Patent Publication Number: US-2021181485-A1

Title: Wide-angle lens

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     The present invention claims priority under 35 U.S.C. § 119 to Chinese Application No. 201911281965.1 filed on Dec. 13, 2019, the entire content of which is incorporated herein by reference. 
     FIELD OF THE INVENTION 
     The disclosure relates to a wide-angle lens. 
     BACKGROUND 
     As a lens mounted in an in-vehicle camera or the like, there has conventionally been a wide-angle lens including, sequentially arranged from an object side, a first lens, a second lens, a third lens, a fourth lens, a diaphragm, a fifth lens, a sixth lens and a seventh lens. Among them, the sixth lens and the seventh lens constitute a cemented lens. 
     In practice, it is sometimes necessary to reduce the size of the in-vehicle camera equipped with the above-mentioned wide-angle lens, and in that case, the wide-angle lens needs to be miniaturized. However, the miniaturization of the wide-angle lens may reduce a maximum half field of view (HFOV) of the in-vehicle camera. 
     SUMMARY 
     An exemplary embodiment of the disclosure provides a wide-angle lens, including a lens group and a diaphragm. Multiple lenses in the lens group are sequentially arranged from an object side in a manner sandwiching the diaphragm. A maximum half field of view of the wide-angle lens as a whole is set to ω, 98°&lt;ω&lt;120° is satisfied. An effective focal length of the wide-angle lens as a whole is set to f, and an entrance pupil diameter of the wide-angle lens as a whole is set to HEP, f/HEP&lt;2.3 is satisfied. The lens group includes a first lens that is located closest to the object side and that is a negative lens with a concave surface facing an image side. An effective radius of an image side lens surface of the first lens is set to sd12, and a radius of curvature of the image side lens surface of the first lens is set to R12, 0.890&lt;sd12/R12&lt;0.970 is satisfied. 
     The above and other elements, features, steps, characteristics and advantages of the present disclosure will become more apparent from the following detailed description of the preferred embodiments with reference to the attached drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  illustrates a wide-angle lens according to Embodiment 1 of the disclosure. 
         FIG. 2A  illustrates curvature of field and distortion of the wide-angle lens according to Embodiment 1 of the disclosure. 
         FIG. 2B  illustrates curvature of field and distortion of the wide-angle lens according to Embodiment 1 of the disclosure. 
         FIG. 3A  illustrates lateral chromatic aberration (transverse chromatic aberration) of the wide-angle lens according to Embodiment 1 of the disclosure. 
         FIG. 3B  illustrates spherical aberration (longitudinal aberration) of the wide-angle lens according to Embodiment 1 of the disclosure. 
         FIG. 4A  to  FIG. 4L  illustrate transverse aberration of the wide-angle lens according to Embodiment 1 of the disclosure. 
         FIG. 5  illustrates a wide-angle lens according to Embodiment 2 of the disclosure. 
         FIG. 6A  illustrates curvature of field and distortion of the wide-angle lens according to Embodiment 2 of the disclosure. 
         FIG. 6B  illustrates curvature of field and distortion of the wide-angle lens according to Embodiment 2 of the disclosure. 
         FIG. 7A  illustrates lateral chromatic aberration (transverse chromatic aberration) of the wide-angle lens according to Embodiment 2 of the disclosure. 
         FIG. 7B  illustrates spherical aberration (longitudinal aberration) of the wide-angle lens according to Embodiment 2 of the disclosure. 
         FIG. 8A  to  FIG. 8L  illustrate transverse aberration of the wide-angle lens according to Embodiment 2 of the disclosure. 
         FIG. 9  illustrates a wide-angle lens according to Embodiment 3 of the disclosure. 
         FIG. 10A  illustrates curvature of field and distortion of the wide-angle lens according to Embodiment 3 of the disclosure. 
         FIG. 10B  illustrates curvature of field and distortion of the wide-angle lens according to Embodiment 3 of the disclosure. 
         FIG. 11A  illustrates lateral chromatic aberration (transverse chromatic aberration) of the wide-angle lens according to Embodiment 3 of the disclosure. 
         FIG. 11B  illustrates spherical aberration (longitudinal aberration) of the wide-angle lens according to Embodiment 3 of the disclosure. 
         FIG. 12A  to  FIG. 12L  illustrate transverse aberration of the wide-angle lens according to Embodiment 3 of the disclosure. 
         FIG. 13  illustrates a wide-angle lens according to Embodiment 4 of the disclosure. 
         FIG. 14A  illustrates curvature of field and distortion of the wide-angle lens according to Embodiment 4 of the disclosure. 
         FIG. 14B  illustrates curvature of field and distortion of the wide-angle lens according to Embodiment 4 of the disclosure. 
         FIG. 15A  illustrates lateral chromatic aberration (transverse chromatic aberration) of the wide-angle lens according to Embodiment 4 of the disclosure. 
         FIG. 15B  illustrates spherical aberration (longitudinal aberration) of the wide-angle lens according to Embodiment 4 of the disclosure. 
         FIG. 16A  to  FIG. 16L  illustrate transverse aberration of the wide-angle lens according to Embodiment 4 of the disclosure. 
         FIG. 17  illustrates a wide-angle lens according to Embodiment 5 of the disclosure. 
         FIG. 18A  illustrates curvature of field and distortion of the wide-angle lens according to Embodiment 5 of the disclosure. 
         FIG. 18B  illustrates curvature of field and distortion of the wide-angle lens according to Embodiment 5 of the disclosure. 
         FIG. 19A  illustrates lateral chromatic aberration (transverse chromatic aberration) of the wide-angle lens according to Embodiment 5 of the disclosure. 
         FIG. 19B  illustrates spherical aberration (longitudinal aberration) of the wide-angle lens according to Embodiment 5 of the disclosure. 
         FIG. 20A  to  FIG. 20L  illustrate transverse aberration of the wide-angle lens according to Embodiment 5 of the disclosure. 
         FIG. 21  illustrates a wide-angle lens according to Embodiment 6 of the disclosure. 
         FIG. 22A  illustrates curvature of field and distortion of the wide-angle lens according to Embodiment 6 of the disclosure. 
         FIG. 22B  illustrates curvature of field and distortion of the wide-angle lens according to Embodiment 6 of the disclosure. 
         FIG. 23A  illustrates lateral chromatic aberration (transverse chromatic aberration) of the wide-angle lens according to Embodiment 6 of the disclosure. 
         FIG. 23B  illustrates spherical aberration (longitudinal aberration) of the wide-angle lens according to Embodiment 6 of the disclosure. 
         FIG. 24A  to  FIG. 24L  illustrate transverse aberration of the wide-angle lens according to Embodiment 6 of the disclosure. 
         FIG. 25  illustrates a wide-angle lens according to Embodiment 7 of the disclosure. 
         FIG. 26A  illustrates curvature of field and distortion of the wide-angle lens according to Embodiment 7 of the disclosure. 
         FIG. 26B  illustrates curvature of field and distortion of the wide-angle lens according to Embodiment 7 of the disclosure. 
         FIG. 27A  illustrates lateral chromatic aberration (transverse chromatic aberration) of the wide-angle lens according to Embodiment 7 of the disclosure. 
         FIG. 27B  illustrates spherical aberration (longitudinal aberration) of the wide-angle lens according to Embodiment 7 of the disclosure. 
         FIG. 28A  to  FIG. 28L  illustrate transverse aberration of the wide-angle lens according to Embodiment 7 of the disclosure. 
         FIG. 29  illustrates a wide-angle lens according to Embodiment 8 of the disclosure. 
         FIG. 30A  illustrates curvature of field and distortion of the wide-angle lens according to Embodiment 8 of the disclosure. 
         FIG. 30B  illustrates curvature of field and distortion of the wide-angle lens according to Embodiment 8 of the disclosure. 
         FIG. 31A  illustrates lateral chromatic aberration (transverse chromatic aberration) of the wide-angle lens according to Embodiment 8 of the disclosure. 
         FIG. 31B  illustrates spherical aberration (longitudinal aberration) of the wide-angle lens according to Embodiment 8 of the disclosure. 
         FIG. 32A  to  FIG. 32L  illustrate transverse aberration of the wide-angle lens according to Embodiment 8 of the disclosure. 
         FIG. 33  illustrates a wide-angle lens according to Embodiment 9 of the disclosure. 
         FIG. 34A  illustrates curvature of field and distortion of the wide-angle lens according to Embodiment 9 of the disclosure. 
         FIG. 34B  illustrates curvature of field and distortion of the wide-angle lens according to Embodiment 9 of the disclosure. 
         FIG. 35A  illustrates lateral chromatic aberration (transverse chromatic aberration) of the wide-angle lens according to Embodiment 9 of the disclosure. 
         FIG. 35B  illustrates spherical aberration (longitudinal aberration) of the wide-angle lens according to Embodiment 9 of the disclosure. 
         FIG. 36A  to  FIG. 36L  illustrate transverse aberration of the wide-angle lens according to Embodiment 9 of the disclosure. 
     
    
    
     DETAILED DESCRIPTION 
     Hereinafter, each embodiment of a wide-angle lens of the disclosure will be described with reference to the accompanying drawings. In the following description, in an extension direction of an optical axis L, an object side is denoted by L 1 , and an image side is denoted by L 2 . 
       FIG. 1  illustrates a wide-angle lens according to Embodiment 1 of the disclosure.  FIG. 2A  illustrates curvature of field and distortion of the wide-angle lens according to Embodiment 1 of the disclosure.  FIG. 2B  illustrates curvature of field and distortion of the wide-angle lens according to Embodiment 1 of the disclosure.  FIG. 3A  illustrates lateral chromatic aberration (transverse chromatic aberration) of the wide-angle lens according to Embodiment 1 of the disclosure.  FIG. 3B  illustrates spherical aberration (longitudinal aberration) of the wide-angle lens according to Embodiment 1 of the disclosure.  FIG. 4A  to  FIG. 4L  illustrate transverse aberration of the wide-angle lens according to Embodiment 1 of the disclosure. Here, in  FIG. 2A ,  FIG. 2B ,  FIG. 3A ,  FIG. 3B , and  FIG. 4A  to  FIG. 4L , a correlation curve of red light R (having a wavelength of 656 nm) is denoted by R, a correlation curve of green light G (having a wavelength of 588 nm) is denoted by G, and a correlation curve of blue light B (having a wavelength of 486 nm) is denoted by B. T indicates being related to the meridian plane, and S indicates being related to the sagittal plane. Moreover, in  FIG. 4A  to  FIG. 4L , a maximum scale of the longitudinal axis is ±50.000 μm. 
     As shown in  FIG. 1 , a wide-angle lens  1000  includes, sequentially arranged from the object side (L 1  side), a first lens  110  (that is, the first lens  110  is located closest to the object side), a second lens  120  (that is, the second lens  120  is located on the image side of and adjacent to the first lens  110 ), a third lens  130 , a fourth lens  140 , a diaphragm  180 , a fifth lens  150 , a sixth lens  160  and a seventh lens  170 . Among them, the sixth lens  160  and the seventh lens  170  are bonded together by an adhesive to constitute a cemented lens. 
     Here, the first lens  110  is a lens (simply referred to as negative lens) with negative refractive power, having a convex surface (first surface  1 ) facing the object side L 1  and a concave surface (second surface  2 ) facing the image side L 2 . In this embodiment, the first lens  110  is a glass lens in which the first surface  1  and the second surface  2  are spherical surfaces. 
     The second lens  120  is a lens with negative refractive power, having a convex surface (third surface  3 ) facing the object side L 1  and a concave surface (fourth surface  4 ) facing the image side L 2 . In this embodiment, the second lens  120  is a plastic lens in which the third surface  3  and the fourth surface  4  are aspherical surfaces. 
     The third lens  130  is a lens (simply referred to as positive lens) with positive refractive power, having a concave surface (fifth surface  5 ) facing the object side L 1  and a convex surface (sixth surface  6 ) facing the image side L 2 . In this embodiment, the third lens  130  is a plastic lens in which the fifth surface  5  and the sixth surface  6  are aspherical surfaces. 
     The fourth lens  140  is a lens with positive refractive power, having a concave surface (seventh surface  7 ) facing the object side L 1  and a convex surface (eighth surface  8 ) facing the image side L 2 . In this embodiment, the fourth lens  140  is a plastic lens in which the seventh surface  7  and the eighth surface  8  are aspherical surfaces. 
     The fifth lens  150  is a lens with positive refractive power, having a convex surface (tenth surface  10 ) facing the object side L 1  and a convex surface (eleventh surface  11 ) facing the image side L 2 . In this embodiment, the fifth lens  150  is composed of a glass lens. 
     The sixth lens  160  is a lens with negative refractive power, having a concave surface (twelfth surface  12 ) facing the object side L 1  and a concave surface (thirteenth surface  13 ) facing the image side L 2 . The sixth lens  160  constitutes a cemented lens with the seventh lens  170 . In this embodiment, the sixth lens  160  is a plastic lens in which the twelfth surface  12  and the thirteenth surface  13  are aspherical surfaces. 
     The seventh lens  170  is a lens with positive refractive power, having a convex surface (thirteenth surface  13 ) facing the object side L 1  and a convex surface (fourteenth surface  14 ) facing the image side L 2 . In this embodiment, the seventh lens  170  is a plastic lens in which the thirteenth surface  13  and the fourteenth surface  14  are aspherical surfaces. 
     In addition, in this embodiment, as shown in  FIG. 1 , a light-shielding sheet  190  is provided between the second lens  120  and the third lens  130 , a filter  200  is arranged on the image side of the seventh lens  170 , and an imaging element  300  is arranged on the image side of the filter  200 . 
     In this embodiment, in the lens system as a whole, an effective focal length f is 1.023 mm, an object-to-image distance (total track) d is 13.611 mm, an F value (image space F/#) is 2.02, a maximum half field of view (HFOV) (maximum half field angle) is 115 degrees, and an entrance pupil diameter HEP is 0.507 mm. 
     Table 1 shows physical properties of each surface of the wide-angle lens  1000  of this embodiment. Table 2-1 and Table 2-2 show aspheric coefficients of each surface of the wide-angle lens  1000  of this embodiment. 
     
       
         
           
               
               
               
               
               
               
               
               
             
               
                 TABLE 1 
               
               
                   
               
               
                   
                 Radius of 
                   
                   
                   
                 Effective 
                 Effective 
                   
               
               
                 Surface 
                 curvature 
                 Thickness 
                 N d   
                 v d   
                 focal length 
                 radius 
                 Sag 
               
               
                   
               
             
            
               
                   
               
            
           
           
               
               
               
               
               
               
               
               
            
               
                  1 
                 11.420 
                 1.510 
                 1.871 
                 40.73 
                 −1.338 
                 6.456 
                 1.999 
               
               
                  2 
                 3.350 
                 2.050 
                   
                   
                   
                 3.055 
                 1.974 
               
               
                  3* 
                 40.687 
                 0.600 
                 1.544 
                 56.4 
                   
                 2.762 
                 0.051 
               
               
                  4* 
                 1.222 
                 1.427 
                   
                   
                   
                 1.461 
                 1.176 
               
               
                  5* 
                 −11.789 
                 0.689 
                 1.544 
                 56.4 
                 3.122 
                 1.396 
                 −0.028 
               
               
                  6* 
                 −2.855 
                 0.597 
                   
                   
                   
                 1.268 
                 −0.123 
               
               
                  7* 
                 −13.315 
                 0.778 
                 1.635 
                 23.9 
                   
                 1.068 
                 0.060 
               
               
                  8* 
                 −2.589 
                 −0.039 
                   
                   
                   
                 0.890 
                 −0.121 
               
               
                  9 
                 Infinite 
                 0.257 
               
               
                 (diaphragm) 
               
               
                 10 
                 15.150 
                 1.288 
                 1.697 
                 55.46 
                   
                 1.400 
                 0.065 
               
               
                 11 
                 −2.501 
                 0.101 
                   
                   
                   
                 1.400 
                 −0.428 
               
               
                 12* 
                 −5.143 
                 0.500 
                 1.635 
                 23.9 
                 13.449 
                 1.180 
                 −0.158 
               
               
                 13* 
                 1.018 
                 2.362 
                 1.544 
                 56.4 
                   
                 1.458 
                 1.199 
               
               
                 14* 
                 −2.561 
                 0.965 
                   
                   
                   
                 1.657 
                 −0.456 
               
               
                 15 
                 Infinite 
                 0.400 
               
               
                 16 
                 Infinite 
                 0.125 
               
               
                   
               
            
           
         
       
     
     In Table 1 above, the radius of curvature, thickness, effective focal length, effective radius, and sag are in units of mm. N d  represents a refractive index for a ray of 587.56 nm. V d  represents the Abbe number. * represents an aspheric surface. 
     
