes is reduced by equalizing refractive indexes to reduce reentrance of light at the positions F 1  and F 2  located close to the position F 0  in the left part of  FIG. 7 , for example. 
     In this manner, for imaging the illumination L, the imaging device  1  of  FIG. 1  is capable of capturing an image where a flare or a ghost caused by internal diffused reflection, such as the reflection lights R 21  and R 22  in the image P 1 , is reduced as indicated by an image P 2  of  FIG. 8 . 
     As a result, reduction of a flare of a ghost caused by internal diffused reflection can be achieved as well as miniaturization and height reduction of the device configuration by the configuration of the imaging device  1  in the first embodiment depicted in  FIG. 1 . 
     Note that the image P 1  of  FIG. 8  is a captured image of the illumination L at night by using the imaging device  1  having the configuration in the left part of  FIG. 7 , while the image P 2  is a captured image of the illumination L at night by the imaging device  1  (of  FIG. 1 ) having the configuration in the right part of  FIG. 7 . 
     In addition, while the example described above is the configuration which achieves auto-focusing by adjusting a focal distance according to a distance to an object by moving the lens group  16  in the up-down direction in  FIG. 1  using the actuator  18 , a function of what is generally called a single focus lens may be performed while eliminating the actuator  18  and adjustment of the focal distance by the lens group  16 . 
     2. Second Embodiment 
     According to the example presented in the first embodiment described above, the IRCF  14  is affixed onto the glass substrate  12  affixed to the imaging surface side of the solid-state imaging element  11 . In this case, the lens in the lowermost layer constituting the lens group  16  may be further provided on the IRCF  14 . 
       FIG. 9  depicts a configuration example of the imaging device  1  which separates, from the lens group  16 , the lens in the lowermost layer with respect to a light incident direction in the lens group  16  constituted by a plurality of lenses forming the imaging device  1  of  FIG. 1 , and provides the separated lens on the IRCF  14 . Note that configurations depicted in  FIG. 5  and having functions basically identical to the functions of the configurations of  FIG. 1  are given identical reference signs. Description of those configurations will be omitted where appropriate. 
     Specifically, the imaging device  1  of  FIG. 9  is different from the imaging device  1  of  FIG. 1  in that a lens  131  in the lowermost layer with respect to a light incident direction in the plurality of lenses constituting the lens group  16  is further separated from the lens group  16  and provided on the upper surface of the IRCF  14  in the figure. Note that the lens group  16  of  FIG. 9  is given a reference sign identical to the reference sign of the lens group  16  of  FIG. 1 , but is different from the lens group  16  of  FIG. 1  in a strict sense in a point that the lens  131  located in the lowermost layer with respect to the light incident direction is not included. 
     According to the configuration of the imaging device  1  as depicted in  FIG. 9 , the IRCF  14  is provided on the glass substrate  12  formed on the solid-state imaging element  11 . Further, the lens  131  in the lowermost layer constituting the lens group  16  is provided on the IRCF  14 . Accordingly, generation of a flare and a ghost caused by internal diffused reflection of light can be reduced. 
     Specifically, in a case where the lens  131  in the lowermost layer of the lens group  16  with respect to the light incident direction is provided on the glass substrate  12  in a state where the IRCF  14  is provided in the vicinity of an intermediate position between the lens group  16  and the lens  131  and away from the lens  131  as depicted in a left part of  FIG. 10 , incident light indicated by solid lines is converged, enters the solid-state imaging element  11  at the position F 0  via the IRCF  14 , the lens  131 , the glass substrate  12 , and the adhesive  13 , and then is reflected from the position F 0  as indicated by dotted lines to be produced as reflection light. 
     As indicated by dotted lines, for example, a part of the reflection light reflected at the position F 0  is reflected on a rear surface R 31  of the IRCF  14  (lower surface in  FIG. 2 ) disposed at a position away from the lens  131  via the adhesive  13 , the glass substrate  12 , and the lens  131 , and again enters the solid-state imaging element  11  at a position F 11  via the lens  131 , the glass substrate  12 , and the adhesive  13 . 
     In addition, as indicated by dotted lines, for example, another part of the reflection light reflected at the focus F 0  passes through the adhesive  13 , the glass substrate  12 , the lens  131 , and the IRCF  14  disposed at a position away from the lens  131 , and is reflected on an upper surface R 32  of the IRCF  14  (upper surface in  FIG. 7 ), and again enters the solid-state imaging element  11  at a position F 12  via the IRCF  14 , the lens  131 , the glass substrate  12 , and the adhesive  13 . 
     The light again entering at the positions F 11  and F 12  appears as a flare or a ghost in the solid-state imaging element  11 . A principle applicable to this point is basically similar to the principle of the case where the reflection lights R 21  and R 21  of the illumination L in the image P 1  described with reference to  FIG. 8  reenter at the positions F 1  and F 2  of  FIG. 7 . 
     On the other hand, similarly to the configuration of the imaging device  1  of  FIG. 9 , when the lens  131  in the lowermost layer of the lens group  16  is provided on the IRCF  14  as depicted in a right part of  FIG. 10 , incident light is converged and enters the solid-state imaging element  11  at the position F 0  via the lens  131 , the IRCF  14 , the adhesive  15 , the glass substrate  12 , and the adhesive  13  as indicated by solid lines, and then is reflected and produced as reflection light reflected on a surface R 41  on the lens group  16  at a position sufficiently away via the adhesive  13 , the glass substrate  12 , the adhesive  15 , the IRCF  14 , and the lens  131  as indicated by dotted lines. In this case, the reflection light is reflected in a range substantially unreceivable by the solid-state imaging element  11 . Accordingly, generation of a flare or a ghost can be reduced. 
     Specifically, the solid-state imaging element  11 , the adhesive  13 , the glass substrate  12 , and the IRCF  14  are affixed to each other by the adhesives  13  and  15  having substantially the same refractive index to constitute an integrated configuration. In this case, the refractive index of the integrated configuration unit  10  as an integrated configuration surrounded by a one-dot chain line in the figure is equalized. Accordingly, internal diffused reflection caused at a boundary of layers having different refractive indexes is reduced, and entrance of reflection light to the positions F 11  and F 12  close to the position F 0  is reduced as depicted in a left part of  FIG. 10 , for example. 
     As a result, reduction of a flare of a ghost caused by internal diffused reflection can be achieved as well as miniaturization and height reduction of the device configuration by the configuration of the imaging device  1  in the second embodiment depicted in  FIG. 10 . 
     3. Third Embodiment 
     According to the example presented in the second embodiment described above, the lens  131  in the lowermost layer is provided on the IRCF  14 . In this case, the lens  131  in the lowermost layer and the IRCF  14  may be affixed to each other by an adhesive. 
       FIG. 11  depicts a configuration example of the imaging device  1  where the lens  131  in the lowermost layer and the IRCF  14  are affixed to each other by an adhesive. Note that configurations included in the imaging device  1  of  FIG. 11  and having functions basically identical to the functions of the configurations of the imaging device  1  of  FIG. 9  are given identical reference signs. Description of those configurations will be omitted where appropriate. 
     Specifically, the imaging device  1  of  FIG. 11  is different from the imaging device  1  of  FIG. 9  in that the lens  131  in the lowermost layer and the IRCF  14  are affixed to each other by an adhesive  151  which is transparent, i.e., has substantially the same refractive index. 
     According to the configuration of the imaging device  1  of  FIG. 11 , generation of a flare and a ghost can be reduced similarly to the imaging device  1  of  FIG. 9 . 
     Moreover, in a case where the lens  131  does not have high flatness, the IRCF  14  may deviate from an optical axis of the lens  131  when fixation to the IRCF  14  without using the adhesive  151  is attempted. However, by affixing the lens  131  and the IRCF  14  to each other by the adhesive  151 , the IRCF  14  can be fixed without deviation from the optical axis of the lens  131  even when the lens  131  does not have high flatness. Accordingly, reduction of distortion of an image generated by deviation of the optical axis is achievable. 
     4. Fourth Embodiment 
     According to the example presented in the second embodiment described above, the lens  131  in the lowermost layer with respect to the light incident direction is provided on the IRCF  14 . However, not only the lens  131  in the lowermost layer but also a plurality of lenses constituting the lowermost layer of the lens group  16  may be provided on the IRCF  14 . 
       FIG. 12  depicts a configuration example of the imaging device  1  which includes a lens group included in the lens group  16  and constituted by a plurality of lenses forming the lowermost layer with respect to the incident direction, as a lens group disposed on the IRCF  14 . Note that configurations included in the imaging device  1  of  FIG. 12  and having functions basically identical to the functions of the configurations of the imaging device  1  of  FIG. 9  are given identical reference signs. Description of those configurations will be omitted where appropriate. 
     Specifically, the imaging device  1  of  FIG. 12  is different from the imaging device  1  of  FIG. 9  in that, instead of the lens  131 , a lens group  171  included in the lens group  16  and constituted by a plurality of lenses forming the lowermost layer with respect to the light incident direction is provided on the IRCF  14 . Note that, while  FIG. 12  depicts an example of the lens group  171  constituted by two lenses, the lens group  171  may be constituted by a larger number of lenses. 
     According to such a configuration, generation of a flare and a ghost can be reduced similarly to the imaging device  1  of  FIG. 9 . 
     Moreover, the lens group  171  which is included in the plurality of lenses constituting the lens group  16  and forms the lowermost layer is provided on the IRCF  14 . In this case, the number of lenses constituting the lens group  16  is allowed to decrease, and the lens group  16  thus becomes lightweight. Accordingly, a driving amount used by the actuator  18  for auto-focusing is allowed to decrease, and therefore miniaturization and power reduction of the actuator  18  are achievable. 
     Note that the lens  131  included in the imaging device  1  of  FIG. 11  in the third embodiment may be affixed to the IRCF  14  by using the adhesive  151  which is transparent, instead of the lens group  171 . 
     5. Fifth Embodiment 
     According to the example presented in the second embodiment described above, the glass substrate  12  is affixed onto the solid-state imaging element  11  via the adhesive  13 , while the IRCF  14  is affixed onto the glass substrate  12  via the adhesive  15 . However, each of the glass substrate  12 , the adhesive  15 , and the IRCF  14  may be replaced with a configuration having both the function of the glass substrate  12  and the function of the IRCF  14 , and affixed onto the solid-state imaging element  11  via the adhesive  13 . 
       FIG. 13  depicts a configuration example of the imaging device  1  in which the glass substrate  12 , the adhesive  15 , and the IRCF  14  are replaced with a configuration having both the function of the glass substrate  12  and the function of the IRCF  14 , and affixed onto the solid-state imaging element  11  via the adhesive  13 . The lens  131  in the lowermost layer is provided on this configuration. Note that configurations included in the imaging device  1  of  FIG. 13  and having functions basically identical to the functions of the configurations of the imaging device  1  of  FIG. 9  are given identical reference signs. Description of those configurations will be omitted where appropriate. 
     Specifically, the imaging device  1  of  FIG. 13  is different from the imaging device  1  of  FIG. 9  in that the glass substrate  12  and the IRCF  14  are replaced with an IRCF glass substrate  14 ′ having the function of the glass substrate  12  and the function of the IRCF  14 . The IRCF glass substrate  14 ′ is affixed onto the solid-state imaging element  11  via the adhesive  13 , and the lens  131  in the lowermost layer is provided on the IRCF  14 ′. 
     According to such a configuration, generation of a flare and a ghost can be reduced similarly to the imaging device  1  of  FIG. 9 . 
     Specifically, at present, for miniaturization of the solid-state imaging element  11 , the glass substrate  12  called a CSP (Chip Size Package) structure and the solid-state imaging element  11  are bonded to each other, and the solid-state imaging element  11  is thinned with the glass substrate designated as a basic substrate. In this manner, a miniaturized solid-state imaging element is realizable. In  FIG. 13 , the IRCF glass substrate  14 ′ performs the function of the glass substrate  12  having high flatness as well as the function of the IRCF  14 . Accordingly, height reduction is achievable. 
     Note that the glass substrate  12 , the adhesive  15 , and the IRCF  14  included in the imaging device  1  of  FIGS. 1, 11, and 12  in the first embodiment, the third embodiment, and the fourth embodiment may be replaced with the IRCF glass substrate  14 ′ having both the function of the glass substrate  12  and the function of the IRCF  14 . 
     6. Sixth Embodiment 
     According to the example presented in the fourth embodiment described above, the glass substrate  12  is affixed onto the solid-state imaging element  11  having the CSP structure via the adhesive  13 . In addition, the IRCF  14  is affixed onto the glass substrate  12  via the adhesive  15 , and also the lens group  171  constituted by the plurality of lenses in the lowermost layer in the plurality of lenses constituting the lens group  16  is provided on the IRCF  14 . However, the solid-state imaging element  11  having a COB (Chip on Board) structure may be used instead of the solid-state imaging element  11  having the CSP structure. 
     According to a configuration example depicted in  FIG. 14 , the glass substrate  12  and the IRCF  14  included in the imaging device  1  of  FIG. 12  are replaced with the IRCF glass substrate  14 ′ having the function of the glass substrate  12  and the function of the IRCF  14 , and the solid-state imaging element  11  having the COB (Chip on Board) structure is used instead of the solid-state imaging element  11  having the CSP structure. Note that configurations included in the imaging device  1  of FIG.  14  and having functions basically identical to the functions of the configurations of the imaging device  1  of  FIG. 12  are given identical reference signs. Description of those configurations will be omitted where appropriate. 
     Specifically, the imaging device  1  of  FIG. 14  is different from the imaging device  1  of  FIG. 12  in that the glass substrate  12  and the IRCF  14  are replaced with the IRCF glass substrate  14 ′ having the function of the glass substrate  12  and the function of the IRCF  14 , and that a solid-state imaging element  91  having the COB (Chip on Board) structure is used instead of the solid-state imaging element  11  having the CSP structure. 
     According to such a configuration, generation of a flare and a ghost can be reduced similarly to the imaging device  1  of  FIG. 12 . 
     Moreover, in recent years, the CSP structure has been generally adopted for miniaturization of the solid-state imaging element  11  and miniaturization of the imaging device  1 . However, the CSP structure requires complicated processing, such as affixation with the glass substrate  12  or the IRCF glass substrate  14 ′, and wiring of terminals of the solid-state imaging element  11  on the back side of the light receiving surface. Accordingly, the CSP structure is more expensive than the solid-state imaging element  11  having the COB structure. Accordingly, the solid-state imaging element  91  having the COB structure and connected with the circuit board  17  via a wire bond  92  or the like may be used as well as the CSP structure. 
     Connection to the circuit board  17  is facilitated by using the solid-state imaging element  91  having the COB structure. Accordingly, simplification of processing and cost reduction are achievable. 
     Note that the solid-state imaging element  11  having the CSP structure and included in the imaging device  1  of  FIGS. 1, 9, 11, and 13  in the first to third embodiments and the fifth embodiment may be replaced with the solid-state imaging element  11  having the COB (Chip on Board) structure. 
     7. Seventh Embodiment 
     According to the example presented in the second embodiment described above, the glass substrate  12  is provided on the solid-state imaging element  11 , and the IRCF  14  is further provided on the glass substrate. However, the IRCF  14  may be provided on the solid-state imaging element  11 , and the glass substrate  12  may be further provided on the IRCF  14 . 
       FIG. 15  is a configuration example of the imaging device  1  in a case where the glass substrate  12  is provided. In this case, the IRCF  14  is provided on the solid-state imaging element  11 , and the glass substrate  12  is further provided on the IRCF  14 . 
     The imaging device  1  of  FIG. 15  is different from the imaging device  1  of  FIG. 9  in that the order of the glass substrate  12  and the IRCF  14  is changed. In this case, the IRCF  14  is affixed onto the solid-state imaging element  11  via the adhesive  13  which is transparent, the glass substrate  12  is further affixed onto the IRCF  14  via the adhesive  15  which is transparent, and the lens  131  is provided on the glass substrate  12 . 
     According to such a configuration, generation of a flare and a ghost can be reduced similarly to the imaging device  1  of  FIG. 9 . 
     In addition, according to the characteristics of the IRCF  14 , flatness of the IRCF  14  is generally lowered by an effect of a temperature and a disturbance. In this case, distortion may be produced in an image on the solid-state imaging element  11 . 
     Accordingly, a special material for maintaining flatness is generally adopted, such as a material of coating applied on both surfaces of the IRCF  14 , for example. However, this material raises costs. 
     On the other hand, according to the imaging device  1  of  FIG. 15 , the IRCF  14  having low flatness is sandwiched between the solid-state imaging element  11  and the glass substrate  12  both having high flatness. In this manner, flatness can be secured at low costs, and therefore distortion of an image can be reduced. 
     Accordingly, the imaging device  1  of  FIG. 15  achieves reduction of a flare or a ghost, and also reduction of distortion in an image produced by the characteristics of the IRCF  14 . Further, the necessity of coating made of a special material for maintaining flatness is eliminated, and therefore cost reduction is achievable. 
     Note that the glass substrate  12  and the IRCF  14  may be also affixed to each other via the adhesives  13  and  15  in the state of the change of the order of the glass substrate  12  and the IRCF  14  in the imaging device  1  of  FIGS. 1, 11, and 12  in the first embodiment, the third embodiment, and the fourth embodiment. 
     8. Eighth Embodiment 
     According to the example presented in the first embodiment described above, the IRCF  14  is used as a configuration for cutting off infrared light. However, configurations other than the IRCF  14  may be adopted as long as cut-off of infrared light is achievable. For example, infrared cut resin may be applied and used instead of the IRCF  14 . 
       FIG. 16  depicts a configuration example of the imaging device  1  using infrared cut resin instead of the IRCF  14 . Note that configurations included in the imaging device  1  of  FIG. 16  and having functions basically identical to the functions of the configurations of the imaging device  1  of  FIG. 1  are given identical reference signs. Description of those configurations will be omitted where appropriate. 
     Specifically, the imaging device  1  of  FIG. 16  is different from the imaging device  1  of  FIG. 1  in that an infrared cut resin  211  is provided instead of the IRCF  14 . For example, the infrared cut resin  211  is provided by coating. 
     According to such a configuration, generation of a flare and a ghost can be reduced similarly to the imaging device  1  of  FIG. 1 . 
     Moreover, resin with infrared cut effect is generally adopted with recent improvement of resin. It is known that the glass substrate  12  can be coated with the infrared cut resin  211  during production of the CSP type solid-state imaging element  11 . 
     Note that the infrared cut resin  211  may be adopted instead of the IRCF  14  included in the imaging device  1  of  FIGS. 9, 11, 12, and 15  in the second to fourth embodiments and the seventh embodiment. 
     9. Ninth Embodiment 
     According to the example presented in the second embodiment described above, the glass substrate  12  having a flat plate shape is provided in a state of close contact with the solid-state imaging element  11  without cavities in a case of use of the glass substrate  12 . However, cavities may be provided between the glass substrate  12  and the solid-state imaging element  11 . 
       FIG. 17  is a configuration example of the imaging device  1  which includes cavities between the glass substrate  12  and the solid-state imaging element  11 . Note that configurations included in the imaging device  1  of  FIG. 17  and having functions basically identical to the functions of the configurations of the imaging device  1  of  FIG. 9  are given identical reference signs. Description of those configurations will be omitted where appropriate. 
