Patent Publication Number: US-2022238565-A1

Title: Electro-optical device and electronic apparatus

Description:
The present application is based on, and claims priority from JP Application Serial Number 2021-008865, filed Jan. 22, 2021, the disclosure of which is hereby incorporated by reference herein in its entirety. 
     BACKGROUND 
     1. Technical Field 
     The present disclosure relates to an electro-optical device and an electronic apparatus. 
     2. Related Art 
     For electronic devices such as projectors, for example, an electro-optical device such as a liquid crystal display whose optical characteristics can be varied for each pixel is used. 
     The electro-optical device described in JP-A-2017-72741 includes an element substrate, a counter substrate, and a liquid crystal layer sandwiched by these substrates. The element substrate includes a scanning line, a transistor, a pixel capacitor, a data line, and a pixel electrode provided in this order on the substrate. The scanning line is formed of a light-shielding conductive material. Light incident from the substrate toward the transistor is shielded by arranging the scanning line between the transistor and the substrate. By shielding the light incident on the transistor, it is possible to prevent operation of the transistor from becoming unstable, and thus to suppress possibility of display defects such as luminance unevenness of the pixels. 
     In order to further enhance the light-shielding property to the transistor, for example, a measure for increasing the thickness of the scanning line can be considered. However, when the thickness of the scanning line is increased, the substrate may be cracked due to the difference in thermal stress between the scanning line and the substrate during manufacturing. Accordingly, other measures capable of further improving the light-shielding properties of the transistor with respect to the light entering from the substrate are needed. 
     SUMMARY 
     An aspect of an electro-optical device according to the present disclosure includes a substrate having light-transmissivity, a capacitance element having light-transmissivity and including a first electrode, a dielectric layer, and a second electrode, a first insulating film having light-transmissivity, a light-shielding film, a second insulating film having light-transmissivity, and a transistor. The first electrode, the dielectric layer, the second electrode, the first insulating film, the light-shielding film, the second insulating film, and the transistor are layered in this order from the first substrate side, and an interfacial reflection at the first insulating film side of the light-shielding film is greater than an interfacial reflection at the dielectric layer side of the first electrode with respect to light entering from the first substrate. 
     Further, an aspect of the electro-optical device according to the present disclosure includes a substrate having light-transmissivity, a capacitance element having light-transmissivity and including a first electrode, a dielectric layer, and a second electrode, a first insulating film having light-transmissivity, a light-shielding film, a second insulating film having light-transmissivity, and a transistor. The first electrode, the dielectric layer, the second electrode, the first insulating film, the light-shielding film, the second insulating film, and the transistor are layered in this order from the substrate side, the first insulating film has a thickness thicker than that of the first electrode, the dielectric layer, the second electrode, or the light-shielding film, and the first insulating film has a refractive index smaller than that of the second electrode. 
     An aspect of an electronic apparatus according to the present disclosure includes the above-described electro-optical device and a control unit configured to control operation of the electro-optical device. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a plan view of an electro-optical device according to an exemplary embodiment. 
         FIG. 2  is a cross-sectional view taken along a line AA of the electro-optical device illustrated in  FIG. 1 . 
         FIG. 3  is an equivalent circuit diagram illustrating an electrical configuration of the element substrate of  FIG. 1 . 
         FIG. 4  is a cross-sectional view illustrating a part of the element substrate illustrated in  FIG. 2 . 
         FIG. 5  is a diagram schematically illustrating a part of the element substrate illustrated in  FIG. 4 . 
         FIG. 6  is a table illustrating an example of a thickness of an insulating film illustrated in  FIG. 5 . 
         FIG. 7  is a table illustrating an example of a total thickness of a first electrode and a second electrode illustrated in  FIG. 5 . 
         FIG. 8  is a diagram illustrating a reflectance in a green wavelength region. 
         FIG. 9  is a diagram illustrating an OD value in the green wavelength region. 
         FIG. 10  is a perspective view illustrating a personal computer as an example of an electronic apparatus. 
         FIG. 11  is a plan view illustrating a smart phone as an example of the electronic apparatus. 
         FIG. 12  is a schematic diagram illustrating a projector as an example of the electronic apparatus. 
     
    
    
     DESCRIPTION OF EXEMPLARY EMBODIMENTS 
     Preferred embodiments of the present disclosure will be described below with reference to the accompanying drawings. Note that, in the drawings, dimensions or scales of sections are differed from actual dimensions or scales as appropriate, and some of the sections are schematically illustrated to make them easily recognizable. Further, the scope of the present disclosure is not limited to these embodiments unless otherwise stated to limit the present disclosure in the following descriptions. 
     1. Electro-Optical Apparatus 
     1A. Basic Configuration 
       FIG. 1  is a plan view of an electro-optical device  100  according to an exemplary embodiment.  FIG. 2  is a cross-sectional view taken along a line AA of the electro-optical device  100  illustrated in  FIG. 1 . Note that in  FIG. 1 , an illustration of a counter substrate  3  is omitted. Further, for convenience of explanation, the description will be made appropriately using an X-axis, a Y-axis, and a Z-axis orthogonal to each other. Further, one direction along the X-axis is described as an X1 direction, and the direction opposite to the X1 direction is described as an X2 direction. Similarly, one direction along the Y-axis is described as a Y1 direction, and the direction opposite the Y1 direction is described as a Y2 direction. One direction along the Z-axis is described as a Z1 direction, and the direction opposite the Z1 direction is described as a Z2 direction. Further, in the following, viewing in the Z1 direction or the Z2 direction is referred to as “plan view”, and viewing from a direction perpendicular to a cross section including the Z-axis is referred to as “cross-sectional view”. 