       
         
           
               
               
               
               
               
             
               
                 TABLE 2-1 
               
               
                   
               
               
                 Surface 
                 c (1/radius of curvature) 
                 K 
                 A4 
                 A6 
               
               
                   
               
             
            
               
                   
               
            
           
           
               
               
               
               
               
            
               
                 3 
                  2.45778E−02 
                 0.00000E+00 
                 −7.34647E−04  
                 0.00000E+00 
               
               
                 4 
                  8.18649E−01 
                 −1.00000E+00  
                 3.34909E−02 
                 1.52429E−02 
               
               
                 5 
                 −8.48284E−02 
                 0.00000E+00 
                 −1.05901E−02  
                 2.28744E−02 
               
               
                 6 
                 −3.50286E−01 
                 0.00000E+00 
                 4.60516E−02 
                 1.35719E−02 
               
               
                 7 
                 −7.51052E−02 
                 0.00000E+00 
                 6.96916E−02 
                 5.26973E−04 
               
               
                 8 
                 −3.86206E−01 
                 0.00000E+00 
                 4.85130E−02 
                 1.07658E−02 
               
               
                 12 
                 −1.94439E−01 
                 0.00000E+00 
                 1.37213E−02 
                 −3.80723E−02  
               
               
                 13 
                  9.82404E−01 
                 −1.00000E+00  
                 2.47704E−01 
                 −2.97167E−01  
               
               
                 14 
                 −3.90445E−01 
                 0.00000E+00 
                 2.43790E−02 
                 −1.73998E−02  
               
               
                   
               
            
           
         
       
     
     
       
         
           
               
               
               
               
               
               
             
               
                 TABLE 2-2 
               
               
                   
               
               
                 Surface 
                 A8 
                 A10 
                 A12 
                 A14 
                 A16 
               
               
                   
               
             
            
               
                   
               
            
           
           
               
               
               
               
               
               
            
               
                 3 
                 0.00000E+00 
                 0.00000E+00 
                 0.00000E+00 
                 0.00000E+00 
                 0.00000E+00 
               
               
                 4 
                 −3.29328E−03  
                 2.82298E−03 
                 −4.88754E−04  
                 0.00000E+00 
                 0.00000E+00 
               
               
                 5 
                 −5.12306E−03  
                 0.00000E+00 
                 0.00000E+00 
                 0.00000E+00 
                 0.00000E+00 
               
               
                 6 
                 0.00000E+00 
                 0.00000E+00 
                 0.00000E+00 
                 0.00000E+00 
                 0.00000E+00 
               
               
                 7 
                 4.37857E−03 
                 2.92148E−03 
                 0.00000E+00 
                 0.00000E+00 
                 0.00000E+00 
               
               
                 8 
                 −5.94177E−03  
                 1.11565E−02 
                 0.00000E+00 
                 0.00000E+00 
                 0.00000E+00 
               
               
                 12 
                 1.79956E−02 
                 −7.87537E−04  
                 −1.30556E−03  
                 0.00000E+00 
                 0.00000E+00 
               
               
                 13 
                 1.73181E−01 
                 −4.77496E−02  
                 4.65741E−03 
                 0.00000E+00 
                 0.00000E+00 
               
               
                 14 
                 1.34046E−02 
                 −4.35536E−03  
                 5.73510E−04 
                 0.00000E+00 
                 0.00000E+00 
               
               
                   
               
            
           
         
       
     
     In Table 2-1 and Table 2-2 above, in a case where a lens surface is a convex surface protruding toward the object side or a concave surface recessed toward the object side, its radius of curvature is set to a positive value; in a case where a lens surface is a convex surface protruding toward the image side or a concave surface recessed toward the image side, its radius of curvature is set to a negative value. 
     In addition, Table 2-1 and Table 2-2 above show the aspheric coefficients A4, A6, A8, A10, A12, A14 and A16 of each of the aspheric surfaces, which satisfy the following expression 1. In the following expression, Z represents sag (axis in an optical axis direction), r represents height (ray height) in a direction perpendicular to the optical axis, K represents the conic coefficient, and c represents the reciprocal of the radius of curvature. 
     
       
         
           
             
               
                 
                   Z 
                   = 
                   
                     
                       
                         c 
                          
                         
                           r 
                           2 
                         
                       
                       
                         1 
                         + 
                         
                           
                             1 
                             - 
                             
                               
                                 ( 
                                 
                                   1 
                                   + 
                                   K 
                                 
                                 ) 
                               
                                
                               
                                 c 
                                 2 
                               
                                
                               
                                 r 
                                 2 
                               
                             
                           
                         
                       
                     
                     + 
                     
                       
                         ∑ 
                         
                           n 
                           = 
                           2 
                         
                         5 
                       
                        
                       
                         
                           A 
                           
                             2 
                              
                             n 
                           
                         
                          
                         
                           r 
                           
                             2 
                              
                             n 
                           
                         
                       
                     
                   
                 
               
               
                 
                   [ 
                   
                     Expression 
                      
                     
                         
                     
                      
                     1 
                   
                   ] 
                 
               
             
           
         
       
     
     Here, as described above, the maximum HFOV co of the wide-angle lens  1000  as a whole is 115 degrees, that is, the following condition 1-1 is satisfied: 
       98°&lt;ω&lt;120°  (1-1)
 
     In condition 1-1, the maximum HFOV co is set to be greater than 98°, thereby expanding the maximum HFOV ω; the maximum HFOV co is set to be less than 120°, thereby avoiding a situation that a peripheral portion of an image becomes dark due to a light quantity ratio at the periphery of the wide-angle lens  1000  being smaller than a light quantity ratio at the center of the wide-angle lens  1000 . Further, the wide-angle lens  1000  is able to be miniaturized as a whole while the maximum HFOV co of the wide-angle lens  1000  is expanded. 
     In addition, in the wide-angle lens  1000  as a whole, the effective focal length f is 1.023 mm and the entrance pupil diameter HEP is 0.507 mm. Therefore, the following condition 1-2 is satisfied: 
         f/HEP&lt; 2.3  (1-2)
 
     In condition 1-2, a ratio of the effective focal length f to the entrance pupil diameter HEP of the wide-angle lens  1000  as a whole is set as f/HEP&lt;2.3, thereby ensuring the brightness of the wide-angle lens  1000 , and enabling use of the wide-angle lens  1000  in a high pixel imaging element. 
     In addition, as is clear from Table 1, an effective radius sd12 of an image side lens surface (that is, the second surface  2 ) of the first lens  110  is 3.055 mm, and a radius of curvature R12 of the second surface  2  of the first lens  110  is 3.350 mm. Therefore, the following condition 1-3 is satisfied: 
       0.890&lt; sd 12/ R 12&lt;0.970  (1-3)
 
     In condition 1-3, a ratio of the effective radius sd12 to the radius of curvature R12 of the second surface  2  of the first lens  110  is set to be greater than 0.890, thereby expanding the HFOV, in particular, to 98° or greater; the ratio of the effective radius sd12 to the radius of curvature R12 of the second surface  2  of the first lens  110  is set to be less than 0.970, thereby preventing an angle defined between a peripheral part of the second surface  2  of the first lens  110  made of glass and a tangent line from being excessively small, and further making it possible to perform a polishing process on the second surface  2  of the first lens  110 . 
     In addition, as is clear from Table 1, a radius of curvature R11 of an object side lens surface (that is, the first surface  1 ) of the first lens  110  is 11.420 mm, and the radius of curvature R12 of the image side lens surface (that is, the second surface  2 ) of the first lens  110  is 3.350 mm. Therefore, the following condition 1-4 is satisfied: 
       1.300&lt;( R 11+ R 12)/( R 11− R 12)&lt;1.900  (1-4)
 
     Moreover, the following condition 1-5 is satisfied: 
       1.600&lt;( R 11+ R 12)/( R 11− R 12)&lt;1.850  (1-5)
 
     In condition 1-4, (R11+R12)/(R11−R12) is set to be greater than 1.300, thereby preventing the radius of curvature R12 of the image side lens surface (that is, the second surface  2 ) of the first lens  110  from being excessively small, thus facilitating the molding of the second surface  2  of the first lens  110 . In another respect, the radius of curvature R11 of the object side lens surface (that is, the first surface  1 ) of the first lens  110  is able to be prevented from being excessively large, thereby avoiding an excessively large diameter of the first lens  110 , thus miniaturizing the wide-angle lens  1000 . In addition, (R11+R12)/(R11−R12) is set to be less than 1.900, thereby ensuring sufficient refractive power of the first lens  110 , thus facilitating the expansion of the maximum HFOV co of the first lens  110 . Moreover, a sufficient thickness of the first lens  110  is able to be ensured, so as to prevent the first lens  110  from being damaged due to impact or the like. 
     In condition 1-5, (R11+R12)/(R11−R12) is further set to be greater than 1.600, thereby further preventing the radius of curvature R12 of the image side lens surface (that is, the second surface  2 ) of the first lens  110  from being excessively small, thus further facilitating the molding of the second surface  2  of the first lens  110 . In another respect, the radius of curvature R11 of the object side lens surface (that is, the first surface  1 ) of the first lens  110  is able to be further prevented from being excessively large, thereby further avoiding an excessively large diameter of the first lens  110 , thus further miniaturizing the wide-angle lens  1000 . In addition, (R11+R12)/(R11−R12) is further set to be less than 1.850, thereby further ensuring sufficient refractive power of the first lens  110 , thus further facilitating the expansion of the maximum HFOV co of the first lens  110 . Moreover, a sufficient thickness of the first lens  110  is able to be further ensured, so as to further prevent the first lens  110  from being damaged due to impact or the like. 
     In addition, as is clear from Table 1, a thickness T1 of the first lens  110  is 1.510 mm (the thickness T1 of the first lens  110  is defined as a distance between the object side lens surface (that is, the first surface  1 ) of the first lens  110  and the image side lens surface (that is, the second surface  2 ) of the first lens  110  in the optical axis direction), a sag Sag12 of the image side lens surface (that is, the second surface  2 ) of the first lens  110  is 1.974 mm. Therefore, the following condition 1-6 is satisfied: 
       0.700&lt; T 1/ Sag 12&lt;1.100  (1-6)
 
     In condition 1-6, a ratio of the thickness T1 of the first lens  110  to the sag Sag12 of the image side lens surface (that is, the second surface  2 ) of the first lens  110  is set to be greater than 0.700, thereby ensuring a sufficient thickness of the first lens  110  to prevent the first lens  110  from being damaged due to impact or the like; the ratio of the thickness T1 of the first lens  110  to the sag Sag12 of the image side lens surface (that is, the second surface  2 ) of the first lens  110  is set to be less than 1.100, thereby avoiding an excessively large thickness of the first lens  110 , thus making it possible to achieve desired negative refractive power. 
     In addition, in the wide-angle lens  1000  of this embodiment, the object-to-image distance d of the wide-angle lens  1000  is 13.611 mm, and the effective focal length f of the wide-angle lens  1000  as a whole is 1.023 mm. Therefore, the following condition 1-7 is satisfied: 
       11.000&lt; d/f&lt; 15.000  (1-7)
 
     In condition 1-7, a ratio of the object-to-image distance d of the wide-angle lens  1000  to the effective focal length f of the wide-angle lens  1000  as a whole is set to be greater than 11.000, thereby enabling appropriate correction to be easily made for various aberrations, thus making it easy to achieve good optical characteristics; the ratio of the object-to-image distance d of the wide-angle lens  1000  to the effective focal length f of the wide-angle lens  1000  as a whole is set to be less than 15.000, thereby preventing the wide-angle lens  1000  from becoming excessively large while avoiding an excessively large overall length of the wide-angle lens  1000 . 
     In summary, in this embodiment, by configuring the wide-angle lens  1000  as above, as shown in  FIG. 2A  to  FIG. 4L , appropriate correction is enabled for various aberrations such as curvature of field, chromatic aberration of magnification, and coma. Moreover, the miniaturization is able to be achieved while the maximum HFOV co is expanded. 
       FIG. 5  illustrates a wide-angle lens according to Embodiment 2 of the disclosure.  FIG. 6A  illustrates curvature of field and distortion of the wide-angle lens according to Embodiment 2 of the disclosure.  FIG. 6B  illustrates curvature of field and distortion of the wide-angle lens according to Embodiment 2 of the disclosure.  FIG. 7A  illustrates lateral chromatic aberration (transverse chromatic aberration) of the wide-angle lens according to Embodiment 2 of the disclosure.  FIG. 7B  illustrates spherical aberration (longitudinal aberration) of the wide-angle lens according to Embodiment 2 of the disclosure.  FIG. 8A  to  FIG. 8L  illustrate transverse aberration of the wide-angle lens according to Embodiment 2 of the disclosure. Here, in  FIG. 6A ,  FIG. 6B ,  FIG. 7A ,  FIG. 7B , and  FIG. 8A  to  FIG. 8L , a correlation curve of red light R (having a wavelength of 656 nm) is denoted by R, a correlation curve of green light G (having a wavelength of 588 nm) is denoted by G, and a correlation curve of blue light B (having a wavelength of 486 nm) is denoted by B. T indicates being related to the meridian plane, and S indicates being related to the sagittal plane. Moreover, in  FIG. 8A  to  FIG. 8L , the maximum scale of the longitudinal axis is ±50.000 μm. 
     As shown in  FIG. 5 , the wide-angle lens  1000  includes, sequentially arranged from the object side (L 1  side), the first lens  110  (that is, the first lens  110  is located closest to the object side), the second lens  120  (that is, the second lens  120  is located on the image side of and adjacent to the first lens  110 ), the third lens  130 , the fourth lens  140 , the diaphragm  180 , the fifth lens  150 , the sixth lens  160  and the seventh lens  170 . Among them, the sixth lens  160  and the seventh lens  170  are bonded together by an adhesive to constitute a cemented lens. 
     Here, the wide-angle lens  1000  in this embodiment has the same basic structure (that is, whether each of the first lens  110 , the second lens  120 , the third lens  130 , the fourth lens  140 , the fifth lens  150 , the sixth lens  160  and the seventh lens  170  has positive refractive power or negative refractive power, whether each of these lenses is a glass lens or plastic lens, whether the object side surface and the image side surface of each of these lenses are convex surfaces or concave surfaces, and whether the object side surface and the image side surface are spherical surfaces or aspheric surfaces) as that of the wide-angle lens of Embodiment 1, and thus the details thereof will be omitted. 
     As shown in  FIG. 5 , similarly to Embodiment 1, the light-shielding sheet  190  is provided between the second lens  120  and the third lens  130 , the filter  200  is arranged on the image side of the seventh lens  170 , and the imaging element  300  is arranged on the image side of the filter  200 . 
     In this embodiment, in the lens system as a whole, the effective focal length f is 1.062 mm, the object-to-image distance (total track) d is 13.610 mm, the F value (image space F/#) is 2.02, the maximum HFOV (maximum half field angle) is 115 degrees, and the entrance pupil diameter HEP is 0.526 mm. 
     Table 3 shows physical properties of each surface of the wide-angle lens  1000  of this embodiment. Table 4-1 and Table 4-2 show aspheric coefficients of each surface of the wide-angle lens  1000  of this embodiment. 
     