     Specifically, the imaging device  1  of  FIG. 17  is different from the imaging device  1  of  FIG. 9  in that a glass substrate  231  including protrusions  231   a  in a periphery is provided instead of the glass substrate  12 . The protrusions  231   a  in the periphery are brought into contact with the solid-state imaging element  11 , and bonded by an adhesive  232  which is transparent. In this manner, cavities  231   b  each constituted by an air layer are formed between the imaging surface of the solid-state imaging element  11  and the glass substrate  231 . 
     According to such a configuration, generation of a flare and a ghost can be reduced similarly to the imaging device  1  of  FIG. 9 . 
     Note that the glass substrate  231  may be used instead of the glass substrate  12  included in the imaging device  1  of  FIGS. 1, 11, 12, and 16  in the first embodiment, the third embodiment, the fourth embodiment, and the eighth embodiment to form the cavities  231   b  by bonding only the protrusions  231   a  via the adhesive  232 . 
     10. Tenth Embodiment 
     According to the example presented in the second embodiment described above, the lens  131  in the lowermost layer in the lens group  16  is provided on the IRCF  14  formed on the glass substrate  12 . However, a coating agent constituted by an organic multilayer film and having an infrared cut function may be used instead of the IRCF  14  on the glass substrate  12 . 
       FIG. 18  depicts a configuration example of the imaging device  1  which includes a coating agent constituted by an organic multilayer film and having an infrared cut function instead of the IRCF  14  on the glass substrate  12 . 
     The imaging device  1  of  FIG. 18  is different from the imaging device  1  of  FIG. 9  in that the coating agent  251  constituted by the organic multilayer film and having the infrared cut function is provided instead of the IRCF  14  on the glass substrate  12 . 
     According to such a configuration, generation of a flare and a ghost can be reduced similarly to the imaging device  1  of  FIG. 9 . 
     Note that the coating agent  251  constituted by the organic multilayer film and having the infrared cut function may be adopted instead of the IRCF  14  included in the imaging device  1  of  FIGS. 1, 6, 7, 10, and 12  in the first embodiment, the third embodiment, the fourth embodiment, the seventh embodiment, and the ninth embodiment. 
     11. Eleventh Embodiment 
     According to the example presented in the tenth embodiment described above, the lens  131  in the lowermost layer in the lens group  16  is provided on the coating agent  251  constituted by the organic multilayer film and having the infrared cut function instead of the IRCF  14  on the glass substrate  12 . In this case, the lens  131  may be further coated with an AR (Anti Reflection) coating. 
       FIG. 19  is a configuration example of the imaging device  1  which includes the lens  131  coated with an AR coating in the imaging device  1  of  FIG. 13 . 
     Specifically, the imaging device  1  of  FIG. 19  is different from the imaging device  1  of  FIG. 18  in that a lens  271  included in the lowermost layer of the lens group  16  and coated with an AR coating  271   a  is provided instead of the lens  131 . For example, vacuum deposition, sputtering, WET coating, or the like may be adopted for the AR coating  271   a.    
     According to such a configuration, generation of a flare and a ghost can be reduced similarly to the imaging device  1  of  FIG. 9 . 
     Further, the AR coating  271   a  of the lens  271  reduces internal diffused reflection of reflection light from the solid-state imaging element  11 . Accordingly, reduction of generation of a flare or a ghost is achievable with higher accuracy. 
     Note that the lens  271  coated with the AR coating  271   a  may be adopted instead of the lens  131  included in the imaging device  1  of  FIGS. 9, 11, 13, 15, 17 , and  18  in the second embodiment, the third embodiment, the fifth embodiment, the seventh embodiment, the ninth embodiment, and the tenth embodiment. In addition, a surface of the lens group  171  (the uppermost surface in the figure) included in the imaging device  1  of  FIGS. 12 and 14  in the fourth embodiment and the sixth embodiment may be coated with an AR coating similar to the AR coating  271   a.    
     It is preferable that the AR coating  271   a  is a single-layered or multi-layered structure film constituted as follows. Specifically, for example, the AR coating  271   a  is a transparent resin such as silicon resin, acrylic resin, epoxy resin, and styrene resin, an insulation film (e.g., SiCH, SiCOH, and SiCNH) chiefly containing Si (silicon), C (carbon), and H (hydrogen), an insulation film (e.g., SiON and SiN) chiefly containing Si (silicon) and N (nitrogen), or an SiO2 film, a P—SiO film, or HDP-SiO film formed using an oxidant and an material gas which is at least any one of silicon hydroxide, alkylsilane, alkoxysilane, polysiloxane, or the like. 
     12. Twentieth Embodiment 
     According to the example presented in the eleventh embodiment described above, the lens  271  coated with the AR (Anti Reflection) coating  271   a  is used instead of the lens  131 . However, a configuration other than AR coating may be used as long as an anti-reflection function can be performed. For example, a moth eye structure including minute recesses and protrusions for preventing reflection may be adopted. 
       FIG. 20  is a configuration example of the imaging device  1  which includes a lens  291  to which an anti-reflection function having a moth eye structure is added instead of the lens  131  included in the imaging device  1  of  FIG. 19 . 
     Specifically, the imaging device  1  of  FIG. 20  is different from the imaging device  1  of  FIG. 18  in that the lens  291  in the lowermost layer of the lens group  16  is provided instead of the lens  131 . The lens  291  includes an anti-reflection treatment portion  291   a  subjected to a moth eye structure treatment. 
     According to such a configuration, generation of a flare and a ghost can be reduced similarly to the imaging device  1  of  FIG. 18 . 
     Moreover, the anti-reflection treatment portion  291   a  included in the lens  291  and subjected to the moth eye structure treatment reduces internal diffused reflection of reflection light from the solid-state imaging element  11 . Accordingly, reduction of generation of a flare or a ghost is achievable with higher accuracy. Note that the anti-reflection treatment portion  291   a  may be subjected to anti-reflection treatments other than the moth eye structure as long as the anti-reflection function can be achieved. 
     It is preferable that the anti-reflection treatment portion  291   a  is a single-layered or multi-layered structure film constituted as follows. Specifically, for example, the anti-reflection treatment portion  291   a  is a transparent resin such as silicon resin, acrylic resin, epoxy resin, and styrene resin, an insulation film (e.g., SiCH, SiCOH, and SiCNH) chiefly containing Si (silicon), C (carbon), and H (hydrogen), an insulation film (e.g., SiON and SiN) chiefly containing Si (silicon) and N (nitrogen), or an SiO2 film, a P—SiO film, or HDP-SiO film formed using an oxidant and an material gas which is at least any one of silicon hydroxide, alkylsilane, alkoxysilane, polysiloxane, or the like. 
     Note that the lens  291  to which the anti-reflection treatment portion  291   a  is added may be adopted instead of the lens  131  included in the imaging device  1  of  FIGS. 9, 11, 13, 15, 17, and 18  in the second embodiment, the third embodiment, the fifth embodiment, the seventh embodiment, the ninth embodiment, and the tenth embodiment. In addition, the surface of the lens group  171  included in the imaging device  1  of  FIGS. 12 and 14  in the fourth embodiment and the sixth embodiment may be subjected to anti-reflection treatment similar to the treatment of the anti-reflection treatment portion  291   a.    
     13. Thirteenth Embodiment 
     According to the example presented in the fourth embodiment described above, the lens  131  in the lowermost layer of the lens group  16  is provided on the IRCF  14 . However, this configuration may be replaced with a configuration having an infrared cut function, and a function similar to the function of the lens  131  in the lowermost layer. 
       FIG. 21  depicts a configuration example of the imaging device  1  which includes an infrared cut lens having an infrared cut function, and a function similar to the function of the lens in the lowermost layer of the lens group  16 , instead of the IRCF  14  and the lens  131  in the lowermost layer of the lens group  16  included in the imaging device  1  of  FIG. 9 . 
     Specifically, the imaging device  1  of  FIG. 21  is different from the imaging device  1  of  FIG. 9  in that an infrared cut lens  301  having an infrared cut function is provided instead of the IRCF  14  and the lens  131  in the lowermost layer of the lens group  16 . 
     According to such a configuration, generation of a flare and a ghost can be reduced similarly to the imaging device  1  of  FIG. 9 . 
     Moreover, the infrared cut lens  301  is configured to have both the infrared cut function and the function of the lens  131  in the lowermost layer of the lens group  16 . In this case, the necessity of separately providing the IRCF  14  and the lens  131  is eliminated. Accordingly, further miniaturization and height reduction of the device configuration of the imaging device  1  are achievable. Furthermore, the lens group  171  and the IRCF  14  included in the imaging device  1  of  FIG. 12  in the fourth embodiment may be replaced with an infrared cut lens having both the infrared cut function and the function of the lens group  171  constituted by a plurality of lenses in the lowermost layer of the lens group  16 . 
     14. Fourteenth Embodiment 
     It is known that stray light easily enters from a peripheral edge portion of the light receiving surface of the solid-state imaging element  11 . Accordingly, a black mask may be provided in the peripheral edge portion of the light receiving surface of the solid-state imaging element  11  to reduce entrance of stray light and thereby reduce generation of a flare or a ghost. 
     A left part of  FIG. 22  depicts a configuration example of the imaging device  1  which includes a glass substrate  321  equipped with a black mask  321   a  for light shield of the peripheral edge portion of the light receiving surface of the solid-state imaging element  11 , instead of the glass substrate  12  included in the imaging device  1  of  FIG. 18 . 
     Specifically, the imaging device  1  in the left part of  FIG. 22  is different from the imaging device  1  of  FIG. 18  in that, instead of the glass substrate  12 , the glass substrate  321  equipped with the black mask  321   a  constituted by a light shielding film is provided at a peripheral edge portion Z 2  as indicated in a right part of  FIG. 22 . The black mask  321   a  is formed on the glass substrate  321  by photolithography or the like. Note that the black mask is not provided at a central portion Z 1  of the glass substrate  321  in the right part of  FIG. 22 . 
     According to such a configuration, generation of a flare and a ghost can be reduced similarly to the imaging device  1  of  FIG. 9 . 
     In addition, the glass substrate  321  equipped with the black mask  321   a  in the peripheral edge portion Z 2  can reduce entrance of stray light from the peripheral edge portion, thereby reducing generation of a flare or a ghost caused by stray light. 
     Note that the black mask  321   a  may be provided not only on the glass substrate  321  but also on configurations other than the glass substrate  321  as long as entrance of stray light into the solid-state imaging element  11  can be prevented. For example, the black mask  321   a  may be provided on the coating agent  251  constituted by the organic multilayer film and having the infrared light cut function or the lens  131 , or may be provided on the IRCF  14 , the IRCF glass substrate  14 ′, the glass substrate  231 , the lens group  171 , the lenses  271  and  291 , the infrared cut resin  211 , the infrared cut lens  301 , or others. In this case, note that the black mask may be provided on a surface having low flatness by ink jet, for example, in a case where the black mask is difficult to form by photolithography due to low flatness of the surface. 
     As described above, according to the present disclosure, a flare and a ghost caused by internal diffused reflection of light from a solid-state imaging element as a result of miniaturization can be reduced. Moreover, high pixelization, high image quality, and miniaturization are achievable without deteriorating performance of the imaging device. 
     15. Fifteenth Embodiment 
     According to the examples described above, the lens  131 ,  271 , or  291 , the lens group  171 , or the infrared cut lens  301  is joined onto the solid-state imaging element  11  having a square shape by bonding, affixing, or other methods. 
     However, when any one of the lenses  131 ,  271 , and  291 , the lens group  171 , and the infrared cut lens  301  each having a square shape is bonded or affixed onto the solid-state imaging element  11  having substantially the same size, portions close to corners are easily separated. The separation of the corners of the lens  131  prevents appropriate entrance of incident light into the solid-state imaging element  11 , and may cause generation of a flare or a ghost. 
     Accordingly, in a case where any one of the lenses  131 ,  271 , and  291 , the lens group  171 , and the infrared cut lens  301  each having a square shape is bonded or affixed to the solid-state imaging element  11 , an external size of the bonded or affixed lens or lens group may be set to a size smaller than an external size of the solid-state imaging element  11 . Further, an effective region may be defined in the vicinity of the center of the lens, and a non-effective region may be defined in an outer peripheral portion of the lens. In this manner, likeliness of separation may be lowered, or incident light may be effectively converged even with slight separation of end portions. 
     Specifically, in a case where the lens  131  is bonded or affixed to the glass substrate  12  provided on the solid-state imaging element  11 , the external size of the lens  131  is made smaller than the external size of the glass substrate  12  on the solid-state imaging element  11  as depicted in  FIG. 23 , for example. In addition, a non-effective region  131   b  is defined in an outer peripheral portion of the lens  131 , and an effective region  131   a  is defined inside the non-effective region  131   b . Note that the glass substrate  231  may be provided on the solid-state imaging element  11  instead of the glass substrate  12 . 
     Moreover, the configuration of  FIG. 23  is a configuration where the IRCF  14  and the adhesive  15  are eliminated from the integrated configuration unit  10  of the imaging device  1  of  FIG. 9 . However, this elimination is made only for convenience of explanation. Needless to say, the IRCF  14  and the adhesive  15  may be provided between the lens  131  and the glass substrate  12 . 
     Furthermore, the effective region  131   a  here is a region having an aspherical shape and included in a region into which incident light of the lens  131  enters, and effectively performs a function of converging incident light on a region where photoelectric conversion is allowed in the solid-state imaging element  11 . In other words, the effective region  131   a  is a region which has a concentric structure including an aspherical lens structure, circumscribes the lens outer peripheral portion, and converges incident light on the imaging surface where photoelectric conversion is allowed in the solid-state imaging element  11 . 
     On the other hand, the non-effective region  131   b  is a region which does not necessarily functions as a lens for converging light having entered the lens  131  on the region where photoelectric conversion is performed in the solid-state imaging element  11 . 
     However, it is preferable that the non-effective region  131   b  has an extended structure functioning as an aspherical lens at a part of a boundary with the effective region  131   a . By providing the extended structure functioning as a lens in the non-effective region  131   b  in the vicinity of the boundary with the effective region  131   a , incident light can be appropriately converged on the imaging surface of the solid-state imaging element  11  even when positional deviation is produced at the time of bonding or affixing of the lens  131  to the glass substrate  12  on the solid-state imaging element  11 . 
     Note that the glass substrate  12  on the solid-state imaging element  11  is sized to have a height Vsx in the vertical direction (Y direction), and a width Hs in the horizontal direction (X direction) in  FIG. 23 , and that the lens  131  sized to have a height Vnx in the vertical direction and a width Hn in the horizontal direction, both sizes smaller than the corresponding sizes of the solid-state imaging element  11  (glass substrate  12 ), is bonded or affixed to a central portion inside the glass substrate  12  on the solid-state imaging element  11 . Further, the non-effective region  131   b  not functioning as a lens is defined in the outer peripheral portion of the lens  131 , and the effective region  131   a  sized to have a height Vex in the vertical direction and a width He in the horizontal direction is defined inside the non-effective region  131   b.    
     In other words, a relation of “the width and the length of the effective region  131   a  of the lens  131 &lt;the width and the length of the non-effective region  131   b &lt;the width and the length of the external size of (the glass substrate  12 ) on the solid-state imaging element  11 ” holds for each of the width in the horizontal direction and the height in the vertical direction. Center positions of the lens  131 , the effective region  131   a , and the non-effective region  131   b  are substantially identical. 
     Further, in  FIG. 23 , an upper part of the figure is a top view as viewed from the incident side when the lens  131  is bonded or affixed to the glass substrate  12  on the solid-state imaging element  11 , while a lower left part of the figure is an external appearance perspective view when the lens  131  is bonded or affixed to the glass substrate  12  on the solid-state imaging element  11 . 
     Further, a lower right part of  FIG. 23  is an external appearance perspective view when the lens  131  is bonded or affixed to the glass substrate  12  on the solid-state imaging element  11 . This figure depicts an end portion including a boundary B 1  between a side surface portion of the lens  131  and the glass substrate  12 , a boundary B 2  on the outside of the non-effective region  131   b , and a boundary B 3  between the outside of the effective region  131   a  and the inside of the non-effective region  131   b.    
       FIG. 23  here depicts an example where a side end portion of the lens  131  is perpendicular to the glass substrate  12  on the solid-state imaging element  11 . In the top view of  FIG. 23 , therefore, the boundary B 2  on the outside of the non-effective region  131   b  is formed in a top surface portion of the lens  131 , while the boundary B 1  between the effective region  131   a  and the non-effective region  131   b  is formed in a bottom surface portion of the lens  131 . In this case, the boundary B 1  and the boundary B 2  have the same size. Accordingly, in the upper part of  FIG. 23 , the outer peripheral portion (boundary B 1 ) of the lens  131 , and the outer peripheral portion (boundary B 2 ) of the non-effective region  131   b  are expressed as an identical external shape. 
     According to such a configuration, a space is produced between the side surface forming the outer peripheral portion of the lens  131  and the outer peripheral portion of the glass substrate  12  on the solid-state imaging element  11 . In this case, interference between the side surface portion of the lens  131  and another object can be reduced. Accordingly, likeliness of separation from the glass substrate  12  on the solid-state imaging element  11  can be lowered in this configuration. 
     Moreover, the effective region  131   a  of the lens  131  is defined inside the non-effective region  131   b . Accordingly, incident light can be appropriately converged on the imaging surface of the solid-state imaging element  11  even when the peripheral portion is slightly separated. Furthermore, interface reflection increases when the lens  131  is separated. In this case, a flare or a ghost becomes worse. Accordingly, reduction of separation can consequently reduce generation of a flare or a ghost. 
     While the example where the lens  131  is bonded or affixed to the glass substrate  12  on the solid-state imaging element  11  has been described with reference to  FIG. 23 , any one of the lenses  271  and  291 , the lens group  171 , and the infrared cut lens  301  may be obviously bonded or affixed instead of the lens  131 . 
     &lt;Modification of Lens External Shape&gt; 
     According to the example described above, the effective region  131   a  is defined at the central portion of the lens  131 , the non-effective region  131   b  is defined in the outer peripheral portion of the lens  131 , and the size of the effective region  131   a  is smaller than the outer peripheral size of (the glass substrate  12  on) the solid-state imaging element  11 . In addition, each of the four corners of the external shape of the lens  131  has an acute angle. 
     However, the external shape may be other shapes as long as the external shape is formed such that the size of the lens  131  is smaller than the size of (the glass substrate  12  on) the solid-state imaging element  11 , that the effective region  131   a  is defined at the central portion of the lens  131 , and that the non-effective region  131   b  is defined in the outer peripheral portion of the lens  131 . 
     In other words, as depicted in an upper left part of  FIG. 24  (corresponding to  FIG. 23 ), a region Z 301  at each of the four corners of the external shape of the lens  131  may have a shape having an acute angle. Further, as depicted in a lens  131 ′ in an upper right part of  FIG. 24 , a region Z 302  at each of the four corners may have a polygonal shape having an obtuse angle. 
     Further, as depicted in a lens  131 ″ in a middle left part of  FIG. 24 , a region Z 303  at each of the four corners of the external shape may have a circular shape. 
     Further, as depicted in a lens  131 ′″ in a middle right part of  FIG. 24 , a region Z 304  at each of the four corners of the external shape may have a small square portion protruded from the corresponding one of the four corners. Besides, the protruded portion may have shapes other than the square shape, such as a circular shape, an elliptical shape, and a polygonal shape. 
     Moreover, as depicted in a lens  131 ″″ in a lower left part of  FIG. 24 , a region Z 305  at each of the four corners of the external shape may have a square recess. 