     The electro-optical device  100  illustrated in  FIGS. 1 and 2  is a transmission-type electro-optical device of an active matrix drive system. As illustrated in  FIG. 2 , the electro-optical device  100  includes an element substrate  2 , the counter substrate  3 , a sealing member  4  having a frame shape, and a liquid crystal layer  5 . The element substrate  2 , the liquid crystal layer  5 , and the counter substrate  3  are arranged in this order in the Z1 direction. Further, the shape of the electro-optical device  100  illustrated in  FIG. 1  in plan view is square, but may be, for example, circular. 
     The element substrate  2  illustrated in  FIG. 2  is a substrate including a plurality of TFTs (Thin Film Transistor) described later. The element substrate  2  includes a first substrate  21  having light-transmissivity, a laminate  22  having light-transmissivity, a plurality of pixel electrodes  25  having light-transmissivity, and a first alignment film  29  having light-transmissivity. Further, although not illustrated, the element substrate  2  includes a plurality of dummy pixel electrodes that surround the plurality of pixel electrodes  25  in plan view. In the following description, “light-transmissivity” refers to transparency to visible light, and means that a transmittance of visible light may be greater than or equal to 50%. 
     The first substrate  21 , the laminate  22 , the plurality of pixel electrodes  25 , and the first alignment film  29  are layered in this order in the Z1 direction. The first substrate  21  is an example of a “substrate”. The first substrate  21  is a flat plate having light-transmissivity and insulating properties. The first substrate  21  is, for example, a glass substrate or a quartz substrate. The laminate  22  includes a plurality of insulating films having light-transmissivity and various wirings arranged between each of the plurality of insulating films. The laminate  22  will be described later. Further, the pixel electrode  25  has light-transmissivity and conductivity. The pixel electrode  25  is used to apply an electric field to the liquid crystal layer  5 . The pixel electrode  25  includes, for example, a transparent conductive material such as Indium Tin Oxide (ITO), Indium Zinc Oxide (IZO), and Fluorine-doped tin oxide (FTO). The first alignment film  29  has light-transmissivity and insulating properties. The first alignment film  29  aligns the liquid crystal molecules contained in the liquid crystal layer  5 . The first alignment film  29  is arranged so as to cover the plurality of pixel electrodes  25 . The material of the first alignment film  29  is, for example, polyimide, silicon oxide, and the like. 
     The counter substrate  3  is a substrate arranged so as to face the element substrate  2 . The counter substrate  3  includes a second substrate  31  having light-transmissivity, an insulating layer  32  having light-transmissivity, a common electrode  33  having light-transmissivity, and a second alignment film  34  having light-transmissivity. Further, although not illustrated, the counter substrate  3  includes a light-shielding parting that surrounds the plurality of pixel electrodes  25  in plan view. In the present specification, “light-shielding property” means the light-shielding property to visible light, and means that a transmittance of visible light may be less than 50%, and more preferably may be equal to or less than 10%. 
     The second substrate  31 , the insulating layer  32 , the common electrode  33 , and the second alignment film  34  are layered in this order in the Z2 direction. The second substrate  31  is a flat plate having light-transmissivity and insulating properties. The second substrate  31  is, for example, a glass substrate or a quartz substrate. The insulating layer  32  has light-transmissivity and insulating properties, and is formed from, for example, an inorganic material including silicon such as silicon oxide. The common electrode  33  is a counter electrode that is arranged with respect to the plurality of pixel electrodes  25  via the liquid crystal layer  5 . The common electrode  33  is used to apply an electric field to the liquid crystal layer  5 . The common electrode  33  has light-transmissivity and conductivity. The common electrode  33  includes, for example, a transparent conductive material such as ITO, IZO and FTO. The second alignment film  34  has light-transmissivity and insulating properties. The second alignment film  34  aligns the liquid crystal molecules contained in the liquid crystal layer  5 . The material of the second alignment film  34  is, for example, polyimide, silicon oxide, and the like. 
     The sealing member  4  is arranged between the element substrate  2  and the counter substrate  3 . The sealing member  4  is formed using an adhesive containing various types of curable resins such as epoxy resin, for example. The sealing member  4  may include a gap material made of an inorganic material such as glass. 
     The liquid crystal layer  5  is arranged in a region surrounded by the element substrate  2 , the counter substrate  3 , and the sealing member  4 . The optical characteristics of the liquid crystal layer  5  vary according to the electric field. The liquid crystal layer  5  contains liquid crystal molecules having positive or negative dielectric anisotropy. The alignment of the liquid crystal molecule varies according to the voltage applied to the liquid crystal layer  5 . 