       
         
           
               
               
               
               
               
               
               
               
             
               
                 TABLE 3 
               
               
                   
               
               
                   
                 Radius of 
                   
                   
                   
                 Effective 
                 Effective 
                   
               
               
                 Surface 
                 curvature 
                 Thickness 
                 N d   
                 v d   
                 focal length 
                 radius 
                 Sag 
               
               
                   
               
             
            
               
                   
               
            
           
           
               
               
               
               
               
               
               
               
            
               
                  1 
                 11.363 
                 1.561 
                 1.871 
                 40.73 
                 −1.406 
                 6.449 
                 2.009 
               
               
                  2 
                 3.310 
                 2.024 
                   
                   
                   
                 3.013 
                 1.940 
               
               
                  3* 
                 45.562 
                 0.600 
                 1.544 
                 56.4 
                   
                 2.690 
                 0.051 
               
               
                  4* 
                 1.309 
                 1.360 
                   
                   
                   
                 1.418 
                 1.106 
               
               
                  5* 
                 −9.695 
                 0.703 
                 1.544 
                 56.4 
                 3.380 
                 1.353 
                 −0.030 
               
               
                  6* 
                 −2.596 
                 0.565 
                   
                   
                   
                 1.233 
                 −0.136 
               
               
                  7* 
                 −4.818 
                 0.732 
                 1.635 
                 23.9 
                   
                 1.052 
                 −0.022 
               
               
                  8* 
                 −2.244 
                 −0.043 
                   
                   
                   
                 0.917 
                 −0.157 
               
               
                  9 
                 Infinite 
                 0.201 
               
               
                 (diaphragm) 
               
               
                 10 
                 16.738 
                 1.245 
                 1.697 
                 55.46 
                   
                 1.400 
                 0.059 
               
               
                 11 
                 −2.709 
                 0.244 
                   
                   
                   
                 1.400 
                 −0.390 
               
               
                 12* 
                 −6.978 
                 0.500 
                 1.635 
                 23.9 
                 8.893 
                 1.202 
                 −0.115 
               
               
                 13* 
                 1.029 
                 2.426 
                 1.544 
                 56.4 
                   
                 1.478 
                 1.225 
               
               
                 14* 
                 −2.427 
                 0.968 
                   
                   
                   
                 1.679 
                 −0.492 
               
               
                 15 
                 Infinite 
                 0.400 
               
               
                 16 
                 Infinite 
                 0.125 
               
               
                   
               
            
           
         
       
     
     In Table 3 above, the radius of curvature, thickness, effective focal length, effective radius, and sag are in units of mm. N d  represents a refractive index for a ray of 587.56 nm. V d  represents the Abbe number. * represents an aspheric surface. 
     
       
         
           
               
               
               
               
               
             
               
                 TABLE 4-1 
               
               
                   
               
               
                 Surface 
                 c (1/radius of curvature) 
                 K 
                 A4 
                 A6 
               
               
                   
               
             
            
               
                   
               
            
           
           
               
               
               
               
               
            
               
                 3 
                  2.19479E−02 
                 0.00000E+00 
                 −5.53459E−04  
                  0.00000E+00 
               
               
                 4 
                  7.64121E−01 
                 −1.00000E+00  
                 4.76939E−02 
                  1.87020E−03 
               
               
                 5 
                 −1.03144E−01 
                 0.00000E+00 
                 −4.63672E−04  
                  2.39479E−02 
               
               
                 6 
                 −3.85243E−01 
                 0.00000E+00 
                 6.19526E−02 
                  9.41258E−03 
               
               
                 7 
                 −2.07563E−01 
                 0.00000E+00 
                 8.01905E−02 
                 −1.81445E−02 
               
               
                 8 
                 −4.45687E−01 
                 0.00000E+00 
                 5.32792E−02 
                 −3.21513E−03 
               
               
                 12 
                 −1.43308E−01 
                 0.00000E+00 
                 2.59200E−02 
                 −4.54679E−02 
               
               
                 13 
                  9.71678E−01 
                 −1.00000E+00  
                 2.67381E−01 
                 −3.18917E−01 
               
               
                 14 
                 −4.11994E−01 
                 0.00000E+00 
                 2.93182E−02 
                 −2.05884E−02 
               
               
                   
               
            
           
         
       
     
     
       
         
           
               
               
               
               
               
               
             
               
                 TABLE 4-2 
               
               
                   
               
               
                 Surface 
                 A8 
                 A10 
                 A12 
                 A14 
                 A16 
               
               
                   
               
             
            
               
                   
               
            
           
           
               
               
               
               
               
               
            
               
                 3 
                 0.00000E+00 
                  0.00000E+00 
                 0.00000E+00 
                 0.00000E+00 
                 0.00000E+00 
               
               
                 4 
                 1.18832E−02 
                 −3.21383E−03 
                 7.23623E−04 
                 0.00000E+00 
                 0.00000E+00 
               
               
                 5 
                 −7.11892E−03  
                  0.00000E+00 
                 0.00000E+00 
                 0.00000E+00 
                 0.00000E+00 
               
               
                 6 
                 0.00000E+00 
                  0.00000E+00 
                 0.00000E+00 
                 0.00000E+00 
                 0.00000E+00 
               
               
                 7 
                 1.48329E−02 
                 −9.20347E−04 
                 0.00000E+00 
                 0.00000E+00 
                 0.00000E+00 
               
               
                 8 
                 3.16264E−03 
                  4.17741E−03 
                 0.00000E+00 
                 0.00000E+00 
                 0.00000E+00 
               
               
                 12 
                 −7.44565E−04  
                 −1.42901E−03 
                 0.00000E+00 
                 0.00000E+00 
                 0.00000E+00 
               
               
                 13 
                 1.80337E−01 
                 −4.80759E−02 
                 4.57265E−03 
                 0.00000E+00 
                 0.00000E+00 
               
               
                 14 
                 1.50208E−02 
                 −4.69107E−03 
                 5.90742E−04 
                 0.00000E+00 
                 0.00000E+00 
               
               
                   
               
            
           
         
       
     
     In Table 4-1 and Table 4-2 above, in a case where a lens surface is a convex surface protruding toward the object side or a concave surface recessed toward the object side, its radius of curvature is set to a positive value; in a case where a lens surface is a convex surface protruding toward the image side or a concave surface recessed toward the image side, its radius of curvature is set to a negative value. 
     In addition, Table 4-1 and Table 4-2 above show the aspheric coefficients A4, A6, A8, A10, A12, A14 and A16 of each of the aspheric surfaces, which satisfy expression 1 above. 
     Here, as described above, the maximum HFOV co of the wide-angle lens  1000  as a whole is 115 degrees, that is, the following condition 2-1 is satisfied: 
       98°&lt;ω&lt;120°  (2-1)
 
     In condition 2-1, the maximum HFOV co is set to be greater than 98°, thereby expanding the maximum HFOV ω; the maximum HFOV co is set to be less than 120°, thereby avoiding a situation that a peripheral portion of an image becomes dark due to a light quantity ratio at the periphery of the wide-angle lens  1000  being smaller than a light quantity ratio at the center of the wide-angle lens  1000 . Further, the wide-angle lens  1000  is able to be miniaturized as a whole while the maximum HFOV co of the wide-angle lens  1000  is expanded. 
     In addition, in the wide-angle lens  1000  as a whole, the effective focal length f is 1.023 mm and the entrance pupil diameter HEP is 0.526 mm. Therefore, the following condition 2-2 is satisfied: 
         f/HEP&lt; 2.3  (2-2)
 
     In condition 2-2, the ratio of the effective focal length f to the entrance pupil diameter HEP of the wide-angle lens  1000  as a whole is set as f/HEP&lt;2.3, thereby ensuring the brightness of the wide-angle lens  1000 , and enabling use of the wide-angle lens  1000  in a high pixel imaging element. 
     In addition, as is clear from Table 3, the effective radius sd12 of the image side lens surface (that is, the second surface  2 ) of the first lens  110  is 3.013 mm, and the radius of curvature R12 of the second surface  2  of the first lens  110  is 3.310 mm. Therefore, the following condition 2-3 is satisfied: 
       0.890&lt; sd 12/ R 12&lt;0.970  (2-3)
 
     In condition 2-3, the ratio of the effective radius sd12 to the radius of curvature R12 of the second surface  2  of the first lens  110  is set to be greater than 0.890, thereby expanding the HFOV, in particular, to 98° or greater; the ratio of the effective radius sd12 to the radius of curvature R12 of the second surface  2  of the first lens  110  is set to be less than 0.970, thereby preventing the angle defined between the peripheral part of the second surface  2  of the first lens  110  made of glass and the tangent line from being excessively small, and further making it possible to perform a polishing process on the second surface  2  of the first lens  110 . 
     In addition, as is clear from Table 3, the radius of curvature R11 of the object side lens surface (that is, the first surface  1 ) of the first lens  110  is 11.363 mm, and the radius of curvature R12 of the image side lens surface (that is, the second surface  2 ) of the first lens  110  is 3.310 mm. Therefore, the following condition 2-4 is satisfied: 
       1.300&lt;( R 11+ R 12)/( R 11− R 12)&lt;1.900  (2-4)
 
     Moreover, the following condition 2-5 is satisfied: 
       1.600&lt;( R 11+ R 12)/( R 11− R 12)&lt;1.850  (2-5)
 
     In condition 2-4, (R11+R12)/(R11−R12) is set to be greater than 1.300, thereby preventing the radius of curvature R12 of the image side lens surface (that is, the second surface  2 ) of the first lens  110  from being excessively small, thus facilitating the molding of the second surface  2  of the first lens  110 . In another respect, the radius of curvature R11 of the object side lens surface (that is, the first surface  1 ) of the first lens  110  is able to be prevented from being excessively large, thereby avoiding an excessively large diameter of the first lens  110 , thus miniaturizing the wide-angle lens  1000 . In addition, (R11+R12)/(R11−R12) is set to be less than 1.900, thereby ensuring sufficient refractive power of the first lens  110 , thus facilitating the expansion of the maximum HFOV co of the first lens  110 . Moreover, a sufficient thickness of the first lens  110  is able to be ensured, so as to prevent the first lens  110  from being damaged due to impact or the like. 
     In condition 2-5, (R11+R12)/(R11−R12) is further set to be greater than 1.600, thereby further preventing the radius of curvature R12 of the image side lens surface (that is, the second surface  2 ) of the first lens  110  from being excessively small, thus further facilitating the molding of the second surface  2  of the first lens  110 . In another respect, the radius of curvature R11 of the object side lens surface (that is, the first surface  1 ) of the first lens  110  is able to be further prevented from being excessively large, thereby further avoiding an excessively large diameter of the first lens  110 , thus further miniaturizing the wide-angle lens  1000 . In addition, (R11+R12)/(R11−R12) is further set to be less than 1.850, thereby further ensuring sufficient refractive power of the first lens  110 , thus further facilitating the expansion of the maximum HFOV co of the first lens  110 . Moreover, a sufficient thickness of the first lens  110  is able to be further ensured, so as to further prevent the first lens  110  from being damaged due to impact or the like. 
     In addition, as is clear from Table 3, the thickness T1 of the first lens  110  is 1.561 mm (the thickness T1 of the first lens  110  is defined as a distance between the object side lens surface (that is, the first surface  1 ) of the first lens  110  and the image side lens surface (that is, the second surface  2 ) of the first lens  110  in the optical axis direction), the sag Sag12 of the image side lens surface (that is, the second surface  2 ) of the first lens  110  is 1.940 mm. Therefore, the following condition 2-6 is satisfied: 
       0.700&lt; T 1/ Sag 12&lt;1.100  (2-6)
 
     In condition 2-6, the ratio of the thickness T1 of the first lens  110  to the sag Sag12 of the image side lens surface (that is, the second surface  2 ) of the first lens  110  is set to be greater than 0.700, thereby ensuring a sufficient thickness of the first lens  110  to prevent the first lens  110  from being damaged due to impact or the like; the ratio of the thickness T1 of the first lens  110  to the sag Sag12 of the image side lens surface (that is, the second surface  2 ) of the first lens  110  is set to be less than 1.100, thereby avoiding an excessively large thickness of the first lens  110 , thus making it possible to achieve desired negative refractive power. 
     In addition, in the wide-angle lens  1000  of this embodiment, the object-to-image distance d of the wide-angle lens  1000  is 13.610 mm, and the effective focal length f of the wide-angle lens  1000  as a whole is 1.062 mm. Therefore, the following condition 2-7 is satisfied: 
       11.000&lt; d/f&lt; 15.000  (2-7)
 
     In condition 2-7, the ratio of the object-to-image distance d of the wide-angle lens  1000  to the effective focal length f of the wide-angle lens  1000  as a whole is set to be greater than 11.000, thereby enabling appropriate correction to be easily made for various aberrations, thus making it easy to achieve good optical characteristics; the ratio of the object-to-image distance d of the wide-angle lens  1000  to the effective focal length f of the wide-angle lens  1000  as a whole is set to be less than 15.000, thereby preventing the wide-angle lens  1000  from becoming excessively large while avoiding an excessively large overall length of the wide-angle lens  1000 . 
     In summary, in this embodiment, by configuring the wide-angle lens  1000  as above, as shown in  FIG. 6A  to  FIG. 8L , appropriate correction is enabled for various aberrations such as curvature of field, chromatic aberration of magnification, and coma. Moreover, the miniaturization is able to be achieved while the maximum HFOV co is expanded. 
       FIG. 9  illustrates a wide-angle lens according to Embodiment 3 of the disclosure.  FIG. 10A  illustrates curvature of field and distortion of the wide-angle lens according to Embodiment 3 of the disclosure.  FIG. 10B  illustrates curvature of field and distortion of the wide-angle lens according to Embodiment 3 of the disclosure.  FIG. 11A  illustrates lateral chromatic aberration (transverse chromatic aberration) of the wide-angle lens according to Embodiment 3 of the disclosure.  FIG. 11B  illustrates spherical aberration (longitudinal aberration) of the wide-angle lens according to Embodiment 3 of the disclosure.  FIG. 12A  to  FIG. 12L  illustrate transverse aberration of the wide-angle lens according to Embodiment 3 of the disclosure. Here, in  FIG. 10A ,  FIG. 10B ,  FIG. 11A ,  FIG. 11B , and  FIG. 12A  to  FIG. 12L , a correlation curve of red light R (having a wavelength of 656 nm) is denoted by R, a correlation curve of green light G (having a wavelength of 588 nm) is denoted by G, and a correlation curve of blue light B (having a wavelength of 486 nm) is denoted by B. T indicates being related to the meridian plane, and S indicates being related to the sagittal plane. Moreover, in  FIG. 12A  to  FIG. 12L , the maximum scale of the longitudinal axis is ±50.000 μm. 
     As shown in  FIG. 9 , the wide-angle lens  1000  includes, sequentially arranged from the object side (L 1  side), the first lens  110  (that is, the first lens  110  is located closest to the object side), the second lens  120  (that is, the second lens  120  is located on the image side of and adjacent to the first lens  110 ), the third lens  130 , the fourth lens  140 , the diaphragm  180 , the fifth lens  150 , the sixth lens  160  and the seventh lens  170 . Among them, the sixth lens  160  and the seventh lens  170  are bonded together by an adhesive to constitute a cemented lens. 
     Here, the wide-angle lens  1000  in this embodiment has the same basic structure (that is, whether each of the first lens  110 , the second lens  120 , the third lens  130 , the fourth lens  140 , the fifth lens  150 , the sixth lens  160  and the seventh lens  170  has positive refractive power or negative refractive power, whether each of these lenses is a glass lens or plastic lens, whether the object side surface and the image side surface of each of these lenses are convex surfaces or concave surfaces, and whether the object side surface and the image side surface are spherical surfaces or aspheric surfaces) as that of the wide-angle lens of Embodiment 1, and thus the details thereof will be omitted. 
     As shown in  FIG. 9 , similarly to Embodiment 1, the light-shielding sheet  190  is provided between the second lens  120  and the third lens  130 , the filter  200  is arranged on the image side of the seventh lens  170 , and the imaging element  300  is arranged on the image side of the filter  200 . 
     In this embodiment, in the lens system as a whole, the effective focal length f is 1.026 mm, the object-to-image distance (total track) d is 13.403 mm, the F value (image space F/#) is 2.02, the maximum HFOV (maximum half field angle) is 109 degrees, and the entrance pupil diameter HEP is 0.508 mm. 
     Table 5 shows physical properties of each surface of the wide-angle lens  1000  of this embodiment. Table 6-1 and Table 6-2 show aspheric coefficients of each surface of the wide-angle lens  1000  of this embodiment. 
     