     Furthermore, as depicted in a lens  131 ′″ in a lower right part of  FIG. 24 , the effective region  131   a  may have a square shape, and the peripheral portion outside the non-effective region  131   b  may have a circular shape. 
     Generally, the corners of the lens  131  are more easily separated from the glass substrate  12  as the angles of the corners become acuter. In this case, optically adverse effects may be produced. Accordingly, as depicted in the lenses  131 ′ to  131 ′″″ in  FIG. 24 , the corners each have a polygonal shape having an obtuse angle larger than 90 degrees, a round shape, a recessed shape, a protruding shape, or the like to produce a configuration lowering likeliness of separation of the lens  131  from the glass substrate  12 . In this manner, a risk of optically adverse effects can be lowered. 
     &lt;Modified Examples of Lens End Portion Structure&gt; 
     According to the example described above, the end portion of the lens  131  is formed perpendicularly to the imaging surface of the solid-state imaging element  11 . However, other shapes may be adopted as long as the external shape is formed such that the size of the lens  131  is smaller than the size of the solid-state imaging element  11 , that the effective region  131   a  is defined at the central portion of the lens  131 , and that the non-effective region  131   b  is defined in the outer peripheral portion of the lens  131 . 
     Specifically, as depicted in an upper left part of  FIG. 25 , a configuration similar to the effective region  131   a  as an aspherical lens may be extended in the non-effective region  131   b  at the boundary with the effective region  131   a , and the end portion may be perpendicularly formed as indicated by an end portion Z 331  of the non-effective region  131   b  (corresponding to the configuration of  FIG. 23 ). 
     In addition, as depicted in an upper second part from the left in  FIG. 25 , a configuration similar to the effective region  131   a  as an aspherical lens may be extended in the non-effective region  131   b  at the boundary with the effective region  131   a , and the end portion may have a tapered shape as indicated by an end portion Z 332  of the non-effective region  131   b.    
     Further, as depicted in an upper third part from the left in  FIG. 25 , a configuration similar to the effective region  131   a  as an aspherical lens may be extended in the non-effective region  131   b  at the boundary with the effective region  131   a , and the end portion may have a round shape as indicated by an end portion Z 333  of the non-effective region  131   b.    
     Further, as depicted in an upper right part in  FIG. 25 , a configuration similar to the effective region  131   a  as an aspherical lens may be extended in the non-effective region  131   b  at the boundary with the effective region  131   a , and the end portion may be a side surface having a multistep structure as indicated by an end portion Z 334  of the non-effective region  131   b.    
     Further, as depicted in a lower left part in  FIG. 25 , a configuration similar to the effective region  131   a  as an aspherical lens may be extended in the non-effective region  131   b  at the boundary with the effective region  131   a , and the end portion may have a flat surface portion in the horizontal direction as indicated by an end portion Z 335  of the non-effective region  131   b . In addition, a protruding portion having a bank shape and protruding in a direction opposite to the incident direction of incident light from the effective region  131   a  may be formed, and a side surface of this protruding portion may be perpendicularly formed. 
     Moreover, as depicted in a lower second part from the left in  FIG. 25 , a configuration similar to the effective region  131   a  as an aspherical lens may be extended in the non-effective region  131   b  at the boundary with the effective region  131   a , and the end portion may have a flat surface portion in the horizontal direction as indicated by an end portion Z 336  of the non-effective region  131   b . In addition, a protruding portion having a bank shape and protruding in a direction opposite to the incident direction of incident light from the effective region  131   a  may be formed, and a side surface of this protruding portion may have a tapered shape. 
     Additionally, as depicted in a lower third part from the left in  FIG. 25 , a configuration similar to the effective region  131   a  as an aspherical lens may be extended in the non-effective region  131   b  at the boundary with the effective region  131   a , and an end portion may have a flat surface portion in the horizontal direction as indicated by an end portion Z 337  of the non-effective region  131   b . In addition, a protruding portion having a bank shape and protruding in a direction opposite to the incident direction of incident light from the effective region  131   a  may be formed, and a side surface of this protruding portion may have a round shape. 
     Furthermore, as depicted in a lower right part in  FIG. 25 , a configuration similar to the effective region  131   a  as an aspherical lens may be extended in the non-effective region  131   b  at the boundary with the effective region  131   a , and the end portion may have a flat surface portion in the horizontal direction as indicated by an end portion Z 338  of the non-effective region  131   b . In addition, a protruding portion having a bank shape and protruding in a direction opposite to the incident direction of incident light from the effective region  131   a  may be formed, and a side surface of this protruding portion may have a multistep structure. 
     Note that the upper part of  FIG. 25  depicts structure examples each of which does not include a protruding portion having a flat surface portion in the horizontal direction at the end portion of the lens  131  and having a bank shape which protrudes in the direction opposite to the incident direction of incident light from the effective region  131   a , while the lower part of  FIG. 25  depicts structure examples each of which does not include a protruding portion having a flat surface portion in the horizontal direction at the end portion of the lens  131 . Further, each of the upper part and the lower part of  FIG. 25  depicts a configuration example where the end portion of the lens  131  is perpendicular to the glass substrate  12 , a configuration example where the end portion has a tapered shape, a configuration example where the end portion has a round shape, and a configuration example where the end portion has a multistep forming a plurality of side surfaces. 
     Further, as depicted in an upper part of  FIG. 26 , a configuration similar to the effective region  131   a  as an aspherical lens may be extended in the non-effective region  131   b  at the boundary with the effective region  131   a , and a protruding portion may be perpendicularly formed with respect to the glass substrate  12  as indicated by an end portion Z 351  of the non-effective region  131   b . In addition, a boundary structure Es having a square shape may be left at the boundary with the glass substrate  12  on the solid-state imaging element  11 . 
     Besides, as depicted in a lower part of  FIG. 26 , a configuration similar to the effective region  131   a  as an aspherical lens may be extended in the non-effective region  131   b  at the boundary with the effective region  131   a , and a protruding portion may be perpendicularly formed with respect to the glass substrate  12  as indicated by an end portion Z 352  of the non-effective region  131   b . In addition, a boundary structure Er having a round shape may be left at the boundary with the glass substrate  12  on the solid-state imaging element  11 . 
     In each of the boundary structure Es having a square shape and the boundary structure Er having a round shape, the lens  131  and the glass substrate  12  can be more tightly joined to each other by increasing a contact area between the lens  131  and the glass substrate  12 . As a result, separation of the lens  131  from the glass substrate  12  can be reduced. 
     Note that each of the boundary structure Es having a square shape and the boundary structure Er having a round shape may be adopted in any of the case where the end portion has a tapered shape, the case where the end portion has a round shape, and the case where the end portion has a multistep structure. 
     Further, as depicted in  FIG. 27 , a configuration similar to the effective region  131   a  as an aspherical lens may be extended in the non-effective region  131   b  at the boundary with the effective region  131   a , and the side surface of the lens  131  may be perpendicularly formed with respect to the glass substrate  12  as indicated by an end portion Z 371  of the non-effective region  131   b . In addition, a refractive film  351  having a predetermined refractive index may be formed at substantially the same height as the height of the lens  131  on the glass substrate  12  in the outer peripheral portion of the side surface. 
     In this manner, in a case where the refractive film  351  has a higher refractive index than a predetermined refractive index, for example, incident light coming from the outer peripheral portion of the lens  131  is reflected to the outside of the lens  131  as indicated by a solid arrow in an upper part of  FIG. 27 . In addition, incident light toward the side surface portion of the lens  131  is decreased as indicated by a dotted arrow. As a result, entrance of stray light into the lens  131  is reduced, and therefore generation of a flare or a ghost is reduced. 
     Further, in a case where the refractive film  351  has a lower refractive index than the predetermined refractive index, light not entering the incident surface of the solid-state imaging element  11  but attempting to pass through the side surface of the lens  131  to the outside of the lens  131  is transmitted as indicated by a solid arrow in a lower part of  FIG. 27 . In addition, reflection light coming from the side surface of the lens  131  is decreased as indicated by a dotted arrow. As a result, entrance of stray light into the lens  131  is reduced, and therefore reduction of generation of a flare or a ghost is achievable. 
     Further, according to the example described above with reference to  FIG. 27 , the refractive film  351  is formed at the same height as the height of the lens  131  on the glass substrate  12 , and the end portion of the refractive film  351  is perpendicularly formed. However, other shapes may be adopted. 
     For example, as depicted in a region Z 391  in an upper left part of  FIG. 28 , the refractive film  351  may have a tapered end portion on the glass substrate  12 , and have a thickness to become higher than the height of the end portion of the lens  131 . 
     Further, for example, as depicted in a region Z 392  in an upper center part of  FIG. 28 , the refractive film  351  may have a tapered end portion, and have a thickness to become higher than the height of the end portion of the lens  131 . Further, a part of the refractive film  351  may overlap with the non-effective region  131   b  of the lens  131 . 
     Moreover, for example, as depicted in a region Z 393  in an upper right part of  FIG. 28 , the refractive film  351  may have a tapered shape extending from the height of the end portion of the lens  131  to the end portion of the glass substrate  12 . 
     Additionally, for example, as depicted in a region Z 394  in a lower left part of  FIG. 28 , the refractive film  351  may have a tapered portion at the end portion of the glass substrate  12 , and have a thickness to become lower than the height of the end portion of the lens  131 . 
     Furthermore, for example, as depicted in a region Z 395  in a lower right part of  FIG. 28 , the refractive film  351  may have a portion recessed toward the glass substrate  12  from the height of the end portion of the lens  131 , and have a round shape. 
     Any configurations of  FIGS. 27 and 28  reduces entrance of stray light into the lens  131 . Accordingly, reduction of generation of a flare or a ghost is achievable. 
     16. Sixteenth Embodiment 
     According to the example described above, a flare or a ghost is reduced by lowering likeliness of separation of the lens  131  from the glass substrate  12  or reducing entrance of stray light. However, a flare or a ghost may be reduced by decreasing a burr of an adhesive produced during processing. 
     Specifically, considered here is a case where the glass substrate  12  is bonded onto the IRCF  14  via the adhesive  15  in a state where the IRCF  14  is provided on the solid-state imaging element  11  (for example, the configuration of the seventh embodiment of  FIG. 15 ) as depicted in an upper part of  FIG. 29 . Note that the configuration of  FIG. 29  corresponds to the configuration of the integrated configuration unit  10  included in the imaging device  1  of  FIG. 15  other than the lens. 
     In this case, the IRCF  14  requires a predetermined film thickness. However, viscosity of the material of the IRCF  14  is generally difficult to increase, and a desired film thickness is difficult to obtain at a time. However, overcoating produces microvoids or air entrainment, and may deteriorate optical characteristics. 
     Further, the glass substrate  12  is bonded via the adhesive  15  after the IRCF  14  is formed on the solid-state imaging element  11 . In this case, a warp is produced by cure shrinkage of the IRCF  14 , and a junction failure may be caused between the glass substrate  12  and the IRCF  14 . Further, the warp of the IRCF  14  is difficult to correct only by the glass substrate  12 . Accordingly, the entire device is warped, and optical characteristics may be deteriorated. 
     Further, particularly in a case where the glass substrate  12  and the IRCF  14  are joined to each other via the adhesive  15 , a resin burr is produced from the adhesive  15  during individualization as indicated by a range Z 411  in an upper part of  FIG. 29 . In this case, working accuracy may be lowered during mounting such as picking up. 
     Accordingly, as depicted in a middle part of  FIG. 29 , the IRCF  14  is divided into two parts constituted by IRCFs  14 - 1  and  14 - 2 , and the IRCFs  14 - 1  and  14 - 2  are bonded to each other via the adhesive  15 . 
     According to such a configuration, each of the IRCF  14 - 1  and  14 - 2  can be divided and formed into a thin film during film formation. Accordingly, thick film formation for obtaining desired spectral characteristics (divisional formation) is facilitated. 
     In addition, when the glass substrate  12  is joined to the solid-state imaging element  11 , a step on the solid-state imaging element  11  (sensor step such as PAD) can be flattened by the IRCF  14 - 2  before joining the glass substrate  12 . Accordingly, the film thickness of the adhesive  15  can be reduced, and consequently the height of the imaging device  1  can be reduced. 
     Further, a warp is cancelled by the IRCFs  14 - 1  and  14 - 2  formed on the glass substrate  12  and the solid-state imaging element  11 , respectively. Accordingly, a warp of a device chip can be reduced. 
     Moreover, elastic modulus of glass is higher than that of the IRCFs  14 - 1  and  14 - 2 . When the elastic modulus of the IRCFs  14 - 1  and  14 - 2  is higher than the elastic modulus of the adhesive  15 , the upper side and the lower side of the adhesive  15  having low elasticity are covered by the IRCFs  14 - 1  and  14 - 2  having higher elasticity than that of the adhesive  15  during individualization. Accordingly, generation of a resin burr can be reduced during individualization (expansion) as indicated as a range Z 412  in an upper part of  FIG. 29 . 
     Furthermore, as depicted in a lower part of  FIG. 29 , IRCFs  14 ′- 1  and  14 ′- 2  each having a function of an adhesive may be formed for direct affixation in a mutually opposed state. In such a manner, generation of a resin burr from the adhesive  15  during individualization can be reduced. 
     &lt;Manufacturing Method&gt; 
     Described next with reference to  FIG. 30  will be a manufacturing method which joins the glass substrate  12  to the solid-state imaging element  11  depicted in the middle part of  FIG. 29  using the IRCFs  14 - 1  and  14 - 2  with the adhesive  15  interposed. 
     In a first step, the IRCF  14 - 1  is applied to and formed on the glass substrate  12  as depicted in an upper left part of  FIG. 30 . In addition, the IRCF  14 - 2  is applied to and formed on the solid-state imaging element  11 . Note that the glass substrate  12  in the upper left part of  FIG. 30  is depicted in a state that the top and the bottom are reversed after the IRCF  14 - 2  is applied. 
     In a second step, the adhesive  15  is applied onto the IRCF  14 - 2  as depicted in an upper center part of  FIG. 30 . 
     In a third step, the IRCF  14 - 1  on the glass substrate  12  is affixed onto the adhesive  15  depicted in the upper center part of  FIG. 30  in such a manner as to face the surface to which the adhesive  15  has been applied as depicted in an upper right part of  FIG. 30 . 
     In a fourth step, an electrode is provided on the back side of the solid-state imaging element  11  as depicted in a lower left part of  FIG. 30 . 
     In a fifth step, the glass substrate  12  is thinned by polishing as depicted in a center lower part of  FIG. 30 . 
     Subsequently, after the fifth step, end portions are cut by a blade or the like for individualization to complete the solid-state imaging element  11  which includes the IRCFs  14 - 1  and  14 - 2  laminated on the imaging surface, and the glass substrate  12  provided on the lamination of the IRCFs  14 - 1  and  14 - 2 . 
     The adhesive  15  is sandwiched between the IRCFs  14 - 1  and  14 - 2  by the above steps. Accordingly, a burr produced by individualization can be reduced. 
     Further, each of the IRCFs  14 - 1  and  14 - 2  is allowed to constitute a half of a necessary film thickness. In this case, a thickness requiring overcoating can be reduced, or the necessity of overcoating is eliminated. Accordingly, deterioration of optical characteristics can be reduced by reduction of microvoids or air entrainment. 
     Further, with the decrease in each film thickness of the IRCFs  14 - 1  and  14 - 2 , a warp caused by cure shrinkage is allowed to decrease. Accordingly, deterioration of optical characteristics caused by a warp can be reduced by reduction of a junction failure between the glass substrate  12  and the IRCF  14 . 
     Note that only a step of applying the adhesive  15  is skipped in a case of use of the IRCFs  14 ′- 1  and  14 ′- 2  having a function of an adhesive as depicted in a lower part of  FIG. 29 . Accordingly, description of this case is omitted. 
     &lt;Modified Examples of Side Surface Shape after Individualization&gt; 
     It is assumed that the end portion of the solid-state imaging element  11  is cut by a blade or the like such that a side surface cross section becomes perpendicular to the imaging surface at the time of individualization of the solid-state imaging element  11  where the IRCFs  14 - 1  and  14 - 2  and further the glass substrate  12  are provided by the manufacturing method described above. 
     However, an effect of falling wastes produced by the glass substrate  12 , the IRCFs  14 - 1  and  14 - 2 , and the adhesive  15  may be further reduced by adjusting shapes of side surface cross sections of the IRCFs  14 - 1  and  14 - 2  and the glass substrate  12  provided on the solid-state imaging element  11 . 
     For example, as depicted in an upper let part of  FIG. 31 , the side surface cross sections may be formed such that the external shape of the solid-state imaging element  11  in the horizontal direction becomes the largest, and that the glass substrate  12 , the IRCFs  14 - 1  and  14 - 2 , and the adhesive  15  are equalized and become smaller than the solid-state imaging element  11 . 
     In addition, as depicted in an upper right part of  FIG. 31 , the side surface cross sections may be formed such that the external shape of the solid-state imaging element  11  in the horizontal direction becomes the largest, that the external shapes of the IRCFs  14 - 1  and  14 - 2  and the adhesive  15  are equalized and become largest next to the solid-state imaging element  11 , and that the external shape of the glass substrate  12  becomes the smallest. 
     Moreover, as depicted in a lower left part of  FIG. 31 , the side surface cross sections may be formed such that the sizes of the external shapes in the horizontal direction change in a descending order of the solid-state imaging element  11 , the IRCFs  14 - 1  and  14 - 2 , the adhesive  15 , and the glass substrate  12 . 
     Furthermore, as depicted in a lower right part of  FIG. 31 , the side surface cross sections may be formed such that the external shape of the solid-state imaging element  11  in the horizontal direction becomes the largest, that the external shape of the glass substrate  12  becomes the largest next to the solid-state imaging element  11 , and that the external shapes of the IRCFs  14 - 1  and  14 - 2  and the adhesive  15  are equalized and become the smallest. 
     &lt;Individualization Method of Upper Left Part of FIG.  31 &gt; 
     An individualization method of the upper left part of  FIG. 31  will be subsequently described with reference to  FIG. 32 . 
     A diagram depicted in an upper part of  FIG. 32  is a diagram explaining the side surface cross section depicted in the upper left part of  FIG. 31 . Specifically, as depicted in the side surface cross section in the upper part of  FIG. 32 , the external shape of the solid-state imaging element  11  in the horizontal direction is the largest, and the glass substrate  12 , the IRCFs  14 - 1  and  14 - 2 , and the adhesive  15  are equalized in size and are smaller than the solid-state imaging element  11 . 
     A forming method of the side surface cross section depicted in the upper left part of  FIG. 31  will be here described with reference to a middle part of  FIG. 32 . Note that the middle part of  FIG. 32  is an enlarged diagram of a boundary between the adjoining solid-state imaging elements  11  cut for individualization as viewed from the side surface. 
     In a first step, a range Zb constituted by the glass substrate  12 , the IRCFs  14 - 1  and  14 - 2 , and the adhesive  15  is cut from a surface layer of the IRCF  14 - 1  up to a depth Lc 1  by using a blade having a predetermined width Wb (e.g., approximately 100 μm) at the boundary between the adjoining solid-state imaging elements  11 . 