     As illustrated in  FIG. 1 , a plurality of scanning line drive circuits  11 , a data line drive circuit  12 , and a plurality of external terminals  13  are arranged at the element substrate  2 . Although not illustrated, a portion of the plurality of external terminals  13  is coupled to a wiring drawn from the scanning line drive circuit  11  or the data line drive circuit  12 . Further, the plurality of external terminals  13  include terminals to which a common potential is applied. The terminal is electrically coupled to the common electrode  33  of the counter substrate  3  via a wiring and a conductive material (not illustrated). 
     The electro-optical device  100  includes a display region A 10  that displays an image, and a peripheral region A 20  located outside the display region A 10  in plan view. A plurality of pixels P arranged in a matrix pattern are provided in the display region A 10 . The plurality of pixel electrodes  25  are arranged one-to-one with respect to the plurality of pixels P. The common electrode  33  described above is commonly provided to the plurality of pixels P. Further, the peripheral region A 20  surrounds the display region A 10  in plan view. The scanning line drive circuit  11  and the data line drive circuit  12  are arranged in the peripheral region A 20 . 
     In the present embodiment, the electro-optical device  100  is a transmission-type. For example, an image is displayed by modulating the light incident on the counter substrate  3  by it is emitted from the element substrate  2 . Note that an image may be displayed by modulating the light incident on the element substrate  2  by it is emitted from the counter substrate  3 . 
     Further, the electro-optical device  100  is applied to, for example, a display device that performs color display such as a personal computer and a smart phone, which will be described later. When applied to the display device, a color filter is appropriately used for the electro-optical device  100 . Further, the electro-optical device  100  is applied to, for example, a projection-type projector described later. In this case, the electro-optical device  100  functions as a light bulb. Note that in this case, the color filter is omitted from the electro-optical device  100 . 
     1B. Electrical Configuration of Element Substrate  2   
       FIG. 3  is an equivalent circuit diagram illustrating an electrical configuration of the element substrate  2  of  FIG. 1 . The laminate  22  of the element substrate  2  is provided with a plurality of transistors  23 , n pieces of scanning lines  241 , m pieces of data lines  242 , and n pieces of constant potential lines  243  illustrated in  FIG. 3 . n and m are each an integer of 2 or greater. The transistor  23  is arranged corresponding to each intersection of n pieces of scanning lines  241  and m pieces of data lines  242 . Each transistor  23  is, for example, a TFT that functions as a switching element. Each transistor  23  includes a gate, a source, and a drain. 
     Each of the n pieces of scanning lines  241  extends in the X1 direction, and the n pieces of scanning lines  241  are arranged at equal intervals in the Y1 direction. Each of the n pieces of scanning lines  241  is electrically coupled to the gate of the corresponding plurality of transistors  23 . The n pieces of scanning lines  241  are electrically coupled to the scanning line drive circuit  11  illustrated in  FIG. 1 . Scanning signals G 1 , G 2 , . . . , and Gn are line-sequentially supplied to one to n pieces of the scanning lines  241  from the scanning line drive circuit  11 . 
     Each of the m pieces of data lines  242  illustrated in  FIG. 3  extends in the Y1 direction, and the m pieces of data lines  242  are arranged at equal intervals in the X1 direction. Each of the m pieces of data lines  242  is electrically coupled to the source of the corresponding plurality of transistors  23 . The m pieces of data lines  242  are electrically coupled to the data line drive circuit  12  illustrated in  FIG. 1 . Image signals S 1 , S 2 , . . . , and Sm are supplied in parallel to one to m pieces of the data lines  242  from the data line drive circuit  12 . 
     The n pieces of scanning lines  241  and the m pieces of data lines  242  illustrated in  FIG. 3  are electrically insulated from each other and are arranged in a lattice-like pattern in plan view. A region surrounded by two adjacent scanning lines  241  and two adjacent data lines  242  corresponds to the pixel P. Each pixel electrode  25  is electrically coupled to the drain of the corresponding transistor  23 . 
     Each of the n pieces of constant potential lines  243  extends in the Y1 direction, and the n pieces of constant potential lines  243  are arranged at equal intervals in the X1 direction. Further, the n pieces of constant potential lines  243  are electrically insulated from the m pieces of data lines  242  and the n pieces of scanning lines  241 , and are arranged at intervals from these. A fixed potential such as a ground potential is applied to each constant potential line  243 . Each of the n pieces of constant potential lines  243  is a capacitance line electrically coupled to corresponding capacitance element  26 . Each capacitance element  26  is a retention capacitor for holding the potential of the pixel electrode  25 . Note that the plurality of capacitance elements  26  are electrically coupled to the plurality of pixel electrodes  25  in a one-to-one manner. The plurality of capacitance elements  26  are electrically coupled to the drain of the plurality of transistors  23  in a one-to-one manner. 
     The scanning signals G 1 , G 2 , . . . , and Gn become sequentially active and n pieces of scanning lines  241  are sequentially selected, then the transistor  23  coupled to the selected scanning line  241  is turned to be on-state. Then, the image signals S 1 , S 2 , . . . , and Sm having magnitudes commensurate with the grayscale to be displayed are transmitted, via the m pieces of data lines  242 , to the pixel P corresponding to the selected scanning line  241 , and are then applied to the pixel electrodes  25 . This allows a voltage in accordance with the grayscale to be displayed to be applied to the liquid crystal capacitor formed between the pixel electrode  25  and the common electrode  33  of  FIG. 2 , where the alignment of the liquid crystal molecules varies in accordance with the applied voltage. The applied voltage is held by the capacitance element  26 . Such a variation in the alignment of the liquid crystal molecules causes the light to be modulated, to thus enable grayscale display. 