       
         
           
               
               
               
               
               
               
               
               
             
               
                 TABLE 5 
               
               
                   
               
               
                   
                 Radius of 
                   
                   
                   
                 Effective 
                 Effective 
                   
               
               
                 Surface 
                 curvature 
                 Thickness 
                 N d   
                 v d   
                 focal length 
                 radius 
                 Sag 
               
               
                   
               
             
            
               
                   
               
            
           
           
               
               
               
               
               
               
               
               
            
               
                  1 
                 11.171 
                 1.300 
                 1.871 
                 40.73 
                 −1.467 
                 5.722 
                 1.578 
               
               
                  2 
                 3.204 
                 1.815 
                   
                   
                   
                 2.863 
                 1.766 
               
               
                  3* 
                 35.057 
                 0.600 
                 1.544 
                 56.4 
                   
                 2.675 
                 0.053 
               
               
                  4* 
                 1.388 
                 1.422 
                   
                   
                   
                 1.498 
                 1.147 
               
               
                  5* 
                 −5.882 
                 0.763 
                 1.544 
                 56.4 
                 3.456 
                 1.463 
                 −0.052 
               
               
                  6* 
                 −2.425 
                 0.839 
                   
                   
                   
                 1.348 
                 −0.220 
               
               
                  7* 
                 −6.368 
                 0.718 
                 1.635 
                 23.9 
                   
                 1.032 
                 −0.026 
               
               
                  8* 
                 −2.397 
                 −0.037 
                   
                   
                   
                 0.903 
                 −0.150 
               
               
                  9 
                 Infinite 
                 0.347 
               
               
                 (diaphragm) 
               
               
                 10 
                 7.103 
                 1.300 
                 1.697 
                 55.46 
                   
                 1.400 
                 0.139 
               
               
                 11 
                 −2.839 
                 0.135 
                   
                   
                   
                 1.400 
                 −0.369 
               
               
                 12* 
                 −4.077 
                 0.500 
                 1.635 
                 23.9 
                 11.542 
                 1.173 
                 −0.184 
               
               
                 13* 
                 1.068 
                 2.213 
                 1.544 
                 56.4 
                   
                 1.411 
                 1.091 
               
               
                 14* 
                 −2.294 
                 0.963 
                   
                   
                   
                 1.597 
                 −0.422 
               
               
                 15 
                 Infinite 
                 0.400 
               
               
                 16 
                 Infinite 
                 0.125 
               
               
                   
               
            
           
         
       
     
     In Table 5 above, the radius of curvature, thickness, effective focal length, effective radius, and sag are in units of mm. N d  represents a refractive index for a ray of 587.56 nm. V d  represents the Abbe number. * represents an aspheric surface. 
     
       
         
           
               
               
               
               
               
             
               
                 TABLE 6-1 
               
               
                   
               
               
                 Surface 
                 c (1/radius of curvature) 
                 K 
                 A4 
                 A6 
               
               
                   
               
             
            
               
                   
               
            
           
           
               
               
               
               
               
            
               
                 3 
                  2.85248E−02 
                 0.00000E+00 
                 −7.73953E−04  
                 −2.76248E−05 
               
               
                 4 
                  7.20578E−01 
                 −1.00000E+00  
                 1.69157E−02 
                  2.83585E−02 
               
               
                 5 
                 −1.69997E−01 
                 0.00000E+00 
                 4.77013E−03 
                  1.28269E−02 
               
               
                 6 
                 −4.12314E−01 
                 0.00000E+00 
                 4.38590E−02 
                  3.36563E−03 
               
               
                 7 
                 −1.57044E−01 
                 0.00000E+00 
                 5.20793E−02 
                 −9.74604E−03 
               
               
                 8 
                 −4.17218E−01 
                 0.00000E+00 
                 3.75209E−02 
                 −1.18387E−03 
               
               
                 12 
                 −2.45256E−01 
                 0.00000E+00 
                 1.12258E−02 
                 −2.18878E−02 
               
               
                 13 
                  9.36158E−01 
                 −1.00000E+00  
                 1.84892E−01 
                 −2.17248E−01 
               
               
                 14 
                 −4.35910E−01 
                 0.00000E+00 
                 6.08264E−02 
                 −6.37284E−02 
               
               
                   
               
            
           
         
       
     
     
       
         
           
               
               
               
               
               
               
             
               
                 TABLE 6-2 
               
               
                   
               
               
                 Surface 
                 A8 
                 A10 
                 A12 
                 A14 
                 A16 
               
               
                   
               
             
            
               
                   
               
            
           
           
               
               
               
               
               
               
            
               
                 3 
                 0.00000E+00 
                 0.00000E+00 
                 0.00000E+00 
                 0.00000E+00 
                 0.00000E+00 
               
               
                 4 
                 −1.08170E−02  
                 3.74135E−03 
                 0.00000E+00 
                 0.00000E+00 
                 0.00000E+00 
               
               
                 5 
                 −6.95368E−04  
                 2.73435E−05 
                 0.00000E+00 
                 0.00000E+00 
                 0.00000E+00 
               
               
                 6 
                 2.29705E−03 
                 −1.23857E−05  
                 0.00000E+00 
                 0.00000E+00 
                 0.00000E+00 
               
               
                 7 
                 8.85677E−03 
                 −7.73714E−05  
                 0.00000E+00 
                 0.00000E+00 
                 0.00000E+00 
               
               
                 8 
                 4.43504E−03 
                 9.66329E−04 
                 0.00000E+00 
                 0.00000E+00 
                 0.00000E+00 
               
               
                 12 
                 3.37862E−04 
                 9.82658E−03 
                 −3.53648E−03  
                 −1.65685E−04  
                 0.00000E+00 
               
               
                 13 
                 1.49413E−01 
                 −7.49877E−02  
                 2.96657E−02 
                 −5.71297E−03  
                 0.00000E+00 
               
               
                 14 
                 5.78846E−02 
                 −2.66940E−02  
                 6.28648E−03 
                 −5.86821E−04  
                 0.00000E+00 
               
               
                   
               
            
           
         
       
     
     In Table 6-1 and Table 6-2 above, in a case where a lens surface is a convex surface protruding toward the object side or a concave surface recessed toward the object side, its radius of curvature is set to a positive value; in a case where a lens surface is a convex surface protruding toward the image side or a concave surface recessed toward the image side, its radius of curvature is set to a negative value. 
     In addition, Table 6-1 and Table 6-2 above show the aspheric coefficients A4, A6, A8, A10, A12, A14 and A16 of each of the aspheric surfaces, which satisfy expression 1 above. 
     Here, as described above, the maximum HFOV co of the wide-angle lens  1000  as a whole is 109 degrees, that is, the following condition 3-1 is satisfied: 
       98°&lt;ω&lt;120°  (3-1)
 
     In condition 3-1, the maximum HFOV co is set to be greater than 98°, thereby expanding the maximum HFOV ω; the maximum HFOV co is set to be less than 120°, thereby avoiding a situation that a peripheral portion of an image becomes dark due to a light quantity ratio at the periphery of the wide-angle lens  1000  being smaller than a light quantity ratio at the center of the wide-angle lens  1000 . Further, the wide-angle lens  1000  is able to be miniaturized as a whole while the maximum HFOV ω of the wide-angle lens  1000  is expanded. 
     In addition, in the wide-angle lens  1000  as a whole, the effective focal length f is 1.026 mm and the entrance pupil diameter HEP is 0.508 mm. Therefore, the following condition 3-2 is satisfied: 
         f/HEP&lt; 2.3  (3-2)
 
     In condition 3-2, the ratio of the effective focal length f to the entrance pupil diameter HEP of the wide-angle lens  1000  as a whole is set as f/HEP&lt;2.3, thereby ensuring the brightness of the wide-angle lens  1000 , and enabling use of the wide-angle lens  1000  in a high pixel imaging element. 
     In addition, as is clear from Table 5, the effective radius sd12 of the image side lens surface (that is, the second surface  2 ) of the first lens  110  is 2.863 mm, and the radius of curvature R12 of the second surface  2  of the first lens  110  is 3.204 mm. Therefore, the following condition 3-3 is satisfied: 
       0.890&lt; sd 12/ R 12&lt;0.970  (3-3)
 
     In condition 3-3, the ratio of the effective radius sd12 to the radius of curvature R12 of the second surface  2  of the first lens  110  is set to be greater than 0.890, thereby expanding the HFOV, in particular, to 98° or greater; the ratio of the effective radius sd12 to the radius of curvature R12 of the second surface  2  of the first lens  110  is set to be less than 0.970, thereby preventing the angle defined between the peripheral part of the second surface  2  of the first lens  110  made of glass and the tangent line from being excessively small, and further making it possible to perform a polishing process on the second surface  2  of the first lens  110 . 
     In addition, as is clear from Table 5, the radius of curvature R11 of the object side lens surface (that is, the first surface  1 ) of the first lens  110  is 11.171 mm, and the radius of curvature R12 of the image side lens surface (that is, the second surface  2 ) of the first lens  110  is 3.204 mm. Therefore, the following condition 3-4 is satisfied: 
       1.300&lt;( R 11+ R 12)/( R 11− R 12)&lt;1.900  (3-4)
 
     Moreover, the following condition 3-5 is satisfied: 
       1.600&lt;( R 11+ R 12)/( R 11− R 12)&lt;1.850  (3-5)
 
     In condition 3-4, (R11+R12)/(R11−R12) is set to be greater than 1.300, thereby preventing the radius of curvature R12 of the image side lens surface (that is, the second surface  2 ) of the first lens  110  from being excessively small, thus facilitating the molding of the second surface  2  of the first lens  110 . In another respect, the radius of curvature R11 of the object side lens surface (that is, the first surface  1 ) of the first lens  110  is able to be prevented from being excessively large, thereby avoiding an excessively large diameter of the first lens  110 , thus miniaturizing the wide-angle lens  1000 . In addition, (R11+R12)/(R11−R12) is set to be less than 1.900, thereby ensuring sufficient refractive power of the first lens  110 , thus facilitating the expansion of the maximum HFOV co of the first lens  110 . Moreover, a sufficient thickness of the first lens  110  is able to be ensured, so as to prevent the first lens  110  from being damaged due to impact or the like. 
     In condition 3-5, (R11+R12)/(R11−R12) is further set to be greater than 1.600, thereby further preventing the radius of curvature R12 of the image side lens surface (that is, the second surface  2 ) of the first lens  110  from being excessively small, thus further facilitating the molding of the second surface  2  of the first lens  110 . In another respect, the radius of curvature R11 of the object side lens surface (that is, the first surface  1 ) of the first lens  110  is able to be further prevented from being excessively large, thereby further avoiding an excessively large diameter of the first lens  110 , thus further miniaturizing the wide-angle lens  1000 . In addition, (R11+R12)/(R11−R12) is further set to be less than 1.850, thereby further ensuring sufficient refractive power of the first lens  110 , thus further facilitating the expansion of the maximum HFOV co of the first lens  110 . Moreover, a sufficient thickness of the first lens  110  is able to be further ensured, so as to further prevent the first lens  110  from being damaged due to impact or the like. 
     In addition, as is clear from Table 5, the thickness T1 of the first lens  110  is 1.300 mm (the thickness T1 of the first lens  110  is defined as a distance between the object side lens surface (that is, the first surface  1 ) of the first lens  110  and the image side lens surface (that is, the second surface  2 ) of the first lens  110  in the optical axis direction), the sag Sag12 of the image side lens surface (that is, the second surface  2 ) of the first lens  110  is 1.766 mm. Therefore, the following condition 3-6 is satisfied: 
       0.700&lt; T 1/ Sag 12&lt;1.100  (3-6)
 
     In condition 3-6, the ratio of the thickness T1 of the first lens  110  to the sag Sag12 of the image side lens surface (that is, the second surface  2 ) of the first lens  110  is set to be greater than 0.700, thereby ensuring a sufficient thickness of the first lens  110  to prevent the first lens  110  from being damaged due to impact or the like; the ratio of the thickness T1 of the first lens  110  to the sag Sag12 of the image side lens surface (that is, the second surface  2 ) of the first lens  110  is set to be less than 1.100, thereby avoiding an excessively large thickness of the first lens  110 , thus making it possible to achieve desired negative refractive power. 
     In addition, in the wide-angle lens  1000  of this embodiment, the object-to-image distance d of the wide-angle lens  1000  is 13.403 mm, and the effective focal length f of the wide-angle lens  1000  as a whole is 1.026 mm. Therefore, the following condition 3-7 is satisfied: 
       11.000&lt; d/f&lt; 15.000  (3-7)
 