     A position corresponding to the depth Lc from the surface layer of the IRCF  14 - 1  in a center part of  FIG. 32  here is defined as a position in a surface layer of the solid-state imaging element  11  and up to a wiring layer  11 M formed by CU-CU junction or the like. However, the position is only required to reach the surface layer of the solid-state imaging element  11 . Accordingly, the depth Lc 1  may be a position cut up to a surface layer of the semiconductor substrate  81  of  FIG. 6 . 
     Further, as depicted in the center part of  FIG. 32 , the blade cuts the boundary in such a state as to be centered at a center position of the adjoining solid-state imaging elements  11  as indicated by a one-dot chain line. Further, a width WLA in the figure is a width where wiring layers provided at ends of the adjoining two solid-state imaging elements  11  are formed. In addition, a width up to a center of a scribe line of one of chips of the solid-state imaging elements  11  is a width Wc, while a width up to an end of the glass substrate  12  is a width Wg. 
     Moreover, the range Zb corresponds to a shape of the blade. An upper portion of the range Zb is defined by the width Wb of the blade, while the lower portion is expressed as a semispherical shape. The shape of the range Zb corresponds to the shape of the blade. 
     In a second step, an Si substrate (semiconductor substrate  81  of  FIG. 6 ) of the solid-state imaging element  11  is cut in a range Zh having a predetermined width Wd (e.g., approximately 35 μm) smaller than the width of the blade having cut the glass substrate  12  by dry etching, laser dicing, or using a blade, for example, for individualization of the solid-state imaging element  11 . However, in a case of laser dicing, the width Wd becomes substantially zero. Moreover, a cutting shape is adjustable to a desired shape by dry etching, laser dicing, or using the blade. 
     As a result, as depicted in a lower part of  FIG. 32 , the side surface cross section is formed such that the external shape of the solid-state imaging element  11  in the horizontal direction becomes the largest, and that the glass substrate  12 , the IRCFs  14 - 1  and  14 - 2 , and the adhesive  15  are equalized and become smaller than the solid-state imaging element  11 . 
     Note that a part of the IRCF  14 - 2  in the horizontal direction in the vicinity of the boundary with the solid-state imaging element  11  has a larger width than the width of the IRCF  14 - 1  in the horizontal direction as depicted in a range Z 431  in the lower part of  FIG. 32 , and has a shape different from each shape of the side surface cross sections of the glass substrate  12 , the IRCFs  14 - 1  and  14 - 2 , and the adhesive  15  in the upper part of  FIG. 32 . 
     However, this difference is produced as a result of deformation of the cutting shape using the blade. The configuration in the lower part of  FIG. 32  can be made substantially equivalent to the configuration in the upper part of  FIG. 32  by adjusting the cutting shape using dry etching, laser dicing, or using the blade. 
     Moreover, the process of cutting the Si substrate (semiconductor substrate  81  of  FIG. 6 ) constituting the solid-state imaging element  11  in the range Zh may be executed prior to the work of cutting the range Zb. At this time, the work may be performed in a state that the top and the bottom are reversed with respect to the state in the middle part of  FIG. 32 . 
     Furthermore, generation of cracks or film separation of the wiring layer is likely to occur during blade dicing. Accordingly, the range Zh may be cut by abrasion processing using short pulse laser. 
     &lt;Individualization Method of Upper Right Part of FIG.  31 &gt; 
     An individualization method of the upper right part of  FIG. 31  will be subsequently described with reference to  FIG. 33 . 
     A diagram depicted in an upper part of  FIG. 33  is a diagram explaining the side surface cross section depicted in the upper right part of  FIG. 31 . Specifically, as depicted in the side surface cross section in the upper part of  FIG. 33 , the external shape of the solid-state imaging element  11  in the horizontal direction is the largest, the external shapes of the IRCFs  14 - 1  and  14 - 2  and the adhesive  15  are equalized and are the largest next to the solid-state imaging element  11 , and the external shape of the glass substrate  12  is the smallest. 
     A forming method of the side surface cross section depicted in the upper right part of  FIG. 31  will be here described with reference to a middle part of  FIG. 33 . Note that the middle part of  FIG. 33  is an enlarged diagram of a boundary between the adjoining solid-state imaging elements  11  cut for individualization as viewed from the side surface. 
     In a first step, a range Zb 1  constituted by the glass substrate  12 , the IRCFs  14 - 1  and  14 - 2 , and the adhesive  15  is cut from the surface layer of the IRCF  14 - 1  up to a depth Lc 11  by using a blade having a predetermined width Wb 1  (e.g., approximately 100 μm) at the boundary of the adjoining solid-state imaging elements  11 . 
     In a second step, a range Zb 2  having a depth exceeding the wiring layer  11 M is cut by a blade having a predetermined width Wb 2  (&lt;width Wb 1 ). 
     In a third step, the Si substrate (semiconductor substrate  81  in  FIG. 6 ) is cut in the range Zh having the predetermined width Wd (e.g., approximately 35 μm) smaller than the width Wb 2  by dry etching, laser dicing, or using a blade, for example, for individualization of the solid-state imaging element  11 . However, in a case of laser dicing, the width Wd becomes substantially zero. Moreover, a cutting shape is adjustable to a desired shape by dry etching, laser dicing, or using the blade. 
     As a result, as depicted in a lower part of  FIG. 33 , the side surface cross section is formed such that the external shape of the solid-state imaging element  11  in the horizontal direction becomes the largest, that the IRCFs  14 - 1  and  14 - 2  and the adhesive  15  are equalized and become the largest next to the solid-state imaging element  11 , and that the glass substrate  12  becomes the smallest. 
     Note that a part of the IRCF  14 - 1  in the horizontal direction has the same width as the width of the glass substrate  12  in the horizontal direction as indicated by a range Z 441  in the lower part of  FIG. 33 . In addition, a part of the IRCF  14 - 2  in the horizontal direction has a larger width than the width of the IRCF  14 - 1  as indicated by a range Z 442 . 
     Accordingly, the shapes of the side cross sections of the glass substrate  12 , the IRCFs  14 - 1  and  14 - 2 , and the adhesive  15  are different from the corresponding shapes in the upper part of  FIG. 33 . 
     However, this difference is produced as a result of deformation of the cutting shape using the blade. The configuration in the lower part of  FIG. 32  can be made substantially equivalent to the configuration in the upper part of  FIG. 32  by adjusting the cutting shape using dry etching, laser dicing, or using the blade. 
     Moreover, the process of cutting the Si substrate (semiconductor substrate  81  of  FIG. 6 ) constituting the solid-state imaging element  11  in the range Zh may be executed prior to the work of cutting the ranges Zb 1  and Zb 2 . At this time, the work may be performed in a state where the top and the bottom are reversed with respect to the state in the middle part of  FIG. 33 . 
     Furthermore, generation of cracks or film separation of the wiring layer is likely to occur during blade dicing. Accordingly, the range Zh may be cut by abrasion processing using short pulse laser. 
     &lt;Individualization Method of Lower Left Part of FIG.  31 &gt; 
     An individualization method of the lower left part of  FIG. 31  will be subsequently described with reference to  FIG. 34 . 
     A diagram depicted in an upper part of  FIG. 34  is a diagram explaining the side surface cross section depicted in the lower left part of  FIG. 31 . Specifically, as depicted in the side surface cross section in the upper left part of  FIG. 34 , the size of the external shape decreases in an order of the external shape of the solid-state imaging element  11  in the horizontal direction, the IRCFs  14 - 1  and  14 - 2 , the adhesive  15 , and the glass substrate  12 . 
     A forming method of the side surface cross section depicted in the upper right part of  FIG. 31  will be here described with reference to a middle part of  FIG. 34 . Note that the middle part of  FIG. 34  is an enlarged diagram of a boundary between the adjoining solid-state imaging elements  11  cut for individualization as viewed from the side surface. 
     In a first step, the range Zb constituted by the glass substrate  12 , the IRCFs  14 - 1  and  14 - 2 , and the adhesive  15  is cut from the surface layer of the IRCF  14 - 2  up to a depth Lc 21  by using a blade having the predetermined width Wb 1  (e.g., approximately 100 μm). 
     In a second step, a range ZL having a depth exceeding the wiring layer  11 M is cut by abrasion processing using laser by the predetermined width Wb 2  (&lt;width Wb 1 ). 
     In this step, the IRCFs  14 - 1 ,  14 - 2 , and the adhesive  15  cause thermal contraction as a result of absorption of laser beams in the vicinity of the processing surface. In this case, the adhesive  15  moves backward from the cutting surfaces of the IRCFs  14 - 1  and  14 - 2  and has a recessed shape according to wavelength dependence. 
     In a third step, the Si substrate (semiconductor substrate  81  in  FIG. 6 ) is cut in the range Zh having a predetermined width Wd (e.g., approximately 35 μm) smaller than the width Wb 2  by dry etching, laser dicing, or using a blade, for example, for individualization of the solid-state imaging element  11 . However, in a case of laser dicing, the width Wd becomes substantially zero. Moreover, a cutting shape is adjustable to a desired shape by dry etching, laser dicing, or using the blade. 
     As a result, as depicted in a lower part of  FIG. 34 , the side surface cross section is formed such that the external shape of the solid-state imaging element  11  in the horizontal direction becomes the largest, that the external shapes of the IRCFs  14 - 1  and  14 - 2  become the largest next to the solid-state imaging element  11 , that the external shape of the adhesive  15  becomes the largest next to the IRCFs  14 - 1  and  14 - 2 , and that the glass substrate  12  becomes the smallest. In other words, as indicated by a range Z 452  in a lower part of  FIG. 34 , the external shape of the adhesive  15  is smaller than the external shapes of the IRCFs  14 - 1  and  14 - 2 . 
     In the lower part of  FIG. 34 , note that a part of the IRCF  14 - 2  in the horizontal direction has a larger width than the width of the IRCF  14 - 1  in the horizontal direction as indicated by a range Z 453 . In addition, a part of the IRCF  14 - 1  in the horizontal direction has the same width as the width of the glass substrate  12  in the horizontal direction as indicated by a range Z 451 . 
     Accordingly, the shapes of the side cross sections of the glass substrate  12 , the IRCFs  14 - 1  and  14 - 2 , and the adhesive  15  in the lower part of  FIG. 34  are different from the corresponding shapes in the upper part of  FIG. 34 . 
     However, this difference is produced as a result of deformation of the cutting shape using the blade. The configuration in the lower part of  FIG. 32  can be made substantially equivalent to the configuration in the upper part of  FIG. 32  by adjusting the cutting shape using dry etching, laser dicing, or using the blade. 
     Moreover, the process of cutting the Si substrate (semiconductor substrate  81  of  FIG. 6 ) constituting the solid-state imaging element  11  in the range Zh may be executed prior to the work of cutting the ranges Zb and ZL. At this time, the work may be performed in a state where the top and the bottom are reversed with respect to the state in the middle part of  FIG. 34 . 
     Furthermore, generation of cracks or film separation of the wiring layer is likely to occur during blade dicing. Accordingly, the range Zh may be cut by abrasion processing using short pulse laser. 
     &lt;Individualization Method of Lower Right Part of FIG.  31 &gt; 
     An individualization method of the lower right part of  FIG. 31  will be subsequently described with reference to  FIG. 35 . 
     A diagram depicted in an upper part of  FIG. 35  is a diagram explaining the side surface cross section depicted in the lower right part of  FIG. 31 . Specifically, as depicted in the side surface cross section in the upper part of  FIG. 35 , the external shape of the solid-state imaging element  11  in the horizontal direction is the largest, the external shape of the glass substrate  12  is the largest next to the solid-state imaging element  11 , and the external shapes of the IRCFs  14 - 1  and  14 - 2  and the adhesive  15  are equalized and are the smallest. 
     A forming method of the side surface cross section depicted in the lower right part of  FIG. 31  will be here described with reference to a middle part of  FIG. 35 . Note that the middle part of  FIG. 35  is an enlarged diagram of a boundary between the adjoining solid-state imaging elements  11  cut for individualization as viewed from the side surface. 
     In a first step, the glass substrate  12  in a range Zs 1  having a width Ld of substantially zero is cut by what is generally called stealth (laser) dicing using laser. 
     In a second step, abrasion processing using laser is performed for only a predetermined width Wab to cut the range ZL included in the IRCFs  14 - 1  and  14 - 2  and the solid-state imaging element  11  and reaching a depth exceeding the wiring layer  11 M. 
     In this step, processing is performed such that cutting surfaces of the IRCFs  14 - 1  and  14 - 2  and the adhesive  15  are equalized by adjusting abrasion processing using laser. 
     In a third step, a range Zs 2  having a width of substantially zero is cut by what is generally called stealth (laser) dicing using laser to individualize the solid-state imaging element  11 . At this time, organic matters produced by abrasion are discharged to the outside via a groove formed by stealth dicing. 
     As a result, as depicted in ranges Z 461  and Z 462  in a lower part of  FIG. 35 , the side surface cross section is formed such that the external shape of the solid-state imaging element  11  in the horizontal direction becomes the largest, that the external shape of the glass substrate  12  becomes the largest next to the solid-state imaging element  11 , and that the external shapes of the IRCFs  14 - 1  and  14 - 2  and the adhesive  15  are equalized and become the smallest. 
     In addition, the order of the stealth dicing processing for the glass substrate  12  and the stealth dicing processing for the solid-state imaging element  11  may be switched. In this case, working may be performed in a state where the top and the bottom are reversed with respect to the state depicted in the middle part of  FIG. 35 . 
     &lt;Addition of Anti-Reflection Film&gt; 
     According to the example described above, as depicted in an upper left part of  FIG. 36 , the IRCFs  14 - 1  and  14 - 2  are bonded to and formed on the solid-state imaging element  11  via the adhesive  15 , and the glass substrate  12  is provided on the IRCF  14 - 1 . In this manner, generation of a burr and deterioration of optical characteristics are reduced. In this case, an added film having the anti-reflection function may be further formed. 
     Specifically, for example, an added film  371  having an anti-reflection function may be provided on the glass substrate  12  as depicted in a middle left part of  FIG. 36 . 
     Moreover, for example, added films  371 - 1  to  371 - 4  each having the anti-reflection function may be provided on the glass substrate  12 , the boundary between the glass substrate  12  and the IRCF  14 - 1 , the boundary between the IRCF  14 - 1  and the adhesive  15 , and the boundary between the adhesive  15  and the IRCF  14 - 2 , respectively, as depicted in a lower left part of  FIG. 36 . 
     Furthermore, any one of the added films  371 - 2 ,  371 - 4 , and  371 - 3  each having the anti-reflection function may be formed as depicted in an upper right part, a middle right part, and a lower right part of  FIG. 36 , or the added films  371 - 2 ,  371 - 4 , and  371 - 3  may be combined and formed. 
     Note that each of the added films  371  and  371 - 1  to  371 - 4  may be constituted by a film which has a function equivalent to the function of the AR coating  271   a  described above or the function of the anti-reflection treatment portion (moth eye)  291   a , for example. 
     The added films  371  and  371 - 1  to  371 - 4  prevent entrance of unnecessary light, thereby reducing generation of a flare or a ghost. 
     &lt;Addition to Side Surface Portion&gt; 
     According to the example described above, at least any one of the glass substrate  12 , the boundary between the glass substrate  12  and the IRCF  14 - 1 , the boundary between the IRCF  14 - 1  and the adhesive  15 , or the boundary between the adhesive  15  and the IRCF  14 - 2  is equipped with the corresponding one of the added films  371 - 1  to  371 - 4  each having the anti-reflection function. However, the side surface portion may be equipped with an added film functioning as an anti-reflection film or a light absorbing film. 
     Specifically, as depicted in a left part of  FIG. 37 , the added film  381  functioning as an anti-reflection film, a light absorbing film, or the like may be provided on an entire side surface cross section of the glass substrate  12 , the IRCFs  14 - 1  and  14 - 2 , the adhesive  15 , and the solid-state imaging element  11 . 
     Moreover, as depicted in a right part of  FIG. 37 , the added film  381  functioning as an anti-reflection film, a light absorbing film, or the like may be provided on only the side surfaces of the glass substrate  12 , the IRCFs  14 - 1  and  14 - 2 , and the adhesive  15 , except for the side surface of the solid-state imaging element  11 . 
     In either of these cases, reduction of entrance of unnecessary light into the solid-state imaging element  11 , and thus reduction of generation of a ghost and a flare are achievable by the added film  381  provided on the side surface portions of the solid-state imaging element  11 , the glass substrate  12 , the IRCFs  14 - 1  and  14 - 2 , and the adhesive  15 . 
     17. Seventeenth Embodiment 
     According to the example described above, reduction of falling wastes, and also reduction of generation of a flare or a ghost are achieved by adjusting a size relation in the horizontal direction between the solid-state imaging element  11 , the IRCF  14 - 1 , the adhesive  15 , the IRCF  14 - 2 , and the glass substrate  12  laminated on each other. However, a lens which is miniaturized and lightweight and achieves high-resolution imaging may be actualized by specifying a lens shape. 
     For example, consider a case where a lens corresponding to the lens  271  coated with the AR coating  271   a  is joined onto the glass substrate  12  provided on the solid-state imaging element  11  (for example, the integrated configuration unit  10  included in the imaging device  1  of  FIG. 19 ). Note that the configuration of the imaging device  1  may be a configuration other than the configuration of  FIG. 19 . For example, the same is applicable to a case where the lens  131  included in the integrated configuration unit  10  of the imaging device  1  of  FIG. 9  is replaced with the lens  271 . 
     Specifically, as depicted in  FIG. 38 , it is assumed that a lens  401  of a recessed type having an aspherical surface concentric around a center located at a center of gravity as viewed from a top surface (corresponding to the lens  271  of  FIG. 19 ) is provided on the glass substrate  12  formed on the solid-state imaging element  11 . It is further assumed that an AR coating  402  (a film having a function equivalent to the function of the AR coating  271   a  or the anti-reflection treatment portion  291   a  described above) is provided on a surface of the lens  401  into which light enters, and that a protrusion portion  401   a  is provided on an outer peripheral portion of the lens  401 . Note that each of  FIGS. 38 and 39  depicts a configuration of the solid-state imaging element  11 , the glass substrate  12 , and the lens  271  extracted from the integrated configuration unit  10  included in the imaging device  1  of  FIG. 19 . 
     As depicted in  FIG. 39 , the lens  401  here has a mortar shape which has an aspherical recessed shape around the center located at the center of gravity as viewed from the top surface. Note that an upper right part of  FIG. 39  depicts a cross-sectional shape of the lens  401  in a direction indicated by a dotted line in an upper left part of the figure, while a lower right part of the figure depicts a cross-sectional shape of the lens  401  in a direction indicated by a solid line in the upper left part of the figure. 
     In  FIG. 39 , a range Ze of the lens  401  has a common aspherical curved surface structure in both the upper right part and the lower right part of  FIG. 39 . Such a shape constitutes an effective region on the imaging surface of the solid-state imaging element  11  as a region for converging incident light coming from above in the figure. 
     Moreover, a thickness of the lens  401  constituted by the aspherical curved surface varies according to a distance in a direction perpendicular to a light incident direction from the center position. More specifically, the lens thickness becomes a smallest thickness D at the center position and becomes a largest thickness H at a position farthest from the center in the range Ze. In addition, in a case where the thickness of the glass substrate  12  is a thickness Th, the largest thickness H of the lens  401  is larger than the thickness Th of the glass substrate  12 , while the smallest thickness D of the lens  401  is smaller than the thickness Th of the glass substrate  12 . 