     1C. Specific Configuration of Element Substrate  2   
       FIG. 4  is a cross-sectional view illustrating a part of the element substrate  2  illustrated in  FIG. 2 . As illustrated in  FIG. 4 , the element substrate  2  includes the first substrate  21 , the laminate  22 , the plurality of pixel electrodes  25 , and the first alignment film  29 . 
     The laminate  22  has a plurality of insulating films  221 ,  222 ,  223 ,  224 ,  225 ,  226 ,  227 ,  228  and  229  arranged in the Z1 direction. The insulating films  221  to  229  have light-transmissivity and insulating properties. The material of each of the insulating films  221  to  229  is, for example, an inorganic material such as silicon oxynitride and silicon oxide. The insulating film  222  is an example of a “first insulating film”, and the insulating film  223  is an example of a “second insulating film”. 
     A plurality of wirings and the like are arranged in the laminate  22 . Specifically, the transistor  23 , the scanning line  241 , the data line  242 , the constant potential line  243 , and the capacitance element  26  are arranged in the laminate  22 . Further, a light-shielding film  244 , a source relay electrode  246 , a first drain relay electrode  245 , and a second drain relay electrode  247  are arranged in the laminate  22 . Further, contacts  271 ,  272 ,  273 ,  274 , and  275  are arranged in the laminate  22 . Each of the contacts  271  to  275  is arranged in a contact hole that is a through hole formed in the laminate  22 . The contacts  271  to  275  are columnar plugs or trench wirings formed on the inner wall surface of the contact hole. 
     The capacitance element  26  is arranged on the first substrate  21 . The capacitance element  26  includes a first electrode  261 , a second electrode  262 , and a dielectric layer  263 . The first electrode  261 , the dielectric layer  263 , and the second electrode  262  are arranged in this order in the Z1 direction. 
     The light-shielding film  244  is arranged on the insulating film  222 . The light-shielding film  244  has light-shielding properties and conductivity. When the scanning line  241  is a first scanning line, the light-shielding film  244  functions as a second scanning line. Note that the light-shielding film  244  may function as the second scanning line, or may be insulated from the scanning line  241 . 
     The transistor  23  is arranged on the insulating film  223 . The transistor  23  includes a semiconductor layer  231 , a gate electrode  232 , and a gate insulating film  233 . The semiconductor layer  231  is arranged on the insulating film  223 . The semiconductor layer  231  has a lightly doped drain (LDD) structure. Specifically, the semiconductor layer  231  includes a channel region  231   a , a drain region  231   b , a source region  231   c , a low concentration drain region  231   d , and a low concentration source region  231   e . The channel region  231   a  is located between the drain region  231   b  and the source region  231   c . The low concentration drain region  231   d  is located between the channel region  231   a  and the drain region  231   b . The low concentration source region  231   e  is located between the channel region  231   a  and the source region  231   c . The semiconductor layer  231  is formed, for example, by forming polysilicon. The region other than the channel region  231   a  are doped with impurities that enhance conductivity. The impurity concentration in the low concentration drain region  231   d  is lower than the impurity concentration in the drain region  231   b . The impurity concentration in the low concentration source region  231   e  is lower than the impurity concentration in the source region  231   c . Note that, for example, the low concentration source region  231   e  may be omitted. 
     Although a plan view is omitted, the gate electrode  232  overlaps the channel region  231   a  of the semiconductor layer  231  in plan view. The gate electrode  232  is formed, for example, by doping polysilicon with impurities that enhance conductivity. The gate electrode  232  may be formed by using a material having conductivity of a metal, a metal oxide, and a metal compound. Further, the gate insulating film  233  is interposed between the gate electrode  232  and the channel region  231   a . The gate insulating film  233  is made of silicon oxide formed by, for example, thermal oxidation or a CVD (chemical vapor deposition) method. 
     The scanning line  241  and the first drain relay electrode  245  are arranged on the insulating film  225 . The scanning line  241  is, for example, integrally formed with the gate electrode  232 . The first drain relay electrode  245  is coupled to the first electrode  261  included in the capacitance element  26  described above via the contact  271 . 
     The source relay electrode  246  and the second drain relay electrode  247  are arranged on the insulating film  226 . The source relay electrode  246  is coupled to the source region  231   c  of the semiconductor layer  231  via the contact  272 . The second drain relay electrode  247  is coupled to the drain region  231   b  of the semiconductor layer  231  and the first drain relay electrode  245  via the contact  273 . 
     The data line  242  is arranged on the insulating film  227 . The data line  242  is coupled to the source relay electrode  246  via the contact  274 . The constant potential line  243  is arranged on the insulating film  228 . The constant potential line  243  is electrically coupled to the second electrode  262  of the capacitance element  26  via a contact or the like (not illustrated). The pixel electrode  25  is arranged on the insulating film  229 . The pixel electrode  25  is coupled to the second drain relay electrode  247  described above via the contact  275 . 