     In condition 3-7, the ratio of the object-to-image distance d of the wide-angle lens  1000  to the effective focal length f of the wide-angle lens  1000  as a whole is set to be greater than 11.000, thereby enabling appropriate correction to be easily made for various aberrations, thus making it easy to achieve good optical characteristics; the ratio of the object-to-image distance d of the wide-angle lens  1000  to the effective focal length f of the wide-angle lens  1000  as a whole is set to be less than 15.000, thereby preventing the wide-angle lens  1000  from becoming excessively large while avoiding an excessively large overall length of the wide-angle lens  1000 . 
     In summary, in this embodiment, by configuring the wide-angle lens  1000  as above, as shown in  FIG. 10A  to  FIG. 12L , appropriate correction is enabled for various aberrations such as curvature of field, chromatic aberration of magnification, and coma. Moreover, the miniaturization is able to be achieved while the maximum HFOV co is expanded. 
       FIG. 13  illustrates a wide-angle lens according to Embodiment 4 of the disclosure.  FIG. 14A  illustrates curvature of field and distortion of the wide-angle lens according to Embodiment 4 of the disclosure.  FIG. 14B  illustrates curvature of field and distortion of the wide-angle lens according to Embodiment 4 of the disclosure.  FIG. 15A  illustrates lateral chromatic aberration (transverse chromatic aberration) of the wide-angle lens according to Embodiment 4 of the disclosure.  FIG. 15B  illustrates spherical aberration (longitudinal aberration) of the wide-angle lens according to Embodiment 4 of the disclosure.  FIG. 16A  to  FIG. 16L  illustrate transverse aberration of the wide-angle lens according to Embodiment 4 of the disclosure. Here, in  FIG. 14A ,  FIG. 14B ,  FIG. 15A ,  FIG. 15B , and  FIG. 16A  to  FIG. 16L , a correlation curve of red light R (having a wavelength of 656 nm) is denoted by R, a correlation curve of green light G (having a wavelength of 588 nm) is denoted by G, and a correlation curve of blue light B (having a wavelength of 486 nm) is denoted by B. T indicates being related to the meridian plane, and S indicates being related to the sagittal plane. Moreover, in  FIG. 16A  to  FIG. 16L , the maximum scale of the longitudinal axis is ±50.000 μm. 
     As shown in  FIG. 13 , the wide-angle lens  1000  includes, sequentially arranged from the object side (L 1  side), the first lens  110  (that is, the first lens  110  is located closest to the object side), the second lens  120  (that is, the second lens  120  is located on the image side of and adjacent to the first lens  110 ), the third lens  130 , the fourth lens  140 , the diaphragm  180 , the fifth lens  150 , the sixth lens  160  and the seventh lens  170 . Among them, the sixth lens  160  and the seventh lens  170  are bonded together by an adhesive to constitute a cemented lens. 
     Here, the wide-angle lens  1000  in this embodiment has the same basic structure (that is, whether each of the first lens  110 , the second lens  120 , the third lens  130 , the fourth lens  140 , the fifth lens  150 , the sixth lens  160  and the seventh lens  170  has positive refractive power or negative refractive power, whether each of these lenses is a glass lens or plastic lens, whether the object side surface and the image side surface of each of these lenses are convex surfaces or concave surfaces, and whether the object side surface and the image side surface are spherical surfaces or aspheric surfaces) as that of the wide-angle lens of Embodiment 1, and thus the details thereof will be omitted. 
     As shown in  FIG. 13 , similarly to Embodiment 1, the light-shielding sheet  190  is provided between the second lens  120  and the third lens  130 , the filter  200  is arranged on the image side of the seventh lens  170 , and the imaging element  300  is arranged on the image side of the filter  200 . 
     In this embodiment, in the lens system as a whole, the effective focal length f is 1.011 mm, the object-to-image distance (total track) d is 13.404 mm, the F value (image space F/#) is 2.03, the maximum HFOV (maximum half field angle) is 109 degrees, and the entrance pupil diameter HEP is 0.498 mm. 
     Table 7 shows physical properties of each surface of the wide-angle lens  1000  of this embodiment. Table 8-1 and Table 8-2 show aspheric coefficients of each surface of the wide-angle lens  1000  of this embodiment. 
     
       
         
           
               
               
               
               
               
               
               
               
             
               
                 TABLE 7 
               
               
                   
               
               
                   
                 Radius of 
                   
                   
                   
                 Effective 
                 Effective 
                   
               
               
                 Surface 
                 curvature 
                 Thickness 
                 N d   
                 v d   
                 focal length 
                 radius 
                 Sag 
               
               
                   
               
             
            
               
                   
               
            
           
           
               
               
               
               
               
               
               
               
            
               
                  1 
                 11.850 
                 1.800 
                 1.871 
                 40.73 
                 −1.347 
                 6.043 
                 1.658 
               
               
                  2 
                 2.910 
                 1.717 
                   
                   
                   
                 2.623 
                 1.649 
               
               
                  3* 
                 23.043 
                 0.600 
                 1.544 
                 56.4 
                   
                 2.444 
                 0.033 
               
               
                  4* 
                 1.291 
                 1.276 
                   
                   
                   
                 1.435 
                 1.058 
               
               
                  5* 
                 −13.541 
                 0.750 
                 1.544 
                 56.4 
                 3.614 
                 1.355 
                 −0.010 
               
               
                  6* 
                 −3.273 
                 0.679 
                   
                   
                   
                 1.286 
                 −0.155 
               
               
                  7* 
                 −20.063 
                 0.710 
                 1.635 
                 23.9 
                   
                 1.034 
                 0.029 
               
               
                  8* 
                 −3.188 
                 0.056 
                   
                   
                   
                 0.886 
                 −0.100 
               
               
                  9 
                 Infinite 
                 0.076 
               
               
                 (diaphragm) 
               
               
                 10 
                 7.740 
                 1.320 
                 1.697 
                 55.46 
                   
                 1.500 
                 0.147 
               
               
                 11 
                 −2.450 
                 0.271 
                   
                   
                   
                 1.500 
                 −0.513 
               
               
                 12* 
                 −4.136 
                 0.500 
                 1.635 
                 23.9 
                 8.497 
                 1.083 
                 −0.170 
               
               
                 13* 
                 0.946 
                 2.180 
                 1.544 
                 56.4 
                   
                 1.342 
                 0.954 
               
               
                 14* 
                 −2.056 
                 0.944 
                   
                   
                   
                 1.566 
                 −0.443 
               
               
                 15 
                 Infinite 
                 0.400 
               
               
                 16 
                 Infinite 
                 0.125 
               
               
                   
               
            
           
         
       
     
     In Table 7 above, the radius of curvature, thickness, effective focal length, effective radius, and sag are in units of mm. N d  represents a refractive index for a ray of 587.56 nm. V d  represents the Abbe number. * represents an aspheric surface. 
     
       
         
           
               
               
               
               
               
             
               
                 TABLE 8-1 
               
               
                   
               
               
                 Surface 
                 c (1/radius of curvature) 
                 K 
                 A4 
                 A6 
               
               
                   
               
             
            
               
                   
               
            
           
           
               
               
               
               
               
            
               
                 3 
                  4.33971E−02 
                 0.00000E+00 
                 −6.82448E−03  
                  3.73911E−03 
               
               
                 4 
                  7.74346E−01 
                 −5.39587E+00  
                 2.32631E−01 
                 −1.17492E−01 
               
               
                 5 
                 −7.38477E−02 
                 0.00000E+00 
                 2.29113E−02 
                  4.37979E−03 
               
               
                 6 
                 −3.05528E−01 
                 0.00000E+00 
                 4.74057E−02 
                 −5.28192E−03 
               
               
                 7 
                 −4.98442E−02 
                 0.00000E+00 
                 4.27102E−02 
                 −4.22032E−04 
               
               
                 8 
                 −3.13660E−01 
                 0.00000E+00 
                 3.38907E−02 
                  3.26534E−03 
               
               
                 12 
                 −2.41789E−01 
                 0.00000E+00 
                 −3.09436E−02  
                  3.41185E−02 
               
               
                 13 
                  1.05668E+00 
                 −1.00000E+00  
                 5.66189E−04 
                 −1.14232E−02 
               
               
                 14 
                 −4.86390E−01 
                 0.00000E+00 
                 7.16605E−02 
                 −6.17165E−02 
               
               
                   
               
            
           
         
       
     
     
       
         
           
               
               
               
               
               
               
             
               
                 TABLE 8-2 
               
               
                   
               
               
                 Surface 
                 A8 
                 A10 
                 A12 
                 A14 
                 A16 
               
               
                   
               
             
            
               
                   
               
            
           
           
               
               
               
               
               
               
            
               
                 3 
                 −1.15147E−03  
                  1.50789E−04 
                 −7.30801E−06  
                 0.00000E+00 
                 0.00000E+00 
               
               
                 4 
                 7.01048E−02 
                 −7.98133E−03 
                 −4.17335E−03  
                 0.00000E+00 
                 0.00000E+00 
               
               
                 5 
                 1.21716E−02 
                 −8.91664E−03 
                 0.00000E+00 
                 0.00000E+00 
                 0.00000E+00 
               
               
                 6 
                 2.05279E−02 
                 −2.11693E−02 
                 5.41203E−03 
                 0.00000E+00 
                 0.00000E+00 
               
               
                 7 
                 6.15517E−03 
                  0.00000E+00 
                 0.00000E+00 
                 0.00000E+00 
                 0.00000E+00 
               
               
                 8 
                 8.49340E−03 
                  3.83965E−03 
                 −2.61241E−03  
                 0.00000E+00 
                 0.00000E+00 
               
               
                 12 
                 −5.25642E−02  
                  5.03801E−02 
                 −2.60337E−02  
                 5.67639E−03 
                 0.00000E+00 
               
               
                 13 
                 1.93193E−02 
                 −2.02628E−02 
                 1.27147E−02 
                 −3.03203E−03  
                 0.00000E+00 
               
               
                 14 
                 5.37377E−02 
                 −2.41958E−02 
                 5.72598E−03 
                 −5.29799E−04  
                 0.00000E+00 
               
               
                   
               
            
           
         
       
     
     In Table 8-1 and Table 8-2 above, in a case where a lens surface is a convex surface protruding toward the object side or a concave surface recessed toward the object side, its radius of curvature is set to a positive value; in a case where a lens surface is a convex surface protruding toward the image side or a concave surface recessed toward the image side, its radius of curvature is set to a negative value. 
     In addition, Table 8-1 and Table 8-2 above show the aspheric coefficients A4, A6, A8, A10, A12, A14 and A16 of each of the aspheric surfaces, which satisfy expression 1 above. 
     Here, as described above, the maximum HFOV co of the wide-angle lens  1000  as a whole is 109 degrees, that is, the following condition 4-1 is satisfied: 
       98°&lt;ω&lt;120°  (4-1)
 
     In condition 4-1, the maximum HFOV co is set to be greater than 98°, thereby expanding the maximum HFOV ω; the maximum HFOV co is set to be less than 120°, thereby avoiding a situation that a peripheral portion of an image becomes dark due to a light quantity ratio at the periphery of the wide-angle lens  1000  being smaller than a light quantity ratio at the center of the wide-angle lens  1000 . Further, the wide-angle lens  1000  is able to be miniaturized as a whole while the maximum HFOV co of the wide-angle lens  1000  is expanded. 
     In addition, in the wide-angle lens  1000  as a whole, the effective focal length f is 1.011 mm and the entrance pupil diameter HEP is 0.498 mm. Therefore, the following condition 4-2 is satisfied: 
         f/HEP&lt; 2.3  (4-2)
 
     In condition 4-2, the ratio of the effective focal length f to the entrance pupil diameter HEP of the wide-angle lens  1000  as a whole is set as f/HEP&lt;2.3, thereby ensuring the brightness of the wide-angle lens  1000 , and enabling use of the wide-angle lens  1000  in a high pixel imaging element. 
     In addition, as is clear from Table 7, the effective radius sd12 of the image side lens surface (that is, the second surface  2 ) of the first lens  110  is 2.623 mm, and the radius of curvature R12 of the second surface  2  of the first lens  110  is 2.910 mm. Therefore, the following condition 4-3 is satisfied: 
       0.890&lt; sd 12/ R 12&lt;0.970  (4-3)
 
     In condition 4-3, the ratio of the effective radius sd12 to the radius of curvature R12 of the second surface  2  of the first lens  110  is set to be greater than 0.890, thereby expanding the HFOV, in particular, to 98° or greater; the ratio of the effective radius sd12 to the radius of curvature R12 of the second surface  2  of the first lens  110  is set to be less than 0.970, thereby preventing the angle defined between the peripheral part of the second surface  2  of the first lens  110  made of glass and the tangent line from being excessively small, and further making it possible to perform a polishing process on the second surface  2  of the first lens  110 . 
     In addition, as is clear from Table 7, the radius of curvature R11 of the object side lens surface (that is, the first surface  1 ) of the first lens  110  is 11.850 mm, and the radius of curvature R12 of the image side lens surface (that is, the second surface  2 ) of the first lens  110  is 2.910 mm. Therefore, the following condition 4-4 is satisfied: 
       1.300&lt;( R 11+ R 12)/( R 11− R 12)&lt;1.900  (4-4)
 
     Moreover, the following condition 4-5 is satisfied: 
       1.600&lt;( R 11+ R 12)/( R 11− R 12)&lt;1.850  (4-5)
 
     In condition 4-4, (R11+R12)/(R11−R12) is set to be greater than 1.300, thereby preventing the radius of curvature R12 of the image side lens surface (that is, the second surface  2 ) of the first lens  110  from being excessively small, thus facilitating the molding of the second surface  2  of the first lens  110 . In another respect, the radius of curvature R11 of the object side lens surface (that is, the first surface  1 ) of the first lens  110  is able to be prevented from being excessively large, thereby avoiding an excessively large diameter of the first lens  110 , thus miniaturizing the wide-angle lens  1000 . In addition, (R11+R12)/(R11−R12) is set to be less than 1.900, thereby ensuring sufficient refractive power of the first lens  110 , thus facilitating the expansion of the maximum HFOV co of the first lens  110 . Moreover, a sufficient thickness of the first lens  110  is able to be ensured, so as to prevent the first lens  110  from being damaged due to impact or the like. 
     In condition 4-5, (R11+R12)/(R11−R12) is further set to be greater than 1.600, thereby further preventing the radius of curvature R12 of the image side lens surface (that is, the second surface  2 ) of the first lens  110  from being excessively small, thus further facilitating the molding of the second surface  2  of the first lens  110 . In another respect, the radius of curvature R11 of the object side lens surface (that is, the first surface  1 ) of the first lens  110  is able to be further prevented from being excessively large, thereby further avoiding an excessively large diameter of the first lens  110 , thus further miniaturizing the wide-angle lens  1000 . In addition, (R11+R12)/(R11−R12) is further set to be less than 1.850, thereby further ensuring sufficient refractive power of the first lens  110 , thus further facilitating the expansion of the maximum HFOV co of the first lens  110 . Moreover, a sufficient thickness of the first lens  110  is able to be further ensured, so as to further prevent the first lens  110  from being damaged due to impact or the like. 
     In addition, as is clear from Table 7, the thickness T1 of the first lens  110  is 1.800 mm (the thickness T1 of the first lens  110  is defined as a distance between the object side lens surface (that is, the first surface  1 ) of the first lens  110  and the image side lens surface (that is, the second surface  2 ) of the first lens  110  in the optical axis direction), the sag Sag12 of the image side lens surface (that is, the second surface  2 ) of the first lens  110  is 1.649 mm. Therefore, the following condition 4-6 is satisfied: 
       0.700&lt; T 1/ Sag 12&lt;1.100  (4-6)
 
     In condition 4-6, the ratio of the thickness T1 of the first lens  110  to the sag Sag12 of the image side lens surface (that is, the second surface  2 ) of the first lens  110  is set to be greater than 0.700, thereby ensuring a sufficient thickness of the first lens  110  to prevent the first lens  110  from being damaged due to impact or the like; the ratio of the thickness T1 of the first lens  110  to the sag Sag12 of the image side lens surface (that is, the second surface  2 ) of the first lens  110  is set to be less than 1.100, thereby avoiding an excessively large thickness of the first lens  110 , thus making it possible to achieve desired negative refractive power. 
     In addition, in the wide-angle lens  1000  of this embodiment, the object-to-image distance d of the wide-angle lens  1000  is 13.404 mm, and the effective focal length f of the wide-angle lens  1000  as a whole is 1.011 mm. Therefore, the following condition 4-7 is satisfied: 
       11.000&lt; d/f&lt; 15.000  (4-7)
 