     Therefore, to sum up the foregoing relations, (the integrated configuration unit  10 ) of the imaging device  1  which is miniaturized and lightweight and achieves high resolution imaging can be actualized by using the lens  401  and the glass substrate  12  having a relation of “thickness H&gt;thickness Th&gt;thickness D” for the thicknesses D, H, and Th. 
     In addition, the imaging device  1  which is miniaturized and lightweight and achieves high resolution imaging can be actualized by setting a volume VG of the glass substrate  12  to a volume smaller than a volume VL of the lens  401  and thereby achieving highest efficiency of the lens volume. 
     &lt;Stress Distributions Generated During Heating of AR Coating&gt; 
     In addition, the above configuration can reduce stress produced by expansion or contraction of the AR coating  402  during loading of implementation reflow heat or a reliability test. 
       FIG. 40  depicts stress distributions produced by expansion and contraction of the AR coating  402  during loading of implementation reflow heat according to a change of an external shape of the lens  401  of  FIG. 39 . Note that the stress distributions in  FIG. 40  represent distributions in a range of ½ in the horizontal direction and the vertical direction, i.e., ¼ of the whole, with respect to the center position of the lens  401  as a reference, as indicated by the range Zp in  FIG. 38 . 
     A leftmost part of  FIG. 40  depicts a stress distribution produced in AR coating  402 A during loading of implementation reflow heat in a lens  401 A where the protrusion portion  401   a  is not provided. 
     A second part from the left in  FIG. 40  depicts a stress distribution produced in AR coating  402 B during loading of implementation reflow heat in a lens  401 B where the protrusion portion  401   a  depicted in  FIG. 39  is provided. 
     A third part from the left in  FIG. 40  depicts a stress distribution produced in AR coating  402 C during loading of implementation reflow heat in a lens  401 C where the protrusion portion  401   a  depicted in  FIG. 39  has a larger height than that height in  FIG. 39 . 
     A fourth part from the left in  FIG. 40  depicts a stress distribution produced in AR coating  402 D during loading of implementation reflow heat in a lens  401 D where the protrusion portion  401   a  depicted in  FIG. 39  has a larger width than that width in  FIG. 39 . 
     A fifth part from the left in  FIG. 40  depicts a stress distribution produced in AR coating  402 E during loading of implementation reflow heat in a lens  401 E where a side surface of an outer peripheral portion of the protrusion portion  401   a  depicted in  FIG. 39  is more tapered than in  FIG. 39 . 
     A rightmost part of  FIG. 40  depicts a stress distribution produced in AR coating  402 F during loading of implementation reflow heat in a lens  401 F where the protrusion portion  401   a  depicted in  FIG. 39  is provided at only four corners constituting the outer peripheral portion. 
     As depicted in  FIG. 40 , a large stress distribution is exhibited in the outer peripheral side of the effective region in the stress distribution produced in the AR coating  402 A of the lens  401 A where the protrusion portion  401   a  is not provided as depicted in the leftmost part. However, the large stress distribution presented in the AR coating  402 A is not produced in the AR coatings  402 B to  402 F of the lenses  401 B to  401 F on each of which the protrusion portion  401   a  is provided. 
     Accordingly, generation of cracks in the AR coating  402  produced by expansion or contraction of the lens  401  during loading of implementation reflow heat can be reduced by providing the protrusion portion  401   a  on the lens  401 . 
     &lt;Modification of Lens Shape&gt; 
     According to the example described above, the imaging device  1  includes the lens  401  which is recessed and has the protrusion portion  401   a  having the tapered outer peripheral portion as depicted in  FIG. 39  to achieve miniaturization, weight reduction, and high-resolution imaging. However, the lens  401  may have other shapes as long as the lens  401  and the glass substrate  12  have the relation “thickness H&gt;thickness Th&gt;thickness D” for the thicknesses D, H, and Th. Moreover, it is more preferable that a relation “volume VG&lt;volume VL” holds for the volumes VG and VL. 
     For example, as depicted in a lens  401 G of  FIG. 41 , the side surface on the outer peripheral side of the protrusion portion  401   a  may have a right angle with respect to the glass substrate  12  without including a taper. 
     Further, as depicted in a lens  401 H of  FIG. 41 , the side surface on the outer peripheral side of the protrusion portion  401   a  may include a round taper. 
     Further, as depicted in a lens  401 I of  FIG. 41 , the side surface may include a linear tapered shape having a predetermined angle with respect to the glass substrate  12  without including the protrusion portion  401   a  itself. 
     Further, as depicted in a lens  401 I of  FIG. 41 , the side surface may have a configuration not including the protrusion portion  401   a  itself, i.e., may have a configuration forming a right angle with respect to the glass substrate  12  without including a tapered shape. 
     Further, as depicted in a lens  401 K of  FIG. 41 , the side surface may include a round tapered shape with respect to the glass substrate  12  without including the protrusion portion  401   a  itself. 
     Further, as depicted in a lens  401 L of  FIG. 41 , the side surface of the lens may have a two-stage configuration having two inflection points without including the protrusion portion  401   a  itself. Note that a detailed configuration of the lens  401 L will be described below with reference to  FIG. 42 . In addition, the side surface of the lens  401 L has a two-stage configuration having two inflection points, and therefore will be also referred to as a two-stage side surface lens. 
     Further, as depicted in a lens  401 M of  FIG. 41 , the side surface may include the protrusion portion  401   a  and also have a two-stage configuration having two inflection points in the external shape side surface. 
     Further, as depicted in a lens  401 N of  FIG. 41 , the side surface may include the protrusion portion  401   a  and may further have a hemming bottom portion  401   b  having a square shape in the vicinity of the boundary with the glass substrate  12  as a configuration having a right angle with respect to the glass substrate  12 . 
     Moreover, as depicted in the lens  401 N of  FIG. 41 , the protrusion portion  401   a  may be included, and a hemming bottom portion  401   b ′ having a round shape may be further added to the vicinity of the boundary with the glass substrate  12  as a configuration having a right angle with respect to the glass substrate  12 . 
     &lt;Detailed Configuration of Two-Stage Side Surface Lens&gt; 
     A detailed configuration of the two-stage side surface lens  401 L of  FIG. 41  will be here described with reference to  FIG. 42 . 
       FIG. 42  is an external appearance perspective view as viewed in various directions when the two-stage side surface lens  401 L is provided on the glass substrate  12  formed on the solid-state imaging element  11 . In an upper center part of  FIG. 42 , sides LA, LB, LC, and LD are here defined clockwise from a right side of the solid-state imaging element  11  in this order in the figure. 
     In addition, a right part of  FIG. 42  is a perspective view around a corner formed by the sides LA and LB of the solid-state imaging element  11  when the solid-state imaging element  11  and the lens  401 L are viewed in a visual line E 1  in the upper center part of  FIG. 42 . Moreover, a lower center part of  FIG. 42  is a perspective view around the corner formed by the sides LA and LB of the solid-state imaging element  11  when the solid-state imaging element  11  and the lens  401 L are viewed in a visual line E 2  in the upper center part of  FIG. 42 . Furthermore, a lower left part of  FIG. 42  is a perspective view around a corner formed by the sides LB and LC of the solid-state imaging element  11  when the solid-state imaging element  11  and the lens  401 L are viewed in a visual line E 3  in the center part of  FIG. 42 . 
     Specifically, according to the two-stage side surface lens  401 L, each of center portions of the sides LB and LD (not depicted) corresponding to longer sides is located close to a center of gravity having a smallest lens thickness in a circle functioning as a lens as viewed from a top surface of the two-stage side surface lens  401 L corresponding to a recessed lens. Accordingly, the lens becomes thin, and each of ridges has a shape of a gradual curve as surrounded by a dotted line. 
     On the other hand, each of center portions of the sides LA and LC corresponding to short sides is located far from the center of gravity. In this case, the lens becomes thick, and each of ridges each has a linear shape. 
     &lt;Two Inflection Points and Two-Stage Side Surface&gt; 
     In addition, as depicted in  FIG. 43 , according to the two-stage side surface lens  401 L, a side surface in a non-effective region provided outside an effective region Ze has a two-stage configuration in a cross-sectional shape. Average surfaces X 1  and X 2  of the side surface deviate from each other. Inflection points P 1  and P 2  in the cross-sectional shape are formed at positions where a step is produced by two-stage side surface. 
     The inflection points P 1  and P 2  are points of recessed and projected changes in this order from a position near the solid-state imaging element  11 . 
     In addition, each of the inflection points P 1  and P 2  from the glass substrate  12  is located at a position higher than the smallest thickness Th of the two-stage side surface lens  401 L. 
     Further, a difference between the respective average surfaces X 1  and X 2  (a distance between the average surfaces X 1  and X 2 ) of the two-stage side surface is preferably larger than the thickness of the solid-state imaging element  11  (the thickness of the silicon substrate  81  of the solid-state imaging element  11  of  FIG. 6 ). 
     Further, the distance difference between the average surfaces X 1  and X 2  of the two-stage side surface is preferably is 1% or more of a region width perpendicular to an incident direction of incident light in the effective region of the lens  401 L (for example, a width He in the horizontal direction or a height Ve in the vertical direction in  FIG. 23 ). 
     Accordingly, a shape other than the shape of the two-stage side surface lens  401 L may be adopted as long as the two-stage side surface and the two inflection points meeting the foregoing conditions are formed. For example, as depicted in a second part from above in  FIG. 43 , the two-stage side surface lens may be a two-stage side surface lens  401 P which includes a two-stage side surface constituted by average surfaces X 11  and X 12 , and has inflection points P 11  and P 12  having curvatures different from those of the inflection points P 1  and P 2  and located at positions higher than the smallest thickness Th of the lens from the glass substrate  12 . 
     Moreover, for example, as depicted in a third part from above in  FIG. 43 , the two-stage side surface lens may be a two-stage side surface lens  401 Q which includes a two-stage side surface constituted by average surfaces X 21  and X 22 , and has inflection points P 21  and P 22  having curvatures different from those of the inflection points P 1  and P 2  and the inflection points P 11  and P 22 , and located at positions higher than the smallest thickness Th of the lens from the glass substrate  12 . 
     Furthermore, for example, as depicted in a fourth part from above in  FIG. 43 , the two-stage side surface lens may be a two-stage side surface lens  401 R which includes a two-stage side surface constituted by average surfaces X 31  and X 32 , has inflection points P 31  and P 32  located at positions higher than the smallest thickness Th of the lens from the glass substrate  12 , and has a round end portion located at a thickest position of the lens  401 . 
     &lt;Stress Distributions Generated During Heating of AR Coating in Lens Including Side Surface Having Two Inflection Points and Two-Stage Configuration&gt; 
     As described above, the two-stage side surface lens  401 L which has two inflection points and a side surface having a two-stage configuration can reduce stress applied to the AR coating  402  by expansion or contraction of the lens  401 L during loading of implementation reflow heat or a reliability test. 
       FIG. 44  depicts stress distributions produced by expansion and contraction of the AR coating  402  during loading of implementation reflow heat according to a change of the external shape of the lens  401  of  FIG. 39 . In  FIG. 44 , an upper part depicts stress distributions of the AR coating  402  on the back side when the lens  401  is viewed in a diagonal direction. A lower part of the figure depicts stress distributions of the AR coating  402  on the front side when the lens  401  is viewed in the diagonal direction. 
     A leftmost part of  FIG. 44  depicts a stress distribution produced in an AR coating  402 S during loading of implementation reflow heat in a lens  401 S (corresponding to the lens  401 A) which does not have the protrusion portion  401   a  and is not a two-stage side surface lens. 
     A second part from the left in  FIG. 44  depicts a stress distribution produced in AR coating  402 T during loading of implementation reflow heat in a lens  401 T corresponding to the two-stage side surface lens  401 L depicted in  FIG. 43 . 
     A third part from the left in  FIG. 44  depicts a stress distribution produced in AR coating  402 U during loading of implementation reflow heat in a lens  401 U which does not include the protrusion portion  401   a , but has a tapered portion and round-molded corners of respective sides of the lens. 
     A fourth part from the left in  FIG. 44  depicts a stress distribution produced in AR coating  402 V during loading of implementation reflow heat in a lens  401 V which does not include the protrusion portion  401   a  nor a tapered portion, but has a side surface perpendicular to the glass substrate  12 , and round-molded corners of respective sides of the lens. 
     In addition,  FIG. 45  presents graphs of maximum values in respective areas in the stress distributions produced in the AR coating in the respective lens shapes of  FIG. 44 , i.e., maximum values in the whole (Worst), maximum values in the effective region of the lens (effective), and maximum values in a ridge (ridge) in this order from the left of the figure. Further, the graphs of the maximum values in each of the areas in  FIG. 45  indicate maximum values in stress distributions of the AR coating  402 S to  402 V in this order from the left. 
       FIG. 45  presents the maximum stress exhibited in the whole of each of the lenses. Specifically, the maximum stress becomes 1390 MPa at a corner Ws of a top surface ( FIG. 44 ) in the case of the AR coating  402 S of the lens  401 S, becomes 1130 MPa at a corner Wt in a ridge ( FIG. 44 ) in the case of the AR coating  402 T of the lens  401 T, becomes 800 MPa on a ridge Wu ( FIG. 44 ) in the case of the AR coating  402 U of the lens  401 U, and becomes 1230 MPa on a ridge Wv ( FIG. 44 ) in the case of the AR coating  402 V of the lens  401 V. 
     In addition,  FIG. 45  presents the maximum stress exhibited in the effective region of each of the lenses. Specifically, the maximum stress becomes 646 MPa in the case of the AR coating  402 S of the lens  401 S, becomes 588 MPa in the case of the AR coating  402 T of the lens  401 T, becomes 690 MPa in the case of the AR coating  402 U of the lens  401 U, and becomes 656 MPa in the case of the AR coating  402 V of the lens  401 V. 
     Moreover, in the ridge of each of the lenses, the maximum stress becomes 1050 MPa in the case of the AR coating  402 S of the lens  401 S, becomes 950 MPa in the case of the AR coating  402 T of the lens  401 T, becomes 800 MPa in the case of the AR coating  402 U of the lens  401 U, and becomes 1230 MPa in the case of the AR coating  402 U of the lens  401 V. 
     According to  FIG. 45 , the maximum stress becomes the minimum in the case of the AR coating  402 S of the lens  401 S in each of the areas. As apparent from  FIG. 44 , the stress distribution around 600 Mpa increases in a range close to the outer peripheral portion of the AR coating  402 U of the lens  401 U, but does not exist in the stress distribution in the whole effective region of the AR coating  402 T of the lens  401 T. As a whole, the stress distribution produced in the AR coating  402 T of the AR coating  402 T (identical to the AR coating  402 L) decreases in the external shape constituted by the AR coating  402 T of the lens  401 T (identical to the lens  401 L). 
     In other words, as apparent from  FIGS. 44 and 45 , expansion and contraction caused in the AR coating  402 T ( 402 L) is reduced in the lens  401 T ( 401 L) which has the two inflection points and the side surface having the two-stage configuration during loading of implementation reflow heat. Accordingly, stress produced by expansion or contraction decreases. 
     As described above, the two-stage side surface lens  401 L which has the two inflection points and the side surface having the two-stage configuration is adopted as the lens  401 . Accordingly, expansion or contraction caused by heat can be reduced during loading of implementation reflow heat, a reliability test, or the like. 
     As a result, stress applied to the AR coating  402 L can be lowered. Accordingly, reduction of generation of cracks and reduction of generation of lens separation or the like are achievable. In addition, reduction of expansion or contraction of the lens itself thus achieved can reduce generation of distortion, and, therefore, reduction of image quality deterioration according to an increase in double refraction caused by distortion and reduction of a flare generated according to an increase in interface reflection caused by a local change of a refractive index are achievable. 
     18. Eighteenth Embodiment 
     According to the example described above, a lens which is miniaturized and lightweight and achieves high-resolution imaging is actualized by specifying the lens shape. However, a lens which is more miniaturized and lightweight and achieves high-resolution imaging may be actualized by increasing accuracy during formation of the lens on the solid-state imaging element  11 . 
     As depicted in an upper part of  FIG. 46 , ultraviolet curing resin  461  as a material of the lens  401  is filled into a space formed between a mold  452  and the glass substrate  12  in a state where the mold  452  on a substrate  451  is pressed against the glass substrate  12  on the solid-state imaging element  11 . Thereafter, exposure to ultraviolet light is carried out for a predetermined time from an upper part of the figure. 
     Each of the substrate  451  and the mold  452  is made of material transmitting ultraviolet light. 
     The mold  452  has an aspherical projected structure corresponding to the shape of the lens  401  of a recessed type. A light shielding film  453  is formed in an outer peripheral portion of the mold  452 . For example, the mold  452  is capable of forming a taper having an angle θ in the side surface of the lens  401  as depicted in  FIG. 46  according to an incident angle of ultraviolet light. 
     The ultraviolet curing resin  461  as a material of the lens  401  is cured by exposure to ultraviolet light for a predetermined time. The cured ultraviolet curing resin  461  is formed as an aspherical recessed lens and affixed to the glass substrate  12  as depicted in a lower part of  FIG. 46 . 
     After an elapse of the predetermined time in the state of irradiation with ultraviolet light, the ultraviolet curing resin  461  is cured and forms the lens  401 . After formation of the lens  401 , the mold  452  is separated from the lens  401  thus formed (mold separation). 
     A part of the ultraviolet curing resin  461  leaks from the mold  452  and forms a leak portion  461   a  at the boundary between the outer peripheral portion of the lens  401  and the glass substrate  12 . However, the leak portion  461   a  is shielded from ultraviolet light by the light shielding film  453 . Accordingly, as indicated by a range Zc in an enlarged diagram Zf, the leak portion  461   a  as a part of the ultraviolet curing resin  461  remains uncured, and is cured by ultraviolet light contained in natural light after mold separation. As a result, the leak portion  461   a  remains as a hemming bottom portion  401   d.    
     In this manner, the lens  401  is formed into a recessed lens using the mold  452 , and a taper shape having the angle θ specified by the light shielding film  453  is formed in the side surface of the lens  401 . Further, the hemming bottom portion  401   d  is formed in the outer peripheral portion of the lens  401  at the boundary with the glass substrate  12 . In this case, the lens  401  can be bonded to the glass substrate  12  with more rigidity. 
     As a result, a lens which is miniaturized and lightweight and achieves high-resolution imaging can be produced with high accuracy. 
     Note that the example described above is the case where the light shielding film  453  is provided on the substrate  451  in the outer peripheral portion of the lens  401  on the back side (lower side in the figure) of the substrate  451  with respect to the incident direction of the ultraviolet light as depicted in an upper left part of  FIG. 47 . However, the light shielding film  453  may be provided on the substrate  451  in the outer peripheral portion of the lens  401  on the front side (upper side in the figure) of the substrate  451  with respect to the incident direction of the ultraviolet light as depicted in an upper right part of  FIG. 47 . 
     Further, a mold  452 ′ larger in the horizontal direction than the mold  452  may be formed, and the light shielding film  453  may be provided on the outer peripheral portion of the lens  401  instead of the substrate  451  on the back side (lower side in the figure) with respect to the incident direction of the ultraviolet light as depicted in a left and second part from above in  FIG. 47 . 
     Further, the light shielding film  453  may be provided on the substrate  451  on the mold  452 ′ in the outer peripheral portion of the lens  401  on the front side (upper side in the figure) of the substrate  451  with respect to the incident direction of the ultraviolet light as depicted in a right and second part from above in  FIG. 47 . 