     Examples of each material of the scanning line  241 , the data line  242 , the constant potential line  243 , the light-shielding film  244 , the source relay electrode  246 , the first drain relay electrode  245 , and the second drain relay electrode  247  described above include, for example, metal materials such as metals such as tungsten (W), titanium (Ti), chromium (Cr), iron (Fe), and aluminum (Al), metal nitrides such as titanium nitride, and metal oxides such as tungsten silicide. Furthermore, the various wirings and the like are constituted by a single layer or a laminate of these metal materials. Examples of each material of the contacts  271  to  280  include, for example, metal materials such as metals such as tungsten, cobalt (Co), and copper (Cu), metal nitrides, and metal oxides. 
     Further, although a plan view is omitted, the above-described various wirings and the like are arranged so as to surround the pixel electrode  25  in the plan view. The plurality of pixel electrodes  25  are arranged in a matrix in plan view, and the various wirings and the like are arranged in a frame shape surrounding the pixel electrodes  25  in plan view. A region in which the pixel electrode  25  is arranged in plan view is a region through which light is transmitted. 
     Note that the arrangement of the various wirings and the like included in the element substrate  2  illustrated in  FIG. 4  is an example, and is not limited to the arrangement illustrated in  FIG. 4 . 
     1D. Configuration Below Transistor  23   
       FIG. 5  is a diagram schematically illustrating a part of the element substrate  2  illustrated in  FIG. 4 . As described above, the element substrate  2  includes the first substrate  21  as a substrate, the capacitance element  26 , the insulating film  222  as the first insulating film, the light-shielding film  244 , and the insulating film  223  as the second insulating film, and the transistor  23 . Accordingly, as illustrated in  FIG. 5 , the first substrate  21 , the capacitance element  26 , the insulating film  222 , the light-shielding film  244 , and the insulating film  223  are present in the layer below the transistor  23 . Further, as described above, the capacitance element  26  includes the first electrode  261 , the dielectric layer  263 , and the second electrode  262 . The first electrode  261 , the dielectric layer  263 , the second electrode  262 , the insulating film  222 , the light-shielding film  244 , the insulating film  223 , and the transistor  23  are layered in this order from the first substrate  21 . 
     The capacitance element  26  and the insulating film  222  transmit a portion of light LL incident on the first substrate  21  and reflect another portion of the light LL. Specifically, at an interface F 1  between the first substrate  21  and the first electrode  261 , at an interface F 2  between the first electrode  261  and the dielectric layer  263 , at an interface F 3  between the dielectric layer  263  and the second electrode  262 , at an interface F 4  between the second electrode  262  and the insulating film  222 , and at an interface F 5  between the insulating film  222  and the light-shielding film  244 , a portion of the light LL is transmitted and another portion of the light LL is reflected. Note that the light-shielding film  244  may also transmit a portion of the light LL and reflect another portion of the light LL. 
     Each refractive index of the first electrode  261 , the second electrode  262 , and the light-shielding film  244  is higher than each refractive index of the dielectric layer  263 , the insulating film  222 , and the insulating film  223 . The refractive index of the light-shielding film  244  is the highest. Then, the first electrode  261  with the high refractive index, the dielectric layer  263  with the low refractive index, the second electrode  262  with the high refractive index, the insulating film  222  with the low refractive index, and the light-shielding film  244  with the high refractive index are layered in this order. Therefore, the portion of the light LL can be reflected at each of the interfaces F 1  to F 5 . Therefore, the portion of the light LL incident from the first substrate  21  becomes reflected light L 1  at the interface F 1 , reflected light L 2  at the interface F 2 , reflected light L 3  at the interface F 3 , reflected light L 4  at the interface F 4 , and reflected light L 5  at the interface F 5 . 
     Further, by causing the thickness of the insulating film  222  to be thicker than the thickness of the first electrode  261 , the dielectric layer  263 , the second electrode  262 , or the light-shielding film  244 , the optical path length can be increased and the light reaching the light-shielding film  244  can be weaken. Further, by causing the refractive index of the insulating film  222  to be smaller than the refractive index of the second electrode  262 , the light reaching the light-shielding film  244  can be weakened at the interface F 4 . Note that, even when the insulating film  222  is formed to be thick, occurrence of cracks and the like can be suppressed as compared with the light-shielding film  244 . 
     The amount of the reflected light L 5  at the interface F 5  is greater than the amount of the reflected light L 2  at the interface F 2 . That is, the interfacial reflection at the insulating film  222  side of the light-shielding film  244  is greater than the interfacial reflection at the dielectric layer  263  side of the first electrode  261  with respect to the light LL incident from the first substrate  21 . The light is reflected at the interface F 2  in addition to the reflection at the interface F 5 , so that the reflectance and an OD (Optical Density) value of the light LL in the layer below the transistor  23  can be increased as compared with the case where the interface F 2  is not present. Accordingly, as compared with the case where only the light-shielding film  244  is provided in the layer below the transistor  23 , the light-shielding film  244  and the capacitance element  26  are provided in the layer below the transistor  23 , so that the light-shielding properties with respect to the transistor  23  can be improved without excessively thickening the light-shielding film  244 . 