     In condition 4-7, the ratio of the object-to-image distance d of the wide-angle lens  1000  to the effective focal length f of the wide-angle lens  1000  as a whole is set to be greater than 11.000, thereby enabling appropriate correction to be easily made for various aberrations, thus making it easy to achieve good optical characteristics; the ratio of the object-to-image distance d of the wide-angle lens  1000  to the effective focal length f of the wide-angle lens  1000  as a whole is set to be less than 15.000, thereby preventing the wide-angle lens  1000  from becoming excessively large while avoiding an excessively large overall length of the wide-angle lens  1000 . 
     In summary, in this embodiment, by configuring the wide-angle lens  1000  as above, as shown in  FIG. 14A  to  FIG. 16L , appropriate correction is enabled for various aberrations such as curvature of field, chromatic aberration of magnification, and coma. Moreover, the miniaturization is able to be achieved while the maximum HFOV co is expanded. 
       FIG. 17  illustrates a wide-angle lens according to Embodiment 5 of the disclosure.  FIG. 18A  illustrates curvature of field and distortion of the wide-angle lens according to Embodiment 5 of the disclosure.  FIG. 18B  illustrates curvature of field and distortion of the wide-angle lens according to Embodiment 5 of the disclosure.  FIG. 19A  illustrates lateral chromatic aberration (transverse chromatic aberration) of the wide-angle lens according to Embodiment 5 of the disclosure.  FIG. 19B  illustrates spherical aberration (longitudinal aberration) of the wide-angle lens according to Embodiment 5 of the disclosure.  FIG. 20A  to  FIG. 20L  illustrate transverse aberration of the wide-angle lens according to Embodiment 5 of the disclosure. Here, in  FIG. 18A ,  FIG. 18B ,  FIG. 19A ,  FIG. 19B , and  FIG. 20A  to  FIG. 20L , a correlation curve of red light R (having a wavelength of 656 nm) is denoted by R, a correlation curve of green light G (having a wavelength of 588 nm) is denoted by G, and a correlation curve of blue light B (having a wavelength of 486 nm) is denoted by B. T indicates being related to the meridian plane, and S indicates being related to the sagittal plane. Moreover, in  FIG. 20A  to  FIG. 20L , the maximum scale of the longitudinal axis is ±50.000 μm. 
     As shown in  FIG. 17 , the wide-angle lens  1000  includes, sequentially arranged from the object side (L 1  side), the first lens  110  (that is, the first lens  110  is located closest to the object side), the second lens  120  (that is, the second lens  120  is located on the image side of and adjacent to the first lens  110 ), the third lens  130 , the fourth lens  140 , the diaphragm  180 , the fifth lens  150 , the sixth lens  160  and the seventh lens  170 . Among them, the sixth lens  160  and the seventh lens  170  are bonded together by an adhesive to constitute a cemented lens. 
     Here, the wide-angle lens  1000  in this embodiment has the same basic structure (that is, whether each of the first lens  110 , the second lens  120 , the third lens  130 , the fourth lens  140 , the fifth lens  150 , the sixth lens  160  and the seventh lens  170  has positive refractive power or negative refractive power, whether each of these lenses is a glass lens or plastic lens, whether the object side surface and the image side surface of each of these lenses are convex surfaces or concave surfaces, and whether the object side surface and the image side surface are spherical surfaces or aspheric surfaces) as that of the wide-angle lens of Embodiment 1, and thus the details thereof will be omitted. 
     As shown in  FIG. 17 , similarly to Embodiment 1, the light-shielding sheet  190  is provided between the second lens  120  and the third lens  130 , the filter  200  is arranged on the image side of the seventh lens  170 , and the imaging element  300  is arranged on the image side of the filter  200 . 
     In this embodiment, in the lens system as a whole, the effective focal length f is 1.021 mm, the object-to-image distance (total track) d is 13.398 mm, the F value (image space F/#) is 2, the maximum HFOV (maximum half field angle) is 108 degrees, and the entrance pupil diameter HEP is 0.511 mm. 
     Table 9 shows physical properties of each surface of the wide-angle lens  1000  of this embodiment. Table 10-1 and Table 10-2 show aspheric coefficients of each surface of the wide-angle lens  1000  of this embodiment. 
     
       
         
           
               
               
               
               
               
               
               
               
             
               
                 TABLE 9 
               
               
                   
               
               
                   
                 Radius of 
                   
                   
                   
                 Effective 
                 Effective 
                   
               
               
                 Surface 
                 curvature 
                 Thickness 
                 N d   
                 v d   
                 focal length 
                 radius 
                 Sag 
               
               
                   
               
             
            
               
                   
               
            
           
           
               
               
               
               
               
               
               
               
            
               
                  1 
                 11.850 
                 1.800 
                 1.871 
                 40.73 
                 −1.258 
                 6.600 
                 2.008 
               
               
                  2 
                 2.810 
                 1.790 
                   
                   
                   
                 2.623 
                 1.802 
               
               
                  3* 
                 21.109 
                 0.610 
                 1.544 
                 56.4 
                   
                 2.450 
                 0.024 
               
               
                  4* 
                 1.226 
                 1.511 
                   
                   
                   
                 1.460 
                 1.206 
               
               
                  5* 
                 −41.052 
                 0.645 
                 1.544 
                 56.4 
                 3.259 
                 1.450 
                 −0.041 
               
               
                  6* 
                 −3.608 
                 0.559 
                   
                   
                   
                 1.410 
                 −0.234 
               
               
                  7* 
                 35.384 
                 0.625 
                 1.635 
                 23.9 
                   
                 1.170 
                 0.082 
               
               
                  8* 
                 −3.636 
                 0.050 
                   
                   
                   
                 1.100 
                 −0.133 
               
               
                  9 
                 Infinite 
                 0.157 
               
               
                 (diaphragm) 
               
               
                 10 
                 6.330 
                 1.200 
                 1.697 
                 55.46 
                   
                 1.500 
                 0.180 
               
               
                 11 
                 −3.350 
                 0.180 
                   
                   
                   
                 1.500 
                 −0.355 
               
               
                 12* 
                 −5.730 
                 0.510 
                 1.635 
                 23.9 
                 9.670 
                 1.250 
                 −0.186 
               
               
                 13* 
                 0.910 
                 2.250 
                 1.544 
                 56.4 
                   
                 1.410 
                 1.136 
               
               
                 14* 
                 −2.306 
                 0.986 
                   
                   
                   
                 1.820 
                 −0.375 
               
               
                 15 
                 Infinite 
                 0.400 
               
               
                 16 
                 Infinite 
                 0.125 
               
               
                   
               
            
           
         
       
     
     In Table 9 above, the radius of curvature, thickness, effective focal length, effective radius, and sag are in units of mm. N d  represents a refractive index for a ray of 587.56 nm. V d  represents the Abbe number. * represents an aspheric surface. 
     
       
         
           
               
               
               
               
               
             
               
                 TABLE 10-1 
               
               
                   
               
               
                 Surface 
                 c (1/radius of curvature) 
                 K 
                 A4 
                 A6 
               
               
                   
               
             
            
               
                   
               
            
           
           
               
               
               
               
               
            
               
                 3 
                  4.73738E−02 
                 0.00000E+00 
                 −5.16461E−03  
                 2.97096E−03 
               
               
                 4 
                  8.15727E−01 
                 −3.85594E+00  
                 2.02517E−01 
                 −7.83664E−02  
               
               
                 5 
                 −2.43593E−02 
                 0.00000E+00 
                 7.18080E−04 
                 1.54312E−02 
               
               
                 6 
                 −2.77185E−01 
                 0.00000E+00 
                 1.27000E−02 
                 1.84355E−02 
               
               
                 7 
                  2.82614E−02 
                 0.00000E+00 
                 1.29430E−02 
                 2.83444E−02 
               
               
                 8 
                 −2.75058E−01 
                 0.00000E+00 
                 5.20665E−03 
                 2.87756E−02 
               
               
                 12 
                 −1.74511E−01 
                 0.00000E+00 
                 −2.22912E−02  
                 −2.24026E−04  
               
               
                 13 
                  1.09890E+00 
                 −1.00000E+00  
                 5.45916E−02 
                 −8.55229E−02  
               
               
                 14 
                 −4.33708E−01 
                 0.00000E+00 
                 5.56964E−02 
                 −4.87201E−02  
               
               
                   
               
            
           
         
       
     
     
       
         
           
               
               
               
               
               
               
             
               
                 TABLE 10-2 
               
               
                   
               
               
                 Surface 
                 A8 
                 A10 
                 A12 
                 A14 
                 A16 
               
               
                   
               
             
            
               
                   
               
            
           
           
               
               
               
               
               
               
            
               
                 3 
                 −1.12779E−03  
                  1.69605E−04 
                 −9.24708E−06  
                 0.00000E+00 
                 0.00000E+00 
               
               
                 4 
                 5.54759E−02 
                 −1.43828E−02 
                 −3.40212E−05  
                 0.00000E+00 
                 0.00000E+00 
               
               
                 5 
                 4.27755E−03 
                 −5.97392E−03 
                 0.00000E+00 
                 0.00000E+00 
                 0.00000E+00 
               
               
                 6 
                 1.27283E−03 
                 −1.01399E−02 
                 2.46941E−03 
                 0.00000E+00 
                 0.00000E+00 
               
               
                 7 
                 −2.19533E−02  
                  8.91100E−03 
                 0.00000E+00 
                 0.00000E+00 
                 0.00000E+00 
               
               
                 8 
                 −2.59952E−02  
                  1.31396E−02 
                 0.00000E+00 
                 0.00000E+00 
                 0.00000E+00 
               
               
                 12 
                 −5.53989E−03  
                  2.10400E−02 
                 −2.03506E−02  
                 6.17103E−03 
                 0.00000E+00 
               
               
                 13 
                 7.91865E−02 
                 −3.44941E−02 
                 3.84031E−03 
                 7.90842E−04 
                 0.00000E+00 
               
               
                 14 
                 4.18221E−02 
                 −1.79457E−02 
                 3.88481E−03 
                 −3.05248E−04  
                 0.00000E+00 
               
               
                   
               
            
           
         
       
     
     In Table 10-1 and Table 10-2 above, in a case where a lens surface is a convex surface protruding toward the object side or a concave surface recessed toward the object side, its radius of curvature is set to a positive value; in a case where a lens surface is a convex surface protruding toward the image side or a concave surface recessed toward the image side, its radius of curvature is set to a negative value. 
     In addition, Table 10-1 and Table 10-2 above show the aspheric coefficients A4, A6, A8, A10, A12, A14 and A16 of each of the aspheric surfaces, which satisfy expression 1 above. 
     Here, as described above, the maximum HFOV co of the wide-angle lens  1000  as a whole is 108 degrees, that is, the following condition 5-1 is satisfied: 
       98°&lt;ω&lt;120°  (5-1)
 
     In condition 5-1, the maximum HFOV co is set to be greater than 98°, thereby expanding the maximum HFOV ω; the maximum HFOV co is set to be less than 120°, thereby avoiding a situation that a peripheral portion of an image becomes dark due to a light quantity ratio at the periphery of the wide-angle lens  1000  being smaller than a light quantity ratio at the center of the wide-angle lens  1000 . Further, the wide-angle lens  1000  is able to be miniaturized as a whole while the maximum HFOV co of the wide-angle lens  1000  is expanded. 
     In addition, in the wide-angle lens  1000  as a whole, the effective focal length f is 1.021 mm and the entrance pupil diameter HEP is 0.511 mm. Therefore, the following condition 5-2 is satisfied: 
         f/HEP&lt; 2.3  (5-2)
 
     In condition 5-2, the ratio of the effective focal length f to the entrance pupil diameter HEP of the wide-angle lens  1000  as a whole is set as f/HEP&lt;2.3, thereby ensuring the brightness of the wide-angle lens  1000 , and enabling use of the wide-angle lens  1000  in a high pixel imaging element. 
     In addition, as is clear from Table 9, the effective radius sd12 of the image side lens surface (that is, the second surface  2 ) of the first lens  110  is 2.623 mm, and the radius of curvature R12 of the second surface  2  of the first lens  110  is 2.810 mm. Therefore, the following condition 5-3 is satisfied: 
       0.890&lt; sd 12/ R 12&lt;0.970  (5-3)
 
     In condition 5-3, the ratio of the effective radius sd12 to the radius of curvature R12 of the second surface  2  of the first lens  110  is set to be greater than 0.890, thereby expanding the HFOV, in particular, to 98° or greater; the ratio of the effective radius sd12 to the radius of curvature R12 of the second surface  2  of the first lens  110  is set to be less than 0.970, thereby preventing the angle defined between the peripheral part of the second surface  2  of the first lens  110  made of glass and the tangent line from being excessively small, and further making it possible to perform a polishing process on the second surface  2  of the first lens  110 . 
     In addition, as is clear from Table 9, the radius of curvature R11 of the object side lens surface (that is, the first surface  1 ) of the first lens  110  is 11.850 mm, and the radius of curvature R12 of the image side lens surface (that is, the second surface  2 ) of the first lens  110  is 2.810 mm. Therefore, the following condition 5-4 is satisfied: 
       1.300&lt;( R 11+ R 12)/( R 11− R 12)&lt;1.900  (5-4)
 
     Moreover, the following condition 5-5 is satisfied: 
       1.600&lt;( R 11+ R 12)/( R 11− R 12)&lt;1.850  (5-5)
 
     In condition 5-4, (R11+R12)/(R11−R12) is set to be greater than 1.300, thereby preventing the radius of curvature R12 of the image side lens surface (that is, the second surface  2 ) of the first lens  110  from being excessively small, thus facilitating the molding of the second surface  2  of the first lens  110 . In another respect, the radius of curvature R11 of the object side lens surface (that is, the first surface  1 ) of the first lens  110  is able to be prevented from being excessively large, thereby avoiding an excessively large diameter of the first lens  110 , thus miniaturizing the wide-angle lens  1000 . In addition, (R11+R12)/(R11−R12) is set to be less than 1.900, thereby ensuring sufficient refractive power of the first lens  110 , thus facilitating the expansion of the maximum HFOV co of the first lens  110 . Moreover, a sufficient thickness of the first lens  110  is able to be ensured, so as to prevent the first lens  110  from being damaged due to impact or the like. 
     In condition 5-5, (R11+R12)/(R11−R12) is further set to be greater than 1.600, thereby further preventing the radius of curvature R12 of the image side lens surface (that is, the second surface  2 ) of the first lens  110  from being excessively small, thus further facilitating the molding of the second surface  2  of the first lens  110 . In another respect, the radius of curvature R11 of the object side lens surface (that is, the first surface  1 ) of the first lens  110  is able to be further prevented from being excessively large, thereby further avoiding an excessively large diameter of the first lens  110 , thus further miniaturizing the wide-angle lens  1000 . In addition, (R11+R12)/(R11−R12) is further set to be less than 1.850, thereby further ensuring sufficient refractive power of the first lens  110 , thus further facilitating the expansion of the maximum HFOV co of the first lens  110 . Moreover, a sufficient thickness of the first lens  110  is able to be further ensured, so as to further prevent the first lens  110  from being damaged due to impact or the like. 
     In addition, as is clear from Table 9, the thickness T1 of the first lens  110  is 1.800 mm (the thickness T1 of the first lens  110  is defined as a distance between the object side lens surface (that is, the first surface  1 ) of the first lens  110  and the image side lens surface (that is, the second surface  2 ) of the first lens  110  in the optical axis direction), the sag Sag12 of the image side lens surface (that is, the second surface  2 ) of the first lens  110  is 1.802 mm. Therefore, the following condition 5-6 is satisfied: 
       0.700&lt; T 1/ Sag 12&lt;1.100  (5-6)
 