     Further, a mold  452 ″ may be produced by integrating the substrate  451  and the mold  452 , and the light shielding film  453  may be provided in the outer peripheral portion of the lens  401  on the back side (lower side in the figure) with respect to the incident direction of the ultraviolet light as depicted in a left and third part from above in  FIG. 47 . 
     Moreover, the mold  452 ″ may be produced by integrating the substrate  451  and the mold  452 , and the light shielding film  453  may be provided in the outer peripheral portion of the lens  401  on the front side (upper side in the figure) with respect to the incident direction of the ultraviolet light as depicted in a right and third part from above in  FIG. 47 . 
     Furthermore, a mold  452 ′″ which has a configuration for regulating a part of the side surface portion may be formed in addition to the substrate  451  and the mold  452 , and the light shielding film  453  may be provided in the outer peripheral portion of the mold  452 ′″ and on the back side with respect to the incident direction of the ultraviolet light as depicted in a left lower part of  FIG. 47 . 
     Note that each of the configurations of  FIGS. 46 and 47  is a configuration where the IRCF  14  and the adhesive  15  are eliminated from the integrated configuration unit  10  of the imaging device  1  of  FIG. 9 . However, this elimination is made only for convenience of explanation. Needless to say, the IRCF  14  and the adhesive  15  may be provided between the lens  401  ( 131 ) and the glass substrate  12 . Furthermore, the description of the example continues hereinafter on an assumption that the IRCF  14  and the adhesive  15  are omitted from the configuration of the imaging device  1  depicted in  FIG. 9 . In any cases, however, the IRCF  14  and the adhesive  15  may be provided between the lens  401  ( 131 ) and the glass substrate  12 , for example. 
     &lt;Forming Method of Two-Stage Side Surface Lens&gt; 
     A manufacturing method of the two-stage side surface lens will be subsequently described. 
     A basic manufacturing method is similar to the manufacturing method for a lens of not the two-stage side surface type described above. 
     Specifically, as depicted in a left part of  FIG. 48 , the mold  452  corresponding to the side surface shape of the two-stage side surface lens  401 L is prepared for the substrate  451 . The ultraviolet curing resin  461  is placed on the glass substrate  12  provided on the solid-state imaging element  11 . Note that  FIG. 48  depicts a configuration of only a right half of a side cross section of the mold  452 . 
     Subsequently, as depicted in a center part of  FIG. 48 , the ultraviolet curing resin  461  on which the mold  452  is placed is fixed with a press against the glass substrate  12 . In this state, ultraviolet light is applied from above in the figure with the ultraviolet curing resin  461  filled into a recess of the mold  452 . 
     The ultraviolet curing resin  461  is cured by exposure to the ultraviolet light. As a result, the two-stage side surface lens  401  having a recessed shape corresponding to the mold  452  is formed. 
     After the lens  401  is formed by exposure to the ultraviolet light for the predetermined time, the mold  452  is separated from the mold as depicted in a right part of  FIG. 48 . As a result, the lens  401  constituted by the two-stage side surface lens is completed. 
     In addition, as depicted in a left part of  FIG. 49 , a part of an outer peripheral portion of the mold  452  in a portion in contact with the glass substrate  12 , i.e., a portion below the height of the inflection point located close to the glass substrate  12  in the two inflection points of the cross-sectional shape of the side surface, for example, may be cut to provide the light shielding film  453  on a cut surface. 
     In this case, as depicted in a second part from the left in  FIG. 49 , the ultraviolet light is shielded in a portion below the light shielding film  453  when the ultraviolet light is applied for a predetermined time from above in the figure in a state where the ultraviolet curing resin  461  is filled into the recess of the mold  452 . In this case, curing does not progress in that portion, and the lens  401  remains uncompleted. However, the ultraviolet curing resin  461  which is located around the effective region in the figure and exposed to the ultraviolet light is cured and constitutes the lens  401 . 
     When the mold  452  is separated in this state, a side surface of the two-stage configuration in a portion close to the glass substrate  12  in an outermost periphery of the lens  401  constituted as the two-stage side surface lens is left as the leak portion  461   a  of the uncured ultraviolet curing resin  461  as depicted in a third part from the left in  FIG. 49 . 
     Accordingly, as depicted in a right part of  FIG. 49 , ultraviolet light is separately applied to the side surface still in the state of the leak portion  461   a  of the uncured ultraviolet curing resin  461  to cure the side surface while controlling an angle and surface roughness of the side surface. 
     In such a manner, as depicted in an upper part of  FIG. 50 , angles formed by average surfaces X 1  and X 2  of the side surface of the lens  401  are allowed to be set to different angles, such as angles θ 1  and θ 2 , with respect to the incident direction of the incident light. 
     When the angles of the side surfaces X 1  and X 2  here are set as angle θ 1 &lt;angle θ 2  on an assumption that the angles of the side surfaces X 1  and X 2  are angles θ 1  and θ 2 , respectively, generation of a side surface flare and separation of the completed lens  401  from the glass substrate  12  during mold separation of the mold  452  can be reduced. 
     In addition, surface roughness values ρ(X 1 ) and ρ(X 2 ) of the side surfaces X 1  and X 2 , respectively, are allowed to be set to different values. 
     When the respective surface roughness values ρ(X 1 ) and ρ(X 2 ) of the side surfaces X 1  and X 2  here are set as the surface roughness ρ(X 1 )&lt;the surface roughness ρ(X 2 ), generation of a side surface flare and separation of the completed lens  401  from the glass substrate  12  during mold separation of the mold  452  can be reduced. 
     Moreover, the hemming bottom portion  401   d  can be formed by adjusting the shape of the leak portion  461   a  of the ultraviolet curing resin  461  as depicted in a lower part of  FIG. 50 . In this manner, the lens  401  can be more rigidly fixed to the glass substrate  12 . 
     Note that formation of the angles θ 1  and θ 2 , the surface roughness values ρ(X 1 ) and ρ(X 2 ), and the hemming bottom portion  401   d  can be defined using the shape of the mold  452  even in a case where the light shielding film  453  described with reference to  FIG. 48  is not adopted. However, in a case where the mold  452  equipped with the light shielding film  453  is used as described with reference to  FIG. 49 , later adjustment is allowed for the leak portion  461   a  of the ultraviolet curing resin  461  left as an uncured portion after initial irradiation of ultraviolet light. Accordingly, the degree of setting freedom of the angles θ 1  and θ 2 , the surface roughness values ρ(X 1 ) and ρ(X 2 ), and the hemming bottom portion  401   d  can be raised. 
     In either of the cases, the lens  401  can be accurately provided on the glass substrate  12  formed on the solid-state imaging element  11 . Further, the angles of the side surfaces X 1  and X 2 , the surface roughness values ρ(X 1 ) and ρ(X 2 ), and the presence or absence of the hemming bottom portion  401   d  of the two-stage side surface lens  401  are adjustable. Accordingly, generation of a flare or a ghost can be reduced, and also the lens  401  can be more rigidly provided on the glass substrate  12 . 
     19. Nineteenth Embodiment 
     According to the example described above, the lens  401  is accurately provided on the glass substrate  12  formed on the solid-state imaging element  11  by using the molding method. However, an alignment mark may be formed on the glass substrate  12  to provide the lens  401  at an appropriate position on the glass substrate  12 . In this manner, the lens  401  may be positioned on the basis of the alignment mark to more accurately provide the lens  401  on the glass substrate  12 . 
     Specifically, as depicted in  FIG. 51 , the effective region Ze of the lens  401  (corresponding to the effective region  131   a  of  FIG. 23 ) is defined from the center. A non-effective region Zn (corresponding to the non-effective region  131   b  of  FIG. 23 ) is provided in the outer peripheral portion of the lens  401 . A region Zg to which the glass substrate  12  is exposed is provided in the further outer peripheral portion. A region Zsc where a scribe line is defined is provided in the outermost peripheral portion of the solid-state imaging element  11 . In  FIG. 51 , a protrusion portion  401   a  is provided in the non-effective region Zn (corresponding to the non-effective region  131   b  of  FIG. 23 ). 
     The respective regions have a width relation of “the width of the effective region Ze&gt;the width of the non-effective region Zn&gt;the width of the region Zg to which the glass substrate  12  is exposed&gt;the width of the region Zsc where the scribe line is defined.” 
     An alignment mark  501  is formed in the region Zg on the glass substrate  12  as a region to which the glass substrate  12  is exposed. Accordingly, the size of the alignment mark  501  is smaller than the size of the region Zg, but is required to be a size sufficient for recognizing an image of the alignment mark  501  for alignment. 
     For example, alignment may be achieved by forming the alignment mark  501  on the glass substrate  12  at a position to be in contact with the corner of the lens  401 , and adjusting the corner of the lens in the mold  452  to a position aligned with the position where the alignment mark  501  is formed on the basis of an image captured by an alignment camera. 
     &lt;Example of Alignment Mark&gt; 
     For example, alignment marks  501 A to  501 K depicted in  FIG. 52  may be adopted as the alignment mark  501 . 
     Specifically, each of the alignment marks  501 A to  501 C has a square shape, each of the alignment marks  501 D and  501 E has a circular shape, each of the alignment marks  501 F to  5011  has a polygonal shape, and each of the alignment marks  5011  and  501 K is constituted by a plurality of linear shapes. 
     &lt;Examples of Alignment Mark Formed on Glass Substrate and Mold&gt; 
     In addition, positions of the lens  401  and the glass substrate  12  may be aligned by forming a black portion and a gray portion of each of the alignment marks  501 A to  501 K at positions corresponding to the outer peripheral portion of the lens  401  on the mold  452  and the region Zg on the glass substrate  12 , respectively, and checking whether a positional relation of mutual correspondence has been achieved on the basis of an image captured by an alignment camera, for example. 
     Specifically, in a case of the alignment mark  501 A, as depicted in  FIG. 52 , an alignment mark  501 ′ for the gray portion constituted by a square frame is formed on the mold  452 , while the alignment mark  501  constituted by a square portion as the black portion is formed. Both the alignment marks  501 ′ and  501  are formed such that an appropriate positional relation between the lens  401  and the mold  452  holds. 
     Thereafter, alignment may be adjusted by capturing an image of the alignment mark  501  on the glass substrate  12  and an image of the alignment mark  501 ′ on the mold  452  in an arrow direction of  FIG. 53  using the alignment camera, and adjusting the position of the mold  452  such that an image of the alignment mark  501  having a black direction shape and overlapped within the alignment mark  501 ′ constituted by a gray square frame is captured. 
     In this case, it is preferable that the alignment mark  501  as the black portion and the alignment mark  501 ′ as the gray portion are arranged within an identical visual field of an identical camera. However, alignment may be achieved by calibrating a positional relation between a plurality of cameras beforehand, and adjusting the correspondence of the positional relation between the alignment marks  501  and  501 ′ provided at corresponding different positions using the plurality of cameras. 
     In either of the cases, the lens  401  can be accurately positioned and provided on the glass substrate  12  formed on the solid-state imaging element  11  by using the alignment mark  501 . 
     20. Twentieth Embodiment 
     According to the example described above, the lens  401  and the glass substrate  12  on the solid-state imaging element  11  are accurately positioned and provided by using the alignment mark. However, the AR coating  402  may be formed in the effective region of the lens  401  to increase sensitivity and achieve fine imaging. 
     Specifically, for example, an AR coating  402 -P 1  may be formed on an entire area of the glass substrate  12 , in the non-effective region containing a side surface and a flat surface portion of the protrusion portion  401   a  (corresponding to the non-effective region  131   b  of  FIG. 23 ) and the effective region (corresponding to the effective region  131   a  of  FIG. 23 ) as indicated by a thick line in an uppermost part of  FIG. 54 . 
     Moreover, for example, an AR coating  402 -P 2  may be formed in only the effective region within the protrusion portion  401   a  on the lens  401  as depicted in a second part from above in  FIG. 54 . By forming the AR coating  402 -P 2  in only the region within the protrusion portion  401   a  on the lens  401  (effective region (corresponding to the effective region  131   a  of  FIG. 23 )), stress produced by expansion or contraction of the lens  401  by heat during loading of implementation reflow heat or the like can be reduced, and therefore generation of cracks in the AR coating  402 -P 2  can be reduced. 
     Additionally, for example, an AR coating  402 -P 3  may be formed in a region which is located inside the protrusion portion  401   a  (effective region (corresponding to the effective region  131   a  of  FIG. 23 )) and includes the flat surface portion of the protrusion portion  401   a  on the lens  401  as depicted in a third part from above in  FIG. 54 . By forming the AR coating  402 -P 3  in only the region which is located inside the protrusion portion  401   a  and includes the protrusion portion  401   a  on the lens  401 , stress produced for the AR coating  402 -P 3  by expansion or contraction of the lens  401  by heat during loading of implementation reflow heat or the like can be reduced, and therefore generation of cracks can be reduced. 
     Furthermore, for example, an AR coating  402 -P 4  may be formed in a region inside the protrusion portion  401   a  (effective region (corresponding to the effective region  131   a  of  FIG. 23 )) in addition to the flat surface portion of the protrusion portion  401   a  on the lens  401  and a part of the outer peripheral portion of the flat surface portion, and an AR coating  402 -P 5  may be further formed on the glass substrate  12  and in a region on the lens  401  in the vicinity of the boundary with the glass substrate  12  as depicted in a fourth part from above in  FIG. 54 . As that in the case of the AR coatings  402 -P 4  and  402 -P 5 , a region where the AR coating is not formed is defined in a part of the side surface portion of the lens  401 . In this manner, stress produced for the AR coating  402 -P 2  by expansion or contraction of the lens  401  by heat during loading of implementation reflow heat or the like can be reduced, and therefore generation of cracks can be reduced. 
       FIG. 55  collectively presents stress distributions produced in the AR coating  402  during loading of implementation reflow heat with various changes in the region where the AR coating  402  is formed in the lens  401 . 
     An upper part of  FIG. 55  depicts external shapes of the lens  401  and the AR coating  402  when the lens  401  is divided into two parts in both the horizontal and vertical directions, while a lower part depicts distributions of stress produced in the corresponding AR coating  402  during loading of implementation reflow heat. 
     A left part of  FIG. 55  depicts a case of formation of an AR coating  402 AA where an AR coating is formed in an entire area including the glass substrate  12  in the periphery, the side surface of the lens  401 , the protrusion portion  401   a , and the inside of the protrusion portion  401   a.    
     A second part from the left in  FIG. 55  depicts a case of an AR coating  402 AB where an AR coating is not formed in the glass substrate  12  in the periphery and the side surface of the lens  401 , and is formed in other regions in the configuration of the leftmost part of  FIG. 55 . 
     A third part from the left in  FIG. 55  depicts a case of an AR coating  402 AC where an AR coating is not formed in the region of the side surface of the lens  401 , and is formed in the glass substrate  12  in the periphery, the protrusion portion  401   a , and the inside of the protrusion portion  401   a  in the configuration of the leftmost part of  FIG. 55 . 
     A fourth part from the left in  FIG. 55  depicts a case of an AR coating  402 AD where an AR coating is not formed in the region of the side surface of the lens  401 , the flat surface portion of the protrusion portion  401   a , and a region inside the protrusion portion  401   a  in a range of a predetermined width A from a flattened portion of the top surface of the protrusion portion  401   a , and is formed inside the other range of the protrusion portion  401   a  and the glass substrate  12  in the periphery in the configuration of the leftmost part of  FIG. 55 . The width A here is 100 μm, for example. 
     A fifth part from the left in  FIG. 55  depicts a case of an AR coating  402 AE where an AR coating is formed in the inside of the protrusion portion  401   a , the flattened portion of the top surface of the protrusion portion  401   a , and a range of the predetermined width A below the flattened portion in the side surface outside the protrusion portion  401   a  in the configuration of the leftmost part of  FIG. 55 . 
     A sixth part from the left in  FIG. 55  depicts a case of an AR coating  402 AF where an AR coating is formed in the inside of the protrusion portion  401   a , the flattened portion of the top surface of the protrusion portion  401   a , and a range of a predetermined width  2 A below the flattened portion in the side surface outside the protrusion portion  401   a  in the configuration of the leftmost part of  FIG. 55 . 
     A seventh part from the left in  FIG. 55  depicts a case of an AR coating  402 AG where an AR coating is formed in the inside of the protrusion portion  401   a , the flattened portion of the top surface of the protrusion portion  401   a , and a range of a predetermined width  3 A below the flattened portion in the side surface outside the protrusion portion  401   a  in the configuration of the leftmost part of  FIG. 55 . 
     An eighth part from the left in  FIG. 55  depicts a case of an AR coating  402 AH where an AR coating is formed in the inside of the protrusion portion  401   a , the flattened portion of the top surface of the protrusion portion  401   a , and a range of a predetermined width  4 A below the flattened portion in the side surface outside the protrusion portion  401   a  in the configuration of the leftmost part of  FIG. 55 . 
     As indicated by a comparison with the leftmost part of  FIG. 55 , stress produced in the AR coating  402  in any of the cases becomes smaller in the AR coating  402  formed such that the AR coating inside the protrusion portion  401   a  on the lens  401  is not continuously connected to the AR coating  402  on the glass substrate  12  than in the AR coating  402 AA where the AR coating  402  is formed to cover the entire surface of the lens  401 . 
     Generation of a flare or a ghost can be reduced by forming the AR coating  402  on the lens  401  in the manner described above. Accordingly, finer imaging is achievable. 
     Moreover, generation of cracks caused by expansion or contraction by heating during loading of implementation reflow heat, a reliability test or the like can be reduced by providing the AR coating  402  in such a manner as to leave a region where the AR coating is not formed in the effective region and at least a part other than the glass substrate  12  on the entire surface including the effective region and the non-effective region in the lens  401  including the protrusion portion  401   a  and the glass substrate  12  as the outer peripheral portion of the lens  401 . 
     While the AR coating  402  has been described above, other films may be adopted as long as the films are formed on the surface of the lens  401 . For example, an anti-reflection film such as a moth eye film may be adopted. 
     Furthermore, while the example of the lens including the protrusion portion  401   a  has been described above, it is sufficient if a lens not including the protrusion portion  401   a  is adopted as long as the region where the AR coating is not formed is provided in the effective region and at least a part other than the glass substrate  12  on the entire surface including the effective region and the non-effective region and the glass substrate  12  as the outer peripheral portion of the lens  401 . In other words, it is sufficient if the AR coating  402  formed on the lens  401  is not provided in a state continuously connected to the AR coating  402  provided on the lens side surface and the glass substrate  12 . Accordingly, the lens  401  may be the two-stage side surface lens  401 L, for example. In this case, similar effects can be produced if the AR coating  402  is formed on the lens  401  in such a manner as not to be provided in a state continuously connected to the AR coating  402  provided on the lens side surface and the glass substrate  12 . 
     21. Twenty-First Embodiment 
     According to the example described above, stress produced in the AR coating  402  by expansion or contraction by heat during loading of implementation reflow heat is reduced by forming the AR coating  402  on the lens  401  in such a state not continuously connected to the AR coating  402  provided on the glass substrate  12 . 
     However, generation of a side surface flare may be reduced by forming a light shielding film in such a manner as to cover the protrusion portion  401   a  and the side surface of the lens  401 . 
     Specifically, as depicted in an uppermost part of  FIG. 56 , a light shielding film  521  may be formed in an entire range including the side surface of the lens  401  and an area up to the height of the flat surface portion of the top surface of the protrusion portion  401   a , i.e., a range other than the effective region on the glass substrate  12 . 