     Further, the capacitance element  26  and the insulating film  222  function as a part of a reflection enhancing film. Specifically, the interface F 4  between the capacitance element  26  and the insulating film  222 , and the interface F 5  between the insulating film  222  and the light-shielding film  244  have reflection enhancing properties. More specifically, the reflection at the interface F 4  and the reflection at the interface F 5  are set to intensify each other. In other words, the insulating film  222  is configured such that the interfacial reflection at the second electrode  262  side and the interfacial reflection at the light-shielding film  244  side intensify each other with respect to the light LL incident from the first substrate  21 . 
     The reflected light L 4  at the interface F 4  and the reflected light L 5  at the interface F 5  are set to intensify each other, so that the light amounts of the reflected light L 4  and the reflected light L 5  are combined. Therefore, the reflectance and the OD value of the light LL in the layer below the transistor  23  can be increased. Accordingly, as compared with the case where only the light-shielding film  244  is provided in the layer below the transistor  23 , the light-shielding film  244 , the capacitance element  26 , and the insulating film  222  are provided in the layer below the transistor  23 , so that the light-shielding properties with respect to the transistor  23  can be improved without excessively thickening the light-shielding film  244 . As a result, the possibility of cracking in the insulating film  222  and the like can be suppressed, and also the light-shielding properties with respect to the transistor  23  can be improved. Therefore, according to the electro-optical device  100 , a new measure capable of improving the light-shielding property of the transistor  23  with respect to the light LL incident from the first substrate  21  as compared with the conventional case while suppressing the occurrence of cracks can be provided. Therefore, display defects such as luminance unevenness of the pixels and the like can be suppressed, and thus deterioration of the display quality of the electro-optical device  100  can be suppressed. 
     By adjusting a thickness d 1  of the insulating film  222  according to a wavelength A of the light LL incident on the first substrate  21 , the reflection at the interface F 4  and the reflection at the interface F 5  are set to intensify each other. Specifically, the thickness d 1  of the insulating film  222  may satisfy the following equation (1). 
         d 1={(½+ m )×λ}/2× n 1  (1)
 
     In the equation (1), m is 0 or a natural number, A is the wavelength of the light LL incident from the first substrate  21 , and n 1  is the refractive index of the insulating film  222 . 
       FIG. 6  is a table illustrating an example of the thickness d 1  of the insulating film  222  illustrated in  FIG. 5 . For example, when the wavelength A is 550 nm and the refractive index n 1  of the insulating film  222  is 1.46, the thickness d 1  [nm] shown in Table 1 of  FIG. 6  is calculated by using the equation (1). 
     When the thickness d 1  satisfies the equation (1), the reflection at the interface F 4  and the reflection at the interface F 5  are set to intensify each other, so that the amount of light reflected in the layer below the transistor  23  can be increased. Therefore, the light-shielding properties with respect to the transistor  23  can be effectively improved. 
     Further, the reflected light L 1  at the interface F 1  and the reflected light L 4  at the interface F 4  are set to intensify each other. In other words, the first electrode  261  and the second electrode  262  are configured such that the interfacial reflection at the first substrate  21  side of the first electrode  261  and the interfacial reflection at the insulating film  222  side of the second electrode  262  intensify each other with respect to the light LL incident from the first substrate  21 . With this configuration, the amount of light of the reflected light L 1  and the reflected light L 4  is combined, and as a result, the reflectance and the OD value of the light LL in the layer below the transistor  23  can be increased. 
     By adjusting a total thickness d 2  of the first electrode  261  and the second electrode  262  according to the wavelength A of the light LL incident on the first substrate  21 , the reflection at the interface F 1  and the reflection at the interface F 4  are set to intensify each other. Specifically, the total thickness d 2  may satisfy the following equation (2). 
         d 2={(½+ m )×λ—2× n 3× d 3}/2× n 2  (2)
 
     In the equation (2), m is 0 or a natural number, A is the wavelength of the light LL incident from the first substrate  21 , n 2  is the refractive index of the first electrode  261  or the second electrode  262 , n 3  is the refractive index of the dielectric layer  263 , and d 3  is the thickness of the dielectric layer  263 . 
       FIG. 7  is a table illustrating an example of the total thickness d 2  of the first electrode  261  and the second electrode  262  illustrated in  FIG. 5 . For example, when the wavelength A is 550 nm, the refractive index n 2  of each of the first electrode  261  and the second electrode  262  is 4.11, the refractive index n 3  of the dielectric layer  263  is 1.9, and the thickness d 3  of the dielectric layer  263  is 19 nm, the total thickness d 2  shown in Table 2 in  FIG. 7  is calculated by using the equation (2). 
     When the total thickness d 2  satisfies the equation (2), the reflection at the interface F 1  and the reflection at the interface F 4  are set to intensify each other, so that the amount of light reflected in the layer below the transistor  23  can be increased. Therefore, the light shielding properties with respect to the transistor  23  can be effectively improved. 
     Further, in order to further improve the light-shielding property with respect to the transistor  23 , the total thickness d 2  of the first electrode  261  and the second electrode  262  and the thickness d 1  of the insulating film  222  are more preferably set such that the reflected light L 1 , L 4  and L 5  intensify each other. 