     In condition 5-6, the ratio of the thickness T1 of the first lens  110  to the sag Sag12 of the image side lens surface (that is, the second surface  2 ) of the first lens  110  is set to be greater than 0.700, thereby ensuring a sufficient thickness of the first lens  110  to prevent the first lens  110  from being damaged due to impact or the like; the ratio of the thickness T1 of the first lens  110  to the sag Sag12 of the image side lens surface (that is, the second surface  2 ) of the first lens  110  is set to be less than 1.100, thereby avoiding an excessively large thickness of the first lens  110 , thus making it possible to achieve desired negative refractive power. 
     In addition, in the wide-angle lens  1000  of this embodiment, the object-to-image distance d of the wide-angle lens  1000  is 13.398 mm, and the effective focal length f of the wide-angle lens  1000  as a whole is 1.021 mm. Therefore, the following condition 5-7 is satisfied: 
       11.000&lt; d/f&lt; 15.000  (5-7)
 
     In condition 5-7, the ratio of the object-to-image distance d of the wide-angle lens  1000  to the effective focal length f of the wide-angle lens  1000  as a whole is set to be greater than 11.000, thereby enabling appropriate correction to be easily made for various aberrations, thus making it easy to achieve good optical characteristics; the ratio of the object-to-image distance d of the wide-angle lens  1000  to the effective focal length f of the wide-angle lens  1000  as a whole is set to be less than 15.000, thereby preventing the wide-angle lens  1000  from becoming excessively large while avoiding an excessively large overall length of the wide-angle lens  1000 . 
     In summary, in this embodiment, by configuring the wide-angle lens  1000  as above, as shown in  FIG. 18A  to  FIG. 20L , appropriate correction is enabled for various aberrations such as curvature of field, chromatic aberration of magnification, and coma. Moreover, the miniaturization is able to be achieved while the maximum HFOV co is expanded. 
       FIG. 21  illustrates a wide-angle lens according to Embodiment 6 of the disclosure.  FIG. 22A  illustrates curvature of field and distortion of the wide-angle lens according to Embodiment 6 of the disclosure.  FIG. 22B  illustrates curvature of field and distortion of the wide-angle lens according to Embodiment 6 of the disclosure.  FIG. 23A  illustrates lateral chromatic aberration (transverse chromatic aberration) of the wide-angle lens according to Embodiment 6 of the disclosure.  FIG. 23B  illustrates spherical aberration (longitudinal aberration) of the wide-angle lens according to Embodiment 6 of the disclosure.  FIG. 24A  to  FIG. 24L  illustrate transverse aberration of the wide-angle lens according to Embodiment 6 of the disclosure. Here, in  FIG. 22A ,  FIG. 22B ,  FIG. 23A ,  FIG. 23B , and  FIG. 24A  to  FIG. 24L , a correlation curve of red light R (having a wavelength of 656 nm) is denoted by R, a correlation curve of green light G (having a wavelength of 588 nm) is denoted by G, and a correlation curve of blue light B (having a wavelength of 486 nm) is denoted by B. T indicates being related to the meridian plane, and S indicates being related to the sagittal plane. Moreover, in  FIG. 24A  to  FIG. 24L , the maximum scale of the longitudinal axis is ±50.000 μm. 
     As shown in  FIG. 21 , the wide-angle lens  1000  includes, sequentially arranged from the object side (L 1  side), the first lens  110  (that is, the first lens  110  is located closest to the object side), the second lens  120  (that is, the second lens  120  is located on the image side of and adjacent to the first lens  110 ), the third lens  130 , the fourth lens  140 , the diaphragm  180 , the fifth lens  150 , the sixth lens  160  and the seventh lens  170 . Among them, the sixth lens  160  and the seventh lens  170  are bonded together by an adhesive to constitute a cemented lens. 
     Here, the wide-angle lens  1000  in this embodiment has the same basic structure (that is, whether each of the first lens  110 , the second lens  120 , the third lens  130 , the fourth lens  140 , the fifth lens  150 , the sixth lens  160  and the seventh lens  170  has positive refractive power or negative refractive power, whether each of these lenses is a glass lens or plastic lens, whether the object side surface and the image side surface of each of these lenses are convex surfaces or concave surfaces, and whether the object side surface and the image side surface are spherical surfaces or aspheric surfaces) as that of the wide-angle lens of Embodiment 1, and thus the details thereof will be omitted. 
     As shown in  FIG. 21 , similarly to Embodiment 1, the light-shielding sheet  190  is provided between the second lens  120  and the third lens  130 , the filter  200  is arranged on the image side of the seventh lens  170 , and the imaging element  300  is arranged on the image side of the filter  200 . 
     In this embodiment, in the lens system as a whole, the effective focal length f is 1.018 mm, the object-to-image distance (total track) d is 13.383 mm, the F value (image space F/#) is 2, the maximum HFOV (maximum half field angle) is 108 degrees, and the entrance pupil diameter HEP is 0.509 mm. 
     Table 11 shows physical properties of each surface of the wide-angle lens  1000  of this embodiment. Table 12-1 and Table 12-2 show aspheric coefficients of each surface of the wide-angle lens  1000  of this embodiment. 
     
       
         
           
               
               
               
               
               
               
               
               
             
               
                 TABLE 11 
               
               
                   
               
               
                   
                 Radius of 
                   
                   
                   
                 Effective 
                 Effective 
                   
               
               
                 Surface 
                 curvature 
                 Thickness 
                 N d   
                 v d   
                 focal length 
                 radius 
                 Sag 
               
               
                   
               
             
            
               
                   
               
            
           
           
               
               
               
               
               
               
               
               
            
               
                  1 
                 12.500 
                 1.700 
                 1.871 
                 40.73 
                 −1.310 
                 6.660 
                 1.922 
               
               
                  2 
                 2.910 
                 1.880 
                 1.000 
                   
                   
                 2.691 
                 1.803 
               
               
                  3* 
                 9.149 
                 0.600 
                 1.544 
                 56.4 
                   
                 2.900 
                 0.244 
               
               
                  4* 
                 1.191 
                 1.354 
                 1.000 
                   
                   
                 1.350 
                 1.100 
               
               
                  5* 
                 −14.140 
                 0.750 
                 1.544 
                 56.4 
                 3.338 
                 1.350 
                 −0.120 
               
               
                  6* 
                 −3.818 
                 0.381 
                 1.000 
                   
                   
                 1.391 
                 −0.200 
               
               
                  7* 
                 −22.250 
                 0.722 
                 1.635 
                 23.9 
                   
                 1.229 
                 0.100 
               
               
                  8* 
                 −2.713 
                 0.050 
                 1.000 
                   
                   
                 1.235 
                 −0.150 
               
               
                  9 
                 Infinite 
                 0.130 
                 1.000 
               
               
                 (diaphragm) 
               
               
                 10 
                 7.740 
                 1.320 
                 1.697 
                 55.46 
                   
                 1.500 
                 0.147 
               
               
                 11 
                 −2.450 
                 0.199 
                 1.000 
                   
                   
                 1.500 
                 −0.513 
               
               
                 12* 
                 −3.600 
                 0.510 
                 1.635 
                 23.9 
                 10.463 
                 1.250 
                 −0.259 
               
               
                 13* 
                 0.963 
                 2.282 
                 1.544 
                 56.4 
                   
                 1.441 
                 1.123 
               
               
                 14* 
                 −2.141 
                 0.980 
                 1.000 
                   
                   
                 1.883 
                 −0.360 
               
               
                 15 
                 Infinite 
                 0.400 
               
               
                 16 
                 Infinite 
                 0.125 
               
               
                   
               
            
           
         
       
     
     In Table 11 above, the radius of curvature, thickness, effective focal length, effective radius, and sag are in units of mm. N d  represents a refractive index for a ray of 587.56 nm. V d  represents the Abbe number. * represents an aspheric surface. 
     
       
         
           
               
               
               
               
               
             
               
                 TABLE 12-1 
               
               
                   
               
               
                 Surface 
                 c (1/radius of curvature) 
                 K 
                 A4 
                 A6 
               
               
                   
               
             
            
               
                   
               
            
           
           
               
               
               
               
               
            
               
                 3 
                  1.09306E−01 
                 0.00000E+00 
                 −4.51092E−03  
                 2.92728E−03 
               
               
                 4 
                  8.39842E−01 
                 −3.71100E+00  
                 2.15910E−01 
                 −7.58275E−02  
               
               
                 5 
                 −7.07214E−02 
                 0.00000E+00 
                 −5.47555E−03  
                 1.09203E−02 
               
               
                 6 
                 −2.61938E−01 
                 0.00000E+00 
                 1.43606E−02 
                 2.26240E−02 
               
               
                 7 
                 −4.49438E−02 
                 0.00000E+00 
                 1.40010E−02 
                 4.01310E−02 
               
               
                 8 
                 −3.68664E−01 
                 0.00000E+00 
                 1.66786E−02 
                 2.21644E−02 
               
               
                 12 
                 −2.77778E−01 
                 0.00000E+00 
                 −2.23667E−02  
                 7.48072E−03 
               
               
                 13 
                  1.03842E+00 
                 −1.00000E+00  
                 4.72309E−02 
                 −6.05266E−02  
               
               
                 14 
                 −4.67071E−01 
                 0.00000E+00 
                 5.78738E−02 
                 −4.73130E−02  
               
               
                   
               
            
           
         
       
     
     
       
         
           
               
               
               
               
               
               
             
               
                 TABLE 12-2 
               
               
                   
               
               
                 Surface 
                 A8 
                 A10 
                 A12 
                 A14 
                 A16 
               
               
                   
               
             
            
               
                   
               
            
           
           
               
               
               
               
               
               
            
               
                 3 
                 −1.14938E−03 
                  1.63223E−04 
                 −7.82147E−06  
                 0.00000E+00 
                 0.00000E+00 
               
               
                 4 
                  5.61909E−02 
                 −1.28652E−02 
                 −3.10366E−04  
                 0.00000E+00 
                 0.00000E+00 
               
               
                 5 
                  2.71037E−03 
                 −6.63668E−03 
                 0.00000E+00 
                 0.00000E+00 
                 0.00000E+00 
               
               
                 6 
                 −3.16016E−03 
                 −9.85165E−03 
                 2.97746E−03 
                 0.00000E+00 
                 0.00000E+00 
               
               
                 7 
                 −1.96461E−02 
                  8.38631E−03 
                 0.00000E+00 
                 0.00000E+00 
                 0.00000E+00 
               
               
                 8 
                 −1.03312E−02 
                  1.03923E−02 
                 0.00000E+00 
                 0.00000E+00 
                 0.00000E+00 
               
               
                 12 
                 −8.59213E−03 
                  1.81642E−02 
                 −1.67818E−02  
                 5.17215E−03 
                 0.00000E+00 
               
               
                 13 
                  5.15225E−02 
                 −2.02257E−02 
                 1.88707E−03 
                 3.30690E−04 
                 0.00000E+00 
               
               
                 14 
                  4.12895E−02 
                 −1.76625E−02 
                 3.69776E−03 
                 −2.59955E−04  
                 0.00000E+00 
               
               
                   
               
            
           
         
       
     
     In Table 12-1 and Table 12-2 above, in a case where a lens surface is a convex surface protruding toward the object side or a concave surface recessed toward the object side, its radius of curvature is set to a positive value; in a case where a lens surface is a convex surface protruding toward the image side or a concave surface recessed toward the image side, its radius of curvature is set to a negative value. 
     In addition, Table 12-1 and Table 12-2 above show the aspheric coefficients A4, A6, A8, A10, A12, A14 and A16 of each of the aspheric surfaces, which satisfy expression 1 above. 
     Here, as described above, the maximum HFOV co of the wide-angle lens  1000  as a whole is 108 degrees, that is, the following condition 6-1 is satisfied: 
       98°&lt;ω&lt;120°  (6-1)
 
     In condition 6-1, the maximum HFOV co is set to be greater than 98°, thereby expanding the maximum HFOV ω; the maximum HFOV co is set to be less than 120°, thereby avoiding a situation that a peripheral portion of an image becomes dark due to a light quantity ratio at the periphery of the wide-angle lens  1000  being smaller than a light quantity ratio at the center of the wide-angle lens  1000 . Further, the wide-angle lens  1000  is able to be miniaturized as a whole while the maximum HFOV co of the wide-angle lens  1000  is expanded. 
     In addition, in the wide-angle lens  1000  as a whole, the effective focal length f is 1.018 mm and the entrance pupil diameter HEP is 0.509 mm. Therefore, the following condition 6-2 is satisfied: 
         f/HEP&lt; 2.3  (6-2)
 
     In condition 6-2, the ratio of the effective focal length f to the entrance pupil diameter HEP of the wide-angle lens  1000  as a whole is set as f/HEP&lt;2.3, thereby ensuring the brightness of the wide-angle lens  1000 , and enabling use of the wide-angle lens  1000  in a high pixel imaging element. 
     In addition, as is clear from Table 11, the effective radius sd12 of the image side lens surface (that is, the second surface  2 ) of the first lens  110  is 2.691 mm, and the radius of curvature R12 of the second surface  2  of the first lens  110  is 2.910 mm. Therefore, the following condition 6-3 is satisfied: 
       0.890&lt; sd 12/ R 12&lt;0.970  (6-3)
 
     In condition 6-3, the ratio of the effective radius sd12 to the radius of curvature R12 of the second surface  2  of the first lens  110  is set to be greater than 0.890, thereby expanding the HFOV, in particular, to 98° or greater; the ratio of the effective radius sd12 to the radius of curvature R12 of the second surface  2  of the first lens  110  is set to be less than 0.970, thereby preventing the angle defined between the peripheral part of the second surface  2  of the first lens  110  made of glass and the tangent line from being excessively small, and further making it possible to perform a polishing process on the second surface  2  of the first lens  110 . 
     In addition, as is clear from Table 11, the radius of curvature R11 of the object side lens surface (that is, the first surface  1 ) of the first lens  110  is 12.500 mm, and the radius of curvature R12 of the image side lens surface (that is, the second surface  2 ) of the first lens  110  is 2.910 mm. Therefore, the following condition 6-4 is satisfied: 
       1.300&lt;( R 11+ R 12)/( R 11− R 12)&lt;1.900  (6-4)
 
     Moreover, the following condition 6-5 is satisfied: 
       1.600&lt;( R 11+ R 12)/( R 11− R 12)&lt;1.850  (6-5)
 