     Further, as depicted in a second part from above in  FIG. 56 , the light shielding film  521  may be formed in a range of the upper part of the glass substrate  12  to the side surface of the lens  401 , and an entire surface up to the flat surface portion of the top surface of the protrusion portion  401   a , i.e., the entire area of the surface portion other than the effective region. 
     Further, as depicted in a third part from above in  FIG. 56 , the light shielding film  521  may be formed in a range of the upper part of the glass substrate  12  to the side surface of the protrusion portion  401   a  of the lens  401 . 
     Further, as depicted in a fourth part from above in  FIG. 56 , the light shielding film  521  may be formed in a range of the upper part of the glass substrate  12  up to a predetermined height from the glass substrate  12  on the side surface of the protrusion portion  401   a  of the lens  401 . 
     Further, as depicted in a fifth part from above in  FIG. 56 , the light shielding film  521  may be formed on only the side surface of the protrusion portion  401   a  of the lens  401 . 
     Further, as depicted in a sixth part from above in  FIG. 56 , the light shielding film  521  may be formed in a range up to highest positions of the two side surfaces of the two-stage side surface lens  401  on the glass substrate  12 . 
     Further, as depicted in a seventh part from above in  FIG. 56 , the light shielding film  521  may be formed in such a manner as to cover the entire surface up to the highest positions of the two side surfaces of the two-stage side surface lens  401  on the glass substrate  12  and the outer peripheral portion of the solid-state imaging element  11 . 
     In any of these cases, the light shielding film  521  is formed by partial film forming, by lithography after film forming, by forming resist, forming a film, and then lifting off the resist, or by lithography. 
     Further, a bank for forming a light shielding film may be provided in the outer peripheral portion of the two-stage side surface lens  401 , and then the light shielding film  521  may be formed inside the bank and in the outer peripheral portion of the two-stage side surface lens  401 . 
     Specifically, as depicted in an uppermost part of  FIG. 57 , a bank  531  at a height equivalent to a lens height may be formed on the glass substrate  12  in the outer peripheral portion of the two-stage side surface lens  401 . In this case, the light shielding film  521  may be formed inside the bank  531  and in the outer peripheral portion of the two-stage side surface lens  401  by lithography or coating, and then the heights of the light shielding film  521 , the lens  401 , and the bank  531  may be equalized by polishing such as CMP (Chemical Mechanical Polishing). 
     Further, as depicted in a second part of  FIG. 57 , the bank  531  at a height equivalent to a lens height may be formed on the glass substrate  12  in the outer peripheral portion of the two-stage side surface lens  401 . In this case, a material of the light shielding film  521  may be only applied to the inside of the bank  531  and in the outer peripheral portion of the two-stage side surface lens  401 , and the heights of the light shielding film  521 , the lens  401 , and the bank  531  may be self-aligned based on the material of the light shielding film  521 . 
     Further, as depicted in a third part of  FIG. 57 , the bank  531  at a height equivalent to a lens height may be formed on the glass substrate  12  in the outer peripheral portion of the two-stage side surface lens  401 . In this case, the light shielding film  521  may be only formed inside the bank  531  and in the outer peripheral portion of the two-stage side surface lens  401  by lithography. 
     Further, as depicted in a fourth part of  FIG. 57 , the bank  531  may be formed on the glass substrate  12  in the outer peripheral portion of the two-stage side surface lens  401  in such a manner as to connect the boundary between the two-stage side surface lens  401  and the glass substrate  12 . In this case, the light shielding film  521  may be formed inside the bank  531  and in the outer peripheral portion of the two-stage side surface lens  401  by lithography or coating, and then the heights of the light shielding film  521 , the lens  401 , and the bank  531  may be equalized by polishing such as CMP (Chemical Mechanical Polishing). 
     Moreover, as depicted in a fifth part of  FIG. 57 , the bank  531  may be formed on the glass substrate  12  in the outer peripheral portion of the two-stage side surface lens  401  in such a manner as to connect the boundary between the two-stage side surface lens  401  and the glass substrate  12 . In this case, the material of the light shielding film  521  may be only applied to the inside of the bank  531  and in the outer peripheral portion of the two-stage side surface lens  401 , and the heights of the light shielding film  521 , the lens  401 , and the bank  531  may be self-aligned based on the material of the light shielding film  521 . 
     Furthermore, as depicted in a sixth part of  FIG. 57 , the bank  531  may be formed on the glass substrate  12  in the outer peripheral portion of the two-stage side surface lens  401  in such a manner as to connect the boundary between the two-stage side surface lens  401  and the glass substrate  12 . In this case, the light shielding film  521  may be only formed inside the bank  531  and in the outer peripheral portion of the two-stage side surface lens  401  by lithography. 
     In any of these cases, the light shielding film is formed in such a manner as to cover the protrusion portion  401   a  and the side surface of the lens  401 . Accordingly, generation of a side surface flare can be reduced. 
     According to the example described above, the light shielding film is formed in the outer peripheral portion of the lens  401 . However, it is sufficient if any configuration is adopted as long as light entrance from the outer peripheral portion of the lens  401  is prevented. Accordingly, a light absorbing film may be formed instead of the light shielding film, for example. 
     &lt;22. Example of Application to Electronic Apparatus&gt; 
     The imaging device  1  depicted in  FIGS. 1, 4, and 6 to 17  described above is applicable to various types of electronic apparatuses including, for example, an imaging device such as a digital still camera and a digital video camera, a cellular phone having an imaging function, and other apparatuses having an imaging function. 
       FIG. 58  is a block diagram depicting a configuration example of an imaging device as an electronic apparatus to which the present technology is applied. 
     An imaging device  1001  depicted in  FIG. 58  includes an optical system  1002 , a shutter device  1003 , a solid-state imaging element  1004 , a driving circuit  1005 , a signal processing circuit  1006 , a monitor  1007 , and a memory  1008 , and is capable of capturing a still image and a moving image. 
     The optical system  1002  including one or a plurality of lenses guides light (incident light) received from an object toward the solid-state imaging element  1004  and captures an image of the object on a light receiving surface of the solid-state imaging element  1004 . 
     The shutter device  1003  is disposed between the optical system  1002  and the solid-state imaging element  1004 , and controls light irradiation period and a light shieling period for the solid-state imaging element  1004  under control by the driving circuit  1005 . 
     The solid-state imaging element  1004  is constituted by a package including the solid-state imaging element described above. The solid-state imaging element  1004  accumulates signal charges for a fixed period according to light imaged on the light receiving surface via the optical system  1002  and the shutter device  1003 . The signal charges accumulated in the solid-state imaging element  1004  are transferred according to a driving signal (timing signal) supplied from the driving circuit  1005 . 
     The driving circuit  1005  outputs a driving signal for controlling a transfer operation of the solid-state imaging element  1004  and a shutter operation of the shutter device  1003  to drive the solid-state imaging element  1004  and the shutter device  1003 . 
     The signal processing circuit  1006  performs various signal processes for the signal charges output from the solid-state imaging element  1004 . An image (image data) obtained by the signal processing performed by the signal processing circuit  1006  is supplied to and displayed on the monitor  1007 , or supplied to and stored (recorded) in the memory  1008 . 
     The imaging device  1001  configured as above is also capable of reducing a ghost or a flare caused by internal diffused reflection while achieving miniaturization and height reduction of the device configuration by adopting the imaging device  1  depicted in any one of  FIGS. 1, 9, and 11 to 22  in place of the optical system  1002  and the solid-state imaging element  1004  described above. 
     23. Use Examples of Solid-State Imaging Device 
       FIG. 59  is a diagram depicting use examples of the imaging device  1  described above. 
     The imaging device  1  described above is available in various cases where light such as visible light, infrared light, ultraviolet light, and X-ray is sensed as described below, for example.
         a device for capturing images used for appreciation, such as a digital camera and a portable device having a camera function   a device for traffics, such as an in-vehicle sensor for imaging front and rear, surroundings, interior, and others of an automobile for safe driving such as automatic stopping, recognizing a state of a driver, or for other purposes, a monitoring camera for monitoring traveling vehicles and roads, and a distance measurement sensor for measuring a distance between vehicles   a device for home appliances, such as TV, a refrigerator, and an air conditioner, for imaging a gesture of a user and performing a device operation according to the gesture   a device for medical treatments and healthcare, such as an endoscope, and a device for imaging blood vessels by receiving infrared light   a device for security, such as a monitoring camera for crime prevention and a camera for personal authentication   a device for beauty, such as a skin measurement device for imaging skin and a microscope for imaging scalp   a device for sports, such as an action camera and a wearable camera for sport applications   a device for agriculture, such as a camera for monitoring a state of a field and crops       

     24. Example of Application to Endoscopic Surgery System 
     The technology according to the present disclosure (present technology) is applicable to various products. For example, the technology according to the present disclosure may be applied to an endoscopic surgery system. 
       FIG. 60  is a view depicting an example of a schematic configuration of an endoscopic surgery system to which the technology according to an embodiment of the present disclosure (present technology) can be applied. 
     In  FIG. 60 , a state is illustrated in which a surgeon (medical doctor)  11131  is using an endoscopic surgery system  11000  to perform surgery for a patient  11132  on a patient bed  11133 . As depicted, the endoscopic surgery system  11000  includes an endoscope  11100 , other surgical tools  11110  such as a pneumoperitoneum tube  11111  and an energy device  11112 , a supporting arm apparatus  11120  which supports the endoscope  11100  thereon, and a cart  11200  on which various apparatus for endoscopic surgery are mounted. 
     The endoscope  11100  includes a lens barrel  11101  having a region of a predetermined length from a distal end thereof to be inserted into a body cavity of the patient  11132 , and a camera head  11102  connected to a proximal end of the lens barrel  11101 . In the example depicted, the endoscope  11100  is depicted which includes as a rigid endoscope having the lens barrel  11101  of the hard type. However, the endoscope  11100  may otherwise be included as a flexible endoscope having the lens barrel  11101  of the flexible type. 
     The lens barrel  11101  has, at a distal end thereof, an opening in which an objective lens is fitted. A light source apparatus  11203  is connected to the endoscope  11100  such that light generated by the light source apparatus  11203  is introduced to a distal end of the lens barrel  11101  by a light guide extending in the inside of the lens barrel  11101  and is irradiated toward an observation target in a body cavity of the patient  11132  through the objective lens. It is to be noted that the endoscope  11100  may be a forward-viewing endoscope or may be an oblique-viewing endoscope or a side-viewing endoscope. 
     An optical system and an image pickup element are provided in the inside of the camera head  11102  such that reflected light (observation light) from the observation target is condensed on the image pickup element by the optical system. The observation light is photo-electrically converted by the image pickup element to generate an electric signal corresponding to the observation light, namely, an image signal corresponding to an observation image. The image signal is transmitted as RAW data to a CCU  11201 . 
     The CCU  11201  includes a central processing unit (CPU), a graphics processing unit (GPU) or the like and integrally controls operation of the endoscope  11100  and a display apparatus  11202 . Further, the CCU  11201  receives an image signal from the camera head  11102  and performs, for the image signal, various image processes for displaying an image based on the image signal such as, for example, a development process (demosaic process). 
     The display apparatus  11202  displays thereon an image based on an image signal, for which the image processes have been performed by the CCU  11201 , under the control of the CCU  11201 . 
     The light source apparatus  11203  includes a light source such as, for example, a light emitting diode (LED) and supplies irradiation light upon imaging of a surgical region to the endoscope  11100 . 
     An inputting apparatus  11204  is an input interface for the endoscopic surgery system  11000 . A user can perform inputting of various kinds of information or instruction inputting to the endoscopic surgery system  11000  through the inputting apparatus  11204 . For example, the user would input an instruction or a like to change an image pickup condition (type of irradiation light, magnification, focal distance or the like) by the endoscope  11100 . 
     A treatment tool controlling apparatus  11205  controls driving of the energy device  11112  for cautery or incision of a tissue, sealing of a blood vessel or the like. A pneumoperitoneum apparatus  11206  feeds gas into a body cavity of the patient  11132  through the pneumoperitoneum tube  11111  to inflate the body cavity in order to secure the field of view of the endoscope  11100  and secure the working space for the surgeon. A recorder  11207  is an apparatus capable of recording various kinds of information relating to surgery. A printer  11208  is an apparatus capable of printing various kinds of information relating to surgery in various forms such as a text, an image or a graph. 
     It is to be noted that the light source apparatus  11203  which supplies irradiation light when a surgical region is to be imaged to the endoscope  11100  may include a white light source which includes, for example, an LED, a laser light source or a combination of them. Where a white light source includes a combination of red, green, and blue (RGB) laser light sources, since the output intensity and the output timing can be controlled with a high degree of accuracy for each color (each wavelength), adjustment of the white balance of a picked up image can be performed by the light source apparatus  11203 . Further, in this case, if laser beams from the respective RGB laser light sources are irradiated time-divisionally on an observation target and driving of the image pickup elements of the camera head  11102  are controlled in synchronism with the irradiation timings. Then images individually corresponding to the R, G and B colors can be also picked up time-divisionally. According to this method, a color image can be obtained even if color filters are not provided for the image pickup element. 
     Further, the light source apparatus  11203  may be controlled such that the intensity of light to be outputted is changed for each predetermined time. By controlling driving of the image pickup element of the camera head  11102  in synchronism with the timing of the change of the intensity of light to acquire images time-divisionally and synthesizing the images, an image of a high dynamic range free from underexposed blocked up shadows and overexposed highlights can be created. 
     Further, the light source apparatus  11203  may be configured to supply light of a predetermined wavelength band ready for special light observation. In special light observation, for example, by utilizing the wavelength dependency of absorption of light in a body tissue to irradiate light of a narrow band in comparison with irradiation light upon ordinary observation (namely, white light), narrow band observation (narrow band imaging) of imaging a predetermined tissue such as a blood vessel of a superficial portion of the mucous membrane or the like in a high contrast is performed. Alternatively, in special light observation, fluorescent observation for obtaining an image from fluorescent light generated by irradiation of excitation light may be performed. In fluorescent observation, it is possible to perform observation of fluorescent light from a body tissue by irradiating excitation light on the body tissue (autofluorescence observation) or to obtain a fluorescent light image by locally injecting a reagent such as indocyanine green (ICG) into a body tissue and irradiating excitation light corresponding to a fluorescent light wavelength of the reagent upon the body tissue. The light source apparatus  11203  can be configured to supply such narrow-band light and/or excitation light suitable for special light observation as described above. 
       FIG. 61  is a block diagram depicting an example of a functional configuration of the camera head  11102  and the CCU  11201  depicted in  FIG. 60 . 
     The camera head  11102  includes a lens unit  11401 , an image pickup unit  11402 , a driving unit  11403 , a communication unit  11404  and a camera head controlling unit  11405 . The CCU  11201  includes a communication unit  11411 , an image processing unit  11412  and a control unit  11413 . The camera head  11102  and the CCU  11201  are connected for communication to each other by a transmission cable  11400 . 
     The lens unit  11401  is an optical system, provided at a connecting location to the lens barrel  11101 . Observation light taken in from a distal end of the lens barrel  11101  is guided to the camera head  11102  and introduced into the lens unit  11401 . The lens unit  11401  includes a combination of a plurality of lenses including a zoom lens and a focusing lens. 
     The number of image pickup elements which is included by the image pickup unit  11402  may be one (single-plate type) or a plural number (multi-plate type). Where the image pickup unit  11402  is configured as that of the multi-plate type, for example, image signals corresponding to respective R, G and B are generated by the image pickup elements, and the image signals may be synthesized to obtain a color image. The image pickup unit  11402  may also be configured so as to have a pair of image pickup elements for acquiring respective image signals for the right eye and the left eye ready for three dimensional (3D) display. If 3D display is performed, then the depth of a living body tissue in a surgical region can be comprehended more accurately by the surgeon  11131 . It is to be noted that, where the image pickup unit  11402  is configured as that of stereoscopic type, a plurality of systems of lens units  11401  are provided corresponding to the individual image pickup elements. 
     Further, the image pickup unit  11402  may not necessarily be provided on the camera head  11102 . For example, the image pickup unit  11402  may be provided immediately behind the objective lens in the inside of the lens barrel  11101 . 
     The driving unit  11403  includes an actuator and moves the zoom lens and the focusing lens of the lens unit  11401  by a predetermined distance along an optical axis under the control of the camera head controlling unit  11405 . Consequently, the magnification and the focal point of a picked up image by the image pickup unit  11402  can be adjusted suitably. 
     The communication unit  11404  includes a communication apparatus for transmitting and receiving various kinds of information to and from the CCU  11201 . The communication unit  11404  transmits an image signal acquired from the image pickup unit  11402  as RAW data to the CCU  11201  through the transmission cable  11400 . 
     In addition, the communication unit  11404  receives a control signal for controlling driving of the camera head  11102  from the CCU  11201  and supplies the control signal to the camera head controlling unit  11405 . The control signal includes information relating to image pickup conditions such as, for example, information that a frame rate of a picked up image is designated, information that an exposure value upon image picking up is designated and/or information that a magnification and a focal point of a picked up image are designated. 
     It is to be noted that the image pickup conditions such as the frame rate, exposure value, magnification or focal point may be designated by the user or may be set automatically by the control unit  11413  of the CCU  11201  on the basis of an acquired image signal. In the latter case, an auto exposure (AE) function, an auto focus (AF) function and an auto white balance (AWB) function are incorporated in the endoscope  11100 . 
     The camera head controlling unit  11405  controls driving of the camera head  11102  on the basis of a control signal from the CCU  11201  received through the communication unit  11404 . 
     The communication unit  11411  includes a communication apparatus for transmitting and receiving various kinds of information to and from the camera head  11102 . The communication unit  11411  receives an image signal transmitted thereto from the camera head  11102  through the transmission cable  11400 . 
     Further, the communication unit  11411  transmits a control signal for controlling driving of the camera head  11102  to the camera head  11102 . The image signal and the control signal can be transmitted by electrical communication, optical communication or the like. 
     The image processing unit  11412  performs various image processes for an image signal in the form of RAW data transmitted thereto from the camera head  11102 . 
     The control unit  11413  performs various kinds of control relating to image picking up of a surgical region or the like by the endoscope  11100  and display of a picked up image obtained by image picking up of the surgical region or the like. For example, the control unit  11413  creates a control signal for controlling driving of the camera head  11102 . 
     Further, the control unit  11413  controls, on the basis of an image signal for which image processes have been performed by the image processing unit  11412 , the display apparatus  11202  to display a picked up image in which the surgical region or the like is imaged. Thereupon, the control unit  11413  may recognize various objects in the picked up image using various image recognition technologies. For example, the control unit  11413  can recognize a surgical tool such as forceps, a particular living body region, bleeding, mist when the energy device  11112  is used and so forth by detecting the shape, color and so forth of edges of objects included in a picked up image. The control unit  11413  may cause, when it controls the display apparatus  11202  to display a picked up image, various kinds of surgery supporting information to be displayed in an overlapping manner with an image of the surgical region using a result of the recognition. Where surgery supporting information is displayed in an overlapping manner and presented to the surgeon  11131 , the burden on the surgeon  11131  can be reduced and the surgeon  11131  can proceed with the surgery with certainty. 
     The transmission cable  11400  which connects the camera head  11102  and the CCU  11201  to each other is an electric signal cable ready for communication of an electric signal, an optical fiber ready for optical communication or a composite cable ready for both of electrical and optical communications. 