     Furthermore, it is most preferable that the reflected light L 1  to L 5  are set so as to intensify each other. Accordingly, it is most preferable that a thickness d 21  of the first electrode  261 , the thickness d 3  of the dielectric layer  263 , the thickness d 22  of the second electrode  262 , the thickness d 1  of the insulating film  222 , and the thickness d 4  of the light-shielding film  244  are set such that the reflected light L 1  to L 5  intensify each other. As a result, the light-shielding properties with respect to the transistor  23  can be most effectively improved. However, the dielectric layer  263  depends on the withstand voltage of the electrostatic capacitance of the capacitance element  26 . Therefore, substantially, by adjusting the total thickness d 2  of the first electrode  261  and the second electrode  262 , the thickness d 1  of the insulating film  222 , and the thickness d 4  of the light-shielding film  244 , the light-shielding property with respect to the transistor  23  can be most effectively improved. 
     Further, although the plan view is omitted, the transistor  23 , the light-shielding film  244 , and the capacitance element  26  overlap each other in plan view. Therefore, light incident on the transistor  23  can be effectively suppressed by the light-shielding film  244  and the capacitance element  26 . 
     Further, by setting the materials of the capacitance element  26  and the insulating film  222 , the reflection enhancing property of the capacitance element  26  and the insulating film  222  can be increased. 
     Specifically, examples of each material of the first electrode  261  and the second electrode  262  include a thin film material such as titanium, polysilicon, or the like. Of these, the first electrode  261  and the second electrode  262  may include polysilicon. Note that the polysilicon contains an impurity such as phosphorus (P). Further, as the dielectric layer  263 , silicon nitride, silicon oxide, and the like are used. Furthermore, for example, aluminum oxide, hafnium oxide, or a multilayer film in which these metal oxide films and metal nitride films are layered is used. 
     When the first electrode  261  and the second electrode  262  include polysilicon, heat resistance can be easily improved as compared with the case where the first electrode  261  and the second electrode  262  include metal materials. Therefore, during manufacturing, occurrence of defects such as cracks in the insulating film  222  and the like can be suppressed. Furthermore, occurrence of film peeling of the first electrode  261  and the second electrode  262  can be reduced. 
     The insulating film  222  may include an inorganic material containing silicon such as silicon oxide and silicon oxynitride, and more preferably contains silicon oxide. When the insulating film  222  includes an inorganic material containing silicon, it is possible to suppress occurrence of defects such as cracks in the insulating film  222  and the like during manufacturing, when the second electrode  262  is polysilicon. 
     Examples of the material of the light-shielding film  244  include a metal material as described above. Of these, the light-shielding film  244  may include tungsten silicide. When the light-shielding film  244  includes tungsten silicide, it is easy to set the difference in refractive index between the light-shielding film  244  and the insulating film  222  to a desired value without excessively increasing the thickness d 4  of the light-shielding film  24 , when the insulating film  222  is a material including silicon. Further, since it is not necessary to excessively thicken the thickness d 4 , cracks do not easily occur in the insulating film  222  or the like even due to heat during manufacturing. 
     As described above, the thickness of each layer is set according to the wavelength A of the light LL incident from the first substrate  21 . For example, examples in which the thickness of each layer is set according to the light in the green wavelength region is described below. In the first example in this case, the thickness d 21  of the first electrode  261  is approximately 113 nm, the thickness d 22  of the second electrode  262  is approximately 45 nm, the thickness d 3  of the dielectric layer  263  is approximately 19 nm, the thickness d 1  of the insulating film  222  is about 465 nm, and the thickness d 4  of the light-shielding film  244  is approximately 200 nm. Further, in the second example, for example, the thickness d 21  is approximately 45 nm, the thickness d 22  is approximately 45 nm, the thickness d 3  is approximately 19 nm, the thickness d 1  is approximately 278 nm, and the thickness d 4  is approximately 200 nm. With such a thickness, the reflectance and the OD value of the light LL in the layer below the transistor  23  can be increased. 
     Note that the first example and the second example are examples in which at least the reflected light L 1 , L 4 , and L 5  are set to intensify each other. Further, the first example and the second example satisfy the equations (1) and (2). Furthermore, in the first example and the second example, the materials of the first electrode  261  and the second electrode  262  are polysilicon, the material of the dielectric layer  263  is silicon nitride, the material of the insulating film  222  is silicon oxide, and the material of the light-shielding film  244  is tungsten silicide. 
       FIG. 8  is a diagram illustrating the reflectance in the green wavelength region.  FIG. 8  illustrates simulation results of the reflectance from the first substrate  21  to the layer below the transistor  23 .  FIG. 9  is a diagram illustrating the OD value in the green wavelength region.  FIG. 9  illustrates simulation results of the OD value from the first substrate  21  to the layer below the transistor  23 . Two-dot chain lines illustrated in  FIGS. 8 and 9  are the reflectance or the OD value when the capacitance element  26  and the insulating film  222  are not present between the first substrate  21  and the light-shielding film  244 . Solid lines illustrate the reflectance or the OD value of the first example. Dashed lines illustrate the reflectance or the OD value of the second example. In both results, the materials are the same, only the thickness is varied. Further, the green wavelength region is specifically a wavelength region within a range from 500 nm to 580 nm. 