     In condition 6-4, (R11+R12)/(R11−R12) is set to be greater than 1.300, thereby preventing the radius of curvature R12 of the image side lens surface (that is, the second surface  2 ) of the first lens  110  from being excessively small, thus facilitating the molding of the second surface  2  of the first lens  110 . In another respect, the radius of curvature R11 of the object side lens surface (that is, the first surface  1 ) of the first lens  110  is able to be prevented from being excessively large, thereby avoiding an excessively large diameter of the first lens  110 , thus miniaturizing the wide-angle lens  1000 . In addition, (R11+R12)/(R11−R12) is set to be less than 1.900, thereby ensuring sufficient refractive power of the first lens  110 , thus facilitating the expansion of the maximum HFOV co of the first lens  110 . Moreover, a sufficient thickness of the first lens  110  is able to be ensured, so as to prevent the first lens  110  from being damaged due to impact or the like. 
     In condition 6-5, (R11+R12)/(R11−R12) is further set to be greater than 1.600, thereby further preventing the radius of curvature R12 of the image side lens surface (that is, the second surface  2 ) of the first lens  110  from being excessively small, thus further facilitating the molding of the second surface  2  of the first lens  110 . In another respect, the radius of curvature R11 of the object side lens surface (that is, the first surface  1 ) of the first lens  110  is able to be further prevented from being excessively large, thereby further avoiding an excessively large diameter of the first lens  110 , thus further miniaturizing the wide-angle lens  1000 . In addition, (R11+R12)/(R11−R12) is further set to be less than 1.850, thereby further ensuring sufficient refractive power of the first lens  110 , thus further facilitating the expansion of the maximum HFOV co of the first lens  110 . Moreover, a sufficient thickness of the first lens  110  is able to be further ensured, so as to further prevent the first lens  110  from being damaged due to impact or the like. 
     In addition, as is clear from Table 11, the thickness T1 of the first lens  110  is 1.700 mm (the thickness T1 of the first lens  110  is defined as a distance between the object side lens surface (that is, the first surface  1 ) of the first lens  110  and the image side lens surface (that is, the second surface  2 ) of the first lens  110  in the optical axis direction), the sag Sag12 of the image side lens surface (that is, the second surface  2 ) of the first lens  110  is 1.803 mm. Therefore, the following condition 6-6 is satisfied: 
       0.700&lt; T 1/ Sag 12&lt;1.100  (6-6)
 
     In condition 6-6, the ratio of the thickness T1 of the first lens  110  to the sag Sag12 of the image side lens surface (that is, the second surface  2 ) of the first lens  110  is set to be greater than 0.700, thereby ensuring a sufficient thickness of the first lens  110  to prevent the first lens  110  from being damaged due to impact or the like; the ratio of the thickness T1 of the first lens  110  to the sag Sag12 of the image side lens surface (that is, the second surface  2 ) of the first lens  110  is set to be less than 1.100, thereby avoiding an excessively large thickness of the first lens  110 , thus making it possible to achieve desired negative refractive power. In addition, in the wide-angle lens  1000  of this embodiment, the object-to-image distance d of the wide-angle lens  1000  is 13.383 mm, and the effective focal length f of the wide-angle lens  1000  as a whole is 1.018 mm. Therefore, the following condition 6-7 is satisfied: 
       11.000&lt; d/f&lt; 15.000  (6-7)
 
     In condition 6-7, the ratio of the object-to-image distance d of the wide-angle lens  1000  to the effective focal length f of the wide-angle lens  1000  as a whole is set to be greater than 11.000, thereby enabling appropriate correction to be easily made for various aberrations, thus making it easy to achieve good optical characteristics; the ratio of the object-to-image distance d of the wide-angle lens  1000  to the effective focal length f of the wide-angle lens  1000  as a whole is set to be less than 15.000, thereby preventing the wide-angle lens  1000  from becoming excessively large while avoiding an excessively large overall length of the wide-angle lens  1000 . 
     In summary, in this embodiment, by configuring the wide-angle lens  1000  as above, as shown in  FIG. 22A  to  FIG. 24L , appropriate correction is enabled for various aberrations such as curvature of field, chromatic aberration of magnification, and coma. Moreover, the miniaturization is able to be achieved while the maximum HFOV co is expanded. 
       FIG. 25  illustrates a wide-angle lens according to Embodiment 7 of the disclosure.  FIG. 26A  illustrates curvature of field and distortion of the wide-angle lens according to Embodiment 7 of the disclosure.  FIG. 26B  illustrates curvature of field and distortion of the wide-angle lens according to Embodiment 7 of the disclosure.  FIG. 27A  illustrates lateral chromatic aberration (transverse chromatic aberration) of the wide-angle lens according to Embodiment 7 of the disclosure.  FIG. 27B  illustrates spherical aberration (longitudinal aberration) of the wide-angle lens according to Embodiment 7 of the disclosure.  FIG. 28A  to  FIG. 28L  illustrate transverse aberration of the wide-angle lens according to Embodiment 7 of the disclosure. Here, in  FIG. 26A ,  FIG. 26B ,  FIG. 27A ,  FIG. 27B , and  FIG. 28A  to  FIG. 28L , a correlation curve of red light R (having a wavelength of 656 nm) is denoted by R, a correlation curve of green light G (having a wavelength of 588 nm) is denoted by G, and a correlation curve of blue light B (having a wavelength of 486 nm) is denoted by B. T indicates being related to the meridian plane, and S indicates being related to the sagittal plane. Moreover, in  FIG. 28A  to  FIG. 28L , a maximum scale of the longitudinal axis is ±50.000 μm. 
     As shown in  FIG. 25 , the wide-angle lens  1000  includes, sequentially arranged from the object side (L 1  side), the first lens  110 , the second lens  120 , the third lens  130 , the fourth lens  140 , the diaphragm  180 , the fifth lens  150 , the sixth lens  160  and the seventh lens  170 . Among them, the sixth lens  160  and the seventh lens  170  are bonded together by an adhesive to constitute a cemented lens. 
     Here, the wide-angle lens  1000  in this embodiment has the same basic structure (that is, whether each of the first lens  110  (located closest to the object side), the second lens  120  (located on the image side of and adjacent to the first lens  110 ), the third lens  130 , the fourth lens  140 , the fifth lens  150 , the sixth lens  160  and the seventh lens  170  has positive refractive power or negative refractive power, whether each of these lenses is a glass lens or plastic lens, whether the object side surface and the image side surface of each of these lenses are convex surfaces or concave surfaces, and whether the object side surface and the image side surface are spherical surfaces or aspheric surfaces) as that of the wide-angle lens of Embodiment 1, and thus the details thereof will be omitted. 
     As shown in  FIG. 25 , similarly to Embodiment 1, the light-shielding sheet  190  is provided between the second lens  120  and the third lens  130 , the filter  200  is arranged on the image side of the seventh lens  170 , and the imaging element  300  is arranged on the image side of the filter  200 . 
     In this embodiment, in the lens system as a whole, the effective focal length f is 1.019 mm, the object-to-image distance (total track) d is 13.381 mm, the F value (image space F/#) is 2.0163, the maximum HFOV (maximum half field angle) is 108 degrees, and the entrance pupil diameter HEP is 0.505 mm. 
     Table 13 shows physical properties of each surface of the wide-angle lens  1000  of this embodiment. Table 14-1 and Table 14-2 show aspheric coefficients of each surface of the wide-angle lens  1000  of this embodiment. 
     
       
         
           
               
               
               
               
               
               
               
               
             
               
                 TABLE 13 
               
               
                   
               
               
                   
                 Radius of 
                   
                   
                   
                 Effective 
                 Effective 
                   
               
               
                 Surface 
                 curvature 
                 Thickness 
                 N d   
                 v d   
                 focal length 
                 radius 
                 Sag 
               
               
                   
               
             
            
               
                   
               
            
           
           
               
               
               
               
               
               
               
               
            
               
                  1 
                 12.500 
                 1.700 
                 1.871 
                 40.73 
                 −1.310 
                 6.660 
                 1.922 
               
               
                  2 
                 2.910 
                 1.880 
                   
                   
                   
                 2.800 
                 2.117 
               
               
                  3* 
                 9.138 
                 0.600 
                 1.544 
                 56.4 
                   
                 2.900 
                 0.268 
               
               
                  4* 
                 1.191 
                 1.354 
                   
                   
                   
                 1.350 
                 1.100 
               
               
                  5* 
                 −11.789 
                 0.750 
                 1.544 
                 56.4 
                 3.394 
                 1.350 
                 −0.141 
               
               
                  6* 
                 −3.818 
                 0.381 
                   
                   
                   
                 1.391 
                 −0.200 
               
               
                  7* 
                 −22.250 
                 0.710 
                 1.635 
                 23.9 
                   
                 1.229 
                 0.100 
               
               
                  8* 
                 −2.713 
                 0.050 
                   
                   
                   
                 1.235 
                 −0.150 
               
               
                  9 
                 Infinite 
                 0.116 
               
               
                 (diaphragm) 
               
               
                 10 
                 7.740 
                 1.320 
                 1.697 
                 55.46 
                   
                 1.500 
                 0.147 
               
               
                 11 
                 −2.450 
                 0.225 
                   
                   
                   
                 1.500 
                 −0.513 
               
               
                 12* 
                 −3.600 
                 0.510 
                 1.635 
                 23.9 
                 10.463 
                 1.250 
                 −0.259 
               
               
                 13* 
                 0.963 
                 2.282 
                 1.544 
                 56.4 
                   
                 1.441 
                 1.123 
               
               
                 14* 
                 −2.141 
                 0.978 
                   
                   
                   
                 1.883 
                 −0.363 
               
               
                 15 
                 Infinite 
                 0.400 
               
               
                 16 
                 Infinite 
                 0.125 
               
               
                   
               
            
           
         
       
     
     In Table 11 above, the radius of curvature, thickness, effective focal length, effective radius, and sag are in units of mm. N d  represents a refractive index for a ray of 587.56 nm. V d  represents the Abbe number. * represents an aspheric surface. 
     
       
         
           
               
               
               
               
               
             
               
                 TABLE 14-1 
               
               
                   
               
               
                 Surface 
                 c (1/radius of curvature) 
                 K 
                 A4 
                 A6 
               
               
                   
               
             
            
               
                   
               
            
           
           
               
               
               
               
               
            
               
                 3 
                  1.09439E−01 
                 0.00000E+00 
                 −4.39546E−03  
                 2.94241E−03 
               
               
                 4 
                  8.39842E−01 
                 −3.71100E+00  
                 2.15910E−01 
                 −7.58275E−02  
               
               
                 5 
                 −8.48248E−02 
                 0.00000E+00 
                 −5.99821E−03  
                 9.40179E−03 
               
               
                 6 
                 −2.61938E−01 
                 0.00000E+00 
                 1.43606E−02 
                 2.26240E−02 
               
               
                 7 
                 −4.49438E−02 
                 0.00000E+00 
                 1.40010E−02 
                 4.01310E−02 
               
               
                 8 
                 −3.68664E−01 
                 0.00000E+00 
                 1.66786E−02 
                 2.21644E−02 
               
               
                 12 
                 −2.77778E−01 
                 0.00000E+00 
                 −2.23667E−02  
                 7.48072E−03 
               
               
                 13 
                  1.03842E+00 
                 −1.00000E+00  
                 4.72309E−02 
                 −6.05266E−02  
               
               
                 14 
                 −4.67071E−01 
                 0.00000E+00 
                 5.76337E−02 
                 −4.72421E−02  
               
               
                   
               
            
           
         
       
     
     
       
         
           
               
               
               
               
               
               
             
               
                 TABLE 14-2 
               
               
                   
               
               
                 Surface 
                 A8 
                 A10 
                 A12 
                 A14 
                 A16 
               
               
                   
               
             
            
               
                   
               
            
           
           
               
               
               
               
               
               
            
               
                 3 
                 −1.15296E−03 
                  1.63212E−04 
                 −7.75247E−06  
                 0.00000E+00 
                 0.00000E+00 
               
               
                 4 
                  5.61909E−02 
                 −1.28652E−02 
                 −3.10366E−04  
                 0.00000E+00 
                 0.00000E+00 
               
               
                 5 
                  3.12004E−03 
                 −6.74245E−03 
                 0.00000E+00 
                 0.00000E+00 
                 0.00000E+00 
               
               
                 6 
                 −3.16016E−03 
                 −9.85165E−03 
                 2.97746E−03 
                 0.00000E+00 
                 0.00000E+00 
               
               
                 7 
                 −1.96461E−02 
                  8.38631E−03 
                 0.00000E+00 
                 0.00000E+00 
                 0.00000E+00 
               
               
                 8 
                 −1.03312E−02 
                  1.03923E−02 
                 0.00000E+00 
                 0.00000E+00 
                 0.00000E+00 
               
               
                 12 
                 −8.59213E−03 
                  1.81642E−02 
                 −1.67818E−02  
                 5.17215E−03 
                 0.00000E+00 
               
               
                 13 
                  5.15225E−02 
                 −2.02257E−02 
                 1.88707E−03 
                 3.30690E−04 
                 0.00000E+00 
               
               
                 14 
                  4.13120E−02 
                 −1.76585E−02 
                 3.69817E−03 
                 −2.61279E−04  
                 0.00000E+00 
               
               
                   
               
            
           
         
       
     
     In Table 14-1 and Table 14-2 above, in a case where a lens surface is a convex surface protruding toward the object side or a concave surface recessed toward the object side, its radius of curvature is set to a positive value; in a case where a lens surface is a convex surface protruding toward the image side or a concave surface recessed toward the image side, its radius of curvature is set to a negative value. 
     In addition, Table 14-1 and Table 14-2 above show the aspheric coefficients A4, A6, A8, A10, A12, A14 and A16 of each of the aspheric surfaces, which satisfy expression 1 above. 
     Here, as described above, the maximum HFOV co of the wide-angle lens  1000  as a whole is 108 degrees, that is, the following condition 7-1 is satisfied: 
       98°&lt;ω&lt;120°  (7-1)
 
     In condition 7-1, the maximum HFOV co is set to be greater than 98°, thereby expanding the maximum HFOV ω; the maximum HFOV co is set to be less than 120°, thereby avoiding a situation that a peripheral portion of an image becomes dark due to a light quantity ratio at the periphery of the wide-angle lens  1000  being smaller than a light quantity ratio at the center of the wide-angle lens  1000 . Further, the wide-angle lens  1000  is able to be miniaturized as a whole while the maximum HFOV co of the wide-angle lens  1000  is expanded. 
     In addition, in the wide-angle lens  1000  as a whole, the effective focal length f is 1.019 mm and the entrance pupil diameter HEP is 0.505 mm. Therefore, the following condition 7-2 is satisfied: 
         f/HEP&lt; 2.3  (7-2)
 
     In condition 7-2, the ratio of the effective focal length f to the entrance pupil diameter HEP of the wide-angle lens  1000  as a whole is set as f/HEP&lt;2.3, thereby ensuring the brightness of the wide-angle lens  1000 , and enabling use of the wide-angle lens  1000  in a high pixel imaging element. 
     In addition, as is clear from Table 13, the effective radius sd12 of the image side lens surface (that is, the second surface  2 ) of the first lens  110  is 2.800 mm, and the radius of curvature R12 of the second surface  2  of the first lens  110  is 2.910 mm. Therefore, the following condition 7-3 is satisfied: 
       0.890&lt; sd 12/ R 12&lt;0.970  (7-3)
 
     In condition 7-3, the ratio of the effective radius sd12 to the radius of curvature R12 of the second surface  2  of the first lens  110  is set to be greater than 0.890, thereby expanding the HFOV, in particular, to 98° or greater; the ratio of the effective radius sd12 to the radius of curvature R12 of the second surface  2  of the first lens  110  is set to be less than 0.970, thereby preventing the angle defined between the peripheral part of the second surface  2  of the first lens  110  made of glass and the tangent line from being excessively small, and further making it possible to perform a polishing process on the second surface  2  of the first lens  110 . 
     In addition, as is clear from Table 13, the radius of curvature R11 of the object side lens surface (that is, the first surface  1 ) of the first lens  110  is 12.500 mm, and the radius of curvature R12 of the image side lens surface (that is, the second surface  2 ) of the first lens  110  is 2.910 mm. Therefore, the following condition 7-4 is satisfied: 
       1.300&lt;( R 11+ R 12)/( R 11− R 12)&lt;1.900  (7-4)
 
     Moreover, the following condition 7-5 is satisfied: 
       1.600&lt;( R 11+ R 12)/( R 11− R 12)&lt;1.850  (7-5)
 
     In condition 7-4, (R11+R12)/(R11−R12) is set to be greater than 1.300, thereby preventing the radius of curvature R