     Here, while, in the example depicted, communication is performed by wired communication using the transmission cable  11400 , the communication between the camera head  11102  and the CCU  11201  may be performed by wireless communication. 
     An example of the endoscopic surgery system to which the technology according to the present disclosure is applicable has been described above. The technology according to the present disclosure is applicable to the endoscope  11100 , (the image pickup unit  11402 ) of the camera head  11102 , (the image processing unit  11412 ) of the CCU  11201 , and others. Specifically, for example, the imaging device  1  of  FIGS. 1, 9, and 11 to 22  is applicable to the lens unit  11401  and the image pickup unit  10402 . Miniaturization and height reduction of the device configuration, and also reduction of generation of a flare and a ghost caused by internal diffused reflection are achievable by applying the technology according to the present disclosure to the lens unit  11401  and the image pickup unit  10402 . 
     Note that, while the endoscopic surgery system has been described here by way of example, the technology according to the present disclosure may be applied to others, such as a microscopic surgery system. 
     25. Example of Application to Mobile Body 
     The technology according to the present disclosure (present technology) is applicable to various products. For example, the technology according to the present disclosure may be actuated as a device mounted on any type of mobile body, such as a car, an electric car, a hybrid electric car, a motorcycle, a bicycle, a personal mobility, an airplane, a drone, a vessel, and a robot. 
       FIG. 62  is a block diagram depicting an example of schematic configuration of a vehicle control system as an example of a mobile body control system to which the technology according to an embodiment of the present disclosure can be applied. 
     The vehicle control system  12000  includes a plurality of electronic control units connected to each other via a communication network  12001 . In the example depicted in  FIG. 62 , the vehicle control system  12000  includes a driving system control unit  12010 , a body system control unit  12020 , an outside-vehicle information detecting unit  12030 , an in-vehicle information detecting unit  12040 , and an integrated control unit  12050 . In addition, a microcomputer  12051 , a sound/image output section  12052 , and a vehicle-mounted network interface (I/F)  12053  are illustrated as a functional configuration of the integrated control unit  12050 . 
     The driving system control unit  12010  controls the operation of devices related to the driving system of the vehicle in accordance with various kinds of programs. For example, the driving system control unit  12010  functions as a control device for a driving force generating device for generating the driving force of the vehicle, such as an internal combustion engine, a driving motor, or the like, a driving force transmitting mechanism for transmitting the driving force to wheels, a steering mechanism for adjusting the steering angle of the vehicle, a braking device for generating the braking force of the vehicle, and the like. 
     The body system control unit  12020  controls the operation of various kinds of devices provided to a vehicle body in accordance with various kinds of programs. For example, the body system control unit  12020  functions as a control device for a keyless entry system, a smart key system, a power window device, or various kinds of lamps such as a headlamp, a backup lamp, a brake lamp, a turn signal, a fog lamp, or the like. In this case, radio waves transmitted from a mobile device as an alternative to a key or signals of various kinds of switches can be input to the body system control unit  12020 . The body system control unit  12020  receives these input radio waves or signals, and controls a door lock device, the power window device, the lamps, or the like of the vehicle. 
     The outside-vehicle information detecting unit  12030  detects information about the outside of the vehicle including the vehicle control system  12000 . For example, the outside-vehicle information detecting unit  12030  is connected with an imaging section  12031 . The outside-vehicle information detecting unit  12030  makes the imaging section  12031  image an image of the outside of the vehicle, and receives the imaged image. On the basis of the received image, the outside-vehicle information detecting unit  12030  may perform processing of detecting an object such as a human, a vehicle, an obstacle, a sign, a character on a road surface, or the like, or processing of detecting a distance thereto. 
     The imaging section  12031  is an optical sensor that receives light, and which outputs an electric signal corresponding to a received light amount of the light. The imaging section  12031  can output the electric signal as an image, or can output the electric signal as information about a measured distance. In addition, the light received by the imaging section  12031  may be visible light, or may be invisible light such as infrared rays or the like. 
     The in-vehicle information detecting unit  12040  detects information about the inside of the vehicle. The in-vehicle information detecting unit  12040  is, for example, connected with a driver state detecting section  12041  that detects the state of a driver. The driver state detecting section  12041 , for example, includes a camera that images the driver. On the basis of detection information input from the driver state detecting section  12041 , the in-vehicle information detecting unit  12040  may calculate a degree of fatigue of the driver or a degree of concentration of the driver, or may determine whether the driver is dozing. 
     The microcomputer  12051  can calculate a control target value for the driving force generating device, the steering mechanism, or the braking device on the basis of the information about the inside or outside of the vehicle which information is obtained by the outside-vehicle information detecting unit  12030  or the in-vehicle information detecting unit  12040 , and output a control command to the driving system control unit  12010 . For example, the microcomputer  12051  can perform cooperative control intended to implement functions of an advanced driver assistance system (ADAS) which functions include collision avoidance or shock mitigation for the vehicle, following driving based on a following distance, vehicle speed maintaining driving, a warning of collision of the vehicle, a warning of deviation of the vehicle from a lane, or the like. 
     In addition, the microcomputer  12051  can perform cooperative control intended for automatic driving, which makes the vehicle to travel autonomously without depending on the operation of the driver, or the like, by controlling the driving force generating device, the steering mechanism, the braking device, or the like on the basis of the information about the outside or inside of the vehicle which information is obtained by the outside-vehicle information detecting unit  12030  or the in-vehicle information detecting unit  12040 . 
     In addition, the microcomputer  12051  can output a control command to the body system control unit  12020  on the basis of the information about the outside of the vehicle which information is obtained by the outside-vehicle information detecting unit  12030 . For example, the microcomputer  12051  can perform cooperative control intended to prevent a glare by controlling the headlamp so as to change from a high beam to a low beam, for example, in accordance with the position of a preceding vehicle or an oncoming vehicle detected by the outside-vehicle information detecting unit  12030 . 
     The sound/image output section  12052  transmits an output signal of at least one of a sound and an image to an output device capable of visually or auditorily notifying information to an occupant of the vehicle or the outside of the vehicle. In the example of  FIG. 62 , an audio speaker  12061 , a display section  12062 , and an instrument panel  12063  are illustrated as the output device. The display section  12062  may, for example, include at least one of an on-board display and a head-up display. 
       FIG. 63  is a diagram depicting an example of the installation position of the imaging section  12031 . 
     In  FIG. 63 , the imaging section  12031  includes imaging sections  12101 ,  12102 ,  12103 ,  12104 , and  12105 . 
     The imaging sections  12101 ,  12102 ,  12103 ,  12104 , and  12105  are, for example, disposed at positions on a front nose, sideview mirrors, a rear bumper, and a back door of the vehicle  12100  as well as a position on an upper portion of a windshield within the interior of the vehicle. The imaging section  12101  provided to the front nose and the imaging section  12105  provided to the upper portion of the windshield within the interior of the vehicle obtain mainly an image of the front of the vehicle  12100 . The imaging sections  12102  and  12103  provided to the sideview mirrors obtain mainly an image of the sides of the vehicle  12100 . The imaging section  12104  provided to the rear bumper or the back door obtains mainly an image of the rear of the vehicle  12100 . The imaging section  12105  provided to the upper portion of the windshield within the interior of the vehicle is used mainly to detect a preceding vehicle, a pedestrian, an obstacle, a signal, a traffic sign, a lane, or the like. 
     Incidentally,  FIG. 63  depicts an example of photographing ranges of the imaging sections  12101  to  12104 . An imaging range  12111  represents the imaging range of the imaging section  12101  provided to the front nose. Imaging ranges  12112  and  12113  respectively represent the imaging ranges of the imaging sections  12102  and  12103  provided to the sideview mirrors. An imaging range  12114  represents the imaging range of the imaging section  12104  provided to the rear bumper or the back door. A bird&#39;s-eye image of the vehicle  12100  as viewed from above is obtained by superimposing image data imaged by the imaging sections  12101  to  12104 , for example. 
     At least one of the imaging sections  12101  to  12104  may have a function of obtaining distance information. For example, at least one of the imaging sections  12101  to  12104  may be a stereo camera constituted of a plurality of imaging elements, or may be an imaging element having pixels for phase difference detection. 
     For example, the microcomputer  12051  can determine a distance to each three-dimensional object within the imaging ranges  12111  to  12114  and a temporal change in the distance (relative speed with respect to the vehicle  12100 ) on the basis of the distance information obtained from the imaging sections  12101  to  12104 , and thereby extract, as a preceding vehicle, a nearest three-dimensional object in particular that is present on a traveling path of the vehicle  12100  and which travels in substantially the same direction as the vehicle  12100  at a predetermined speed (for example, equal to or more than 0 km/hour). Further, the microcomputer  12051  can set a following distance to be maintained in front of a preceding vehicle in advance, and perform automatic brake control (including following stop control), automatic acceleration control (including following start control), or the like. It is thus possible to perform cooperative control intended for automatic driving that makes the vehicle travel autonomously without depending on the operation of the driver or the like. 
     For example, the microcomputer  12051  can classify three-dimensional object data on three-dimensional objects into three-dimensional object data of a two-wheeled vehicle, a standard-sized vehicle, a large-sized vehicle, a pedestrian, a utility pole, and other three-dimensional objects on the basis of the distance information obtained from the imaging sections  12101  to  12104 , extract the classified three-dimensional object data, and use the extracted three-dimensional object data for automatic avoidance of an obstacle. For example, the microcomputer  12051  identifies obstacles around the vehicle  12100  as obstacles that the driver of the vehicle  12100  can recognize visually and obstacles that are difficult for the driver of the vehicle  12100  to recognize visually. Then, the microcomputer  12051  determines a collision risk indicating a risk of collision with each obstacle. In a situation in which the collision risk is equal to or higher than a set value and there is thus a possibility of collision, the microcomputer  12051  outputs a warning to the driver via the audio speaker  12061  or the display section  12062 , and performs forced deceleration or avoidance steering via the driving system control unit  12010 . The microcomputer  12051  can thereby assist in driving to avoid collision. 
     At least one of the imaging sections  12101  to  12104  may be an infrared camera that detects infrared rays. The microcomputer  12051  can, for example, recognize a pedestrian by determining whether or not there is a pedestrian in imaged images of the imaging sections  12101  to  12104 . Such recognition of a pedestrian is, for example, performed by a procedure of extracting characteristic points in the imaged images of the imaging sections  12101  to  12104  as infrared cameras and a procedure of determining whether or not it is the pedestrian by performing pattern matching processing on a series of characteristic points representing the contour of the object. When the microcomputer  12051  determines that there is a pedestrian in the imaged images of the imaging sections  12101  to  12104 , and thus recognizes the pedestrian, the sound/image output section  12052  controls the display section  12062  so that a square contour line for emphasis is displayed so as to be superimposed on the recognized pedestrian. The sound/image output section  12052  may also control the display section  12062  so that an icon or the like representing the pedestrian is displayed at a desired position. 
     An example of the vehicle control system to which the technology according to the present disclosure is applicable has been described above. The technology according to the present disclosure is applicable to the imaging section  12031  in the configuration described above, for example. Specifically, for example, the imaging device  1  of  FIGS. 1, 9, and 11 to 22  is applicable to the imaging section  12031 . Miniaturization and height reduction of the device configuration, and also reduction of generation of a flare and a ghost caused by internal diffused reflection are achievable by applying the technology according to the present disclosure to the imaging section  12031 . 
     Note that the present disclosure may have following configurations. 
     &lt;1&gt; 
     An imaging device including: 
     a solid-state imaging element that generates a pixel signal by photoelectric conversion according to a light amount of incident light; 
     an integrated configuration unit that integrates a function of fixing the solid-state imaging element and a function of cutting off infrared light of the incident light; and 
     a lens group that includes a plurality of lenses and focuses the incident light on a light receiving surface of the solid-state imaging element, in which 
     the integrated configuration unit deploys a lowermost layer lens of the lens group in a foremost stage in a direction for receiving the incident light, the lowermost layer lens constituting a lowermost layer with respect to an incident direction of the incident light, and 
     the lowermost layer lens is an aspherical and recessed lens, an effective region for converging the incident light on the solid-state imaging element being defined, a size of the effective region in a vertical direction with respect to the incident light being smaller than a size of an external shape of the lowermost layer lens, the size of the external shape of the lowermost layer lens in the vertical direction with respect to the incident light being smaller than a size of the solid-state imaging element. 
     &lt;2&gt; 
     The imaging device according to &lt;1&gt;, in which 
     the effective region is defined substantially at a center with respect to a width of the lowermost layer lens in the vertical direction with respect to the incident light, a non-effective region for not necessarily converging the incident light on the solid-state imaging element being defined in an outer peripheral portion of the effective region, and 
     the non-effective region is produced by extending a structure that functions as the effective region at a boundary with the effective region. 
     &lt;3&gt; 
     The imaging device according to &lt;1&gt; or &lt;2&gt;, in which a cross-sectional shape of an outer peripheral side surface portion of the lowermost layer lens as viewed in the vertical direction with respect to the incident direction of the incident light has at least any one of a vertical shape, a tapered shape, a round shape, or a multistep side surface shape. 
     &lt;4&gt; 
     The imaging device according to any one of &lt;1&gt; to &lt;3&gt;, in which a hemming bottom portion is formed on an outer peripheral side surface of the lowermost layer lens at a boundary with the solid-state imaging element. 
     &lt;5&gt; 
     The imaging device according to &lt;4&gt;, in which the hemming bottom portion has a square or round cross-sectional shape as viewed in the vertical direction with respect to the incident direction of the incident light. 
     &lt;6&gt; 
     The imaging device according to any one of &lt;1&gt; to &lt;5&gt;, in which a corner of the lowermost layer lens has a shape that includes a polygonal shape having an obtuse angle, a round shape, a recessed portion, or a protruding portion. 
     &lt;7&gt; 
     The imaging device according to any one of &lt;1&gt; to &lt;6&gt;, in which a refractive film having a refractive index different from a refractive index of the lowermost layer lens is formed on an outer peripheral side surface portion of the lowermost layer lens. 
     &lt;8&gt; 
     The imaging device according to &lt;7&gt;, in which the refractive index of the refractive film is higher than the refractive index of the lowermost layer lens. 
     &lt;9&gt; 
     The imaging device according to &lt;7&gt;, in which the refractive index of the refractive film is lower than the refractive index of the lowermost layer lens. 
     &lt;10&gt; 
     The imaging device according to &lt;7&gt;, in which a thickness of the refractive film in the incident direction of the incident light on an outer peripheral side surface of the lowermost layer lens is any one of a thickness identical to a thickness of the lens, a thickness larger than the thickness of the lowermost layer lens, and a thickness smaller than the thickness of the lowermost layer lens. 
     &lt;11&gt; 
     The imaging device according to any one of &lt;1&gt; to &lt;10&gt;, in which a front surface of the lowermost layer lens has an anti-reflection function. 
     &lt;12&gt; 
     The imaging device according to any one of &lt;1&gt; to &lt;11&gt;, in which 
     an IRCF (infrared cut filter) is formed between the solid-state imaging element and the lowermost layer lens in a stage before the solid-state imaging element with respect to the incident direction of the incident light, a glass substrate being formed in a stage before the IRCF, and 
     the IRCF includes two layers, one of the layers being formed on the solid-state imaging element, the other layer being formed on the glass substrate, the IRCF in the one layer and the IRCF in the other layer being joined to each other via an adhesive in a mutually opposed state. 
     &lt;13&gt; 
     The imaging device according to &lt;12&gt;, in which an elastic modulus of the glass substrate is higher than an elastic modulus of the IRCF, the elastic modulus of the IRCF being higher than an elastic modulus of the adhesive. 
     &lt;14&gt; 
     The imaging device according to &lt;12&gt;, in which a size of the solid-state imaging element in the vertical direction with respect to the incident direction of the incident light is larger than each of sizes of the glass substrate, the IRCF, and the adhesive. 
     &lt;15&gt; 
     The imaging device according to &lt;14&gt;, in which a size of the glass substrate in the vertical direction with respect to the incident direction of the incident light is larger than each of the sizes of the IRCF and the adhesive. 
     &lt;16&gt; 
     The imaging device according to &lt;14&gt;, in which the size of the glass substrate in the vertical direction with respect to the incident direction of the incident light is smaller than each of the sizes of the IRCF and the adhesive. 
     &lt;17&gt; 
     The imaging device according to &lt;16&gt;, in which the size of the adhesive in the vertical direction with respect to the incident direction of the incident light is substantially equal to the size of the IRCF. 
     &lt;18&gt; 
     The imaging device according to &lt;16&gt;, in which the size of the adhesive in the vertical direction with respect to the incident direction of the incident light is smaller than the size of the IRCF. 
     &lt;19&gt; 
     The imaging device according to &lt;12&gt;, in which an anti-reflection film is formed at least at any one of a position on the glass substrate, a position between the glass substrate and the IRCF, a position between the IRCF formed on the glass substrate and the adhesive, or a position between the adhesive and the IRCF formed on the solid-state imaging element. 
     &lt;20&gt; 
     The imaging device according to &lt;12&gt;, in which an anti-reflection film or a light absorbing film is formed on a side surface portion included in an entire side surface of the glass substrate, the IRCF formed on the glass surface, the adhesive, the IRCF formed on the solid-state imaging element, and the solid-state imaging element except for at least a side surface portion of the solid-state imaging element. 
     REFERENCE SIGNS LIST 
       1  Imaging device,  10  Integrated configuration unit,  11  Solid-state imaging element (having CPS structure),  11   a  Lower substrate (logic substrate),  11   b  Upper substrate (pixel sensor substrate),  11   c  Color filter,  11   d  On-chip lens,  12  Glass substrate,  13  Adhesive,  14  IRCF (infrared cut filter),  14 ′ IRCF glass substrate,  15  Adhesive,  16  Lens group,  17  Circuit board,  18  Actuator,  19  Connector,  20  Spacer,  21  Pixel region,  22  Control circuit,  23  Logic circuit,  32  Pixel,  51  Photodiode,  81  Silicon substrate,  83  Wiring layer,  86  Insulation film,  88  Silicon through electrode,  91  Solder mask,  101  Silicon substrate,  103  Wiring layer,  105  Chip through electrode,  106  Connection wiring,  109  Silicon through electrode,  131  Lens,  151  Adhesive,  171  Lens group,  191  Solid-state imaging element (having COB structure),  192  Wire bond,  211  Infrared cut resin,  231  Glass substrate,  231   a  Protrusion,  231   b  Cavity,  251  Coating agent having infrared cut function,  271  Lens,  271   a  AR coating,  291  Lens,  291   a  Anti-reflection treatment portion,  301  Infrared cut lens,  321  Glass substrate,  351  Refractive film,  371 ,  371 - 1  to  371 - 4 ,  381  Added film,  401 ,  401 A to  401 U,  401 AA to  401 AH Lens,  401   a  Protrusion portion,  401   b ,  401   b ′ Hemming bottom portion,  401   d  Hemming bottom portion,  402 ,  402 A to  402 U,  402 AA to  402 AH,  402 -P 1  to  402 -P 5  AR coating,  451  Substrate,  452 ,  452 ′,  452 ″,  452 ′″ Mold,  453  Light shielding film,  461  Ultraviolet curing resin,  461   a  Leak portion,  501 ,  501 ′,  501 A to  501 K Alignment mark,  521  Light shielding film,  531  Bank