     As illustrated in  FIGS. 8 and 9 , since the predetermined capacitance element  26 , insulating film  222 , and light-shielding film  244  are present, the reflectance and the OD value in the green wavelength region can be significantly increased as compared with a case where only the scanning line  241  is present. 
     Note that the above example is an example, and other examples can be considered for each thickness. Further, although not illustrated, also in the red wavelength region, that is, the wavelength region in a range from more than 580 nm to 700 nm, the reflectance and the OD value can be increased by setting the thickness according to the wavelength A of the red wavelength region. Similarly, also in the blue wavelength region, that is, the wavelength region in a range from 400 nm to less than 500 nm, the reflectance and the OD value can be increased by setting the thickness according to the wavelength A of the blue wavelength region. 
     2. Modified Example 
     The embodiment exemplified above can be variously modified. Specific modification aspects applied to the embodiment described above are exemplified below. Two or more modes freely selected from exemplifications below can be appropriately used in combination as long as mutual contradiction does not arise. 
     In each of the above-described embodiments, the active matrix system electro-optical device  100  is exemplified, but it is not limited thereto, and the driving system of the electro-optical device  100  may be a passive matrix system or the like, for example. 
     The driving system of the “electro-optical device” is not limited to a vertical electric field system, and may be a transverse electric field system. Examples of the transverse electric field system include, for example, an IPS (In Plane Switching) mode. Furthermore, examples of the vertical electric field system include a TN (Twisted Nematic) mode, a VA (Vertical Alignment) mode, a PVA mode, and an OCB (Optically Compensated Bend) mode. 
     3. Electronic Apparatus 
     The electro-optical device  100  can be used for various electronic apparatuses. 
       FIG. 10  is a perspective view illustrating a personal computer  2000  as an example of an electronic apparatus. The personal computer  2000  includes the electro-optical device  100  configured to display various images, a main body portion  2010  in which a power source switch  2001  and a keyboard  2002  are installed, and a control unit  2003 . The control unit  2003  includes, for example, a processor and a memory, and controls the operation of the electro-optical device  100 . 
       FIG. 11  is a plan view illustrating a smart phone  3000  as an example of the electronic apparatus. The smart phone  3000  includes an operation button  3001 , the electro-optical device  100  configured to display various images, and a control unit  3002 . Screen contents displayed on the electro-optical device  100  are changed according to the operation of the operation button  3001 . The control unit  3002  includes, for example, a processor and a memory, and controls the operation of the electro-optical device  100 . 
       FIG. 12  is a schematic diagram illustrating a projector as an example of the electronic apparatus. The projection-type display device  4000  is a three-plate type projector, for example. An electro-optical device  1   r  is an electro-optical device  100  corresponding to a red display color, an electro-optical device  1   g  is an electro-optical device  100  corresponding to a green display color, and an electro-optical device  1   b  is an electro-optical device  100  corresponding to a blue display color. Specifically, the projection-type display device  4000  includes three electro-optical devices  1   r ,  1   g , and  1   b  that respectively correspond to display colors of red, green, and blue. The control unit  4005  includes, for example, a processor and a memory, and controls the operation of the electro-optical device  100 . 
     An illumination optical system  4001  supplies a red component r of light emitted from an illumination device  4002  as a light source to the electro-optical device  1   r , a green component g of the light to the electro-optical device  1   g , and a blue component b of the light to the electro-optical device  1   b . Each of the electro-optical devices  1   r ,  1   g , and  1   b  functions as an optical modulator, such as a light bulb, that modulates respective rays of the monochromatic light supplied from the illumination optical system  4001  depending on display images. A projection optical system  4003  combines the rays of the light emitted from each of the electro-optical devices  1   r ,  1   g , and  1   b  to project the combined light to a projection surface  4004 . 
     The above electronic apparatus includes the above-described electro-optical device  100  and the control unit  2003 ,  3002 , or  4005 . As described above, the electro-optical device  100  has excellent light-shielding properties with respect to the transistor  23 , thereby suppressing display defects such as pixel luminance unevenness. Accordingly, by providing the electro-optical device  100 , the display quality of the personal computer  2000 , the smart phone  3000 , or the projection-type display apparatus  4000  can be improved. 
     Examples of the electronic apparatus to which the electro-optical device of the present disclosure is applied is not limited to the exemplified apparatus, and include, for example, a Personal Digital Assistant(PDA), a digital still camera, a television, a video camera, a car navigation device, a display device for in-vehicle use, an electronic organizer, an electronic paper, an electronic calculator, a word processor, a workstation, a visual telephone, a POS (Point of Sale) terminal, and the like. Further, the examples of the electronic apparatus to which the present disclosure is applied include a device including a printer, a scanner, a copier, a video player, and a touch panel. 
     The present disclosure has been described above based on the preferred embodiment, but the present disclosure is not limited to the embodiment described above. In addition, the configuration of each component of the present disclosure may be replaced with any configuration that exerts the equivalent functions of the above-described embodiments, and to which any configuration may be added. 
     Further, in the description described above, a liquid crystal display device is described as an example of the electro-optical device of the present disclosure, but the electro-optical device of the present disclosure is not limited thereto. For example, the electro-optical device of the present disclosure can also be applied to an image sensor or the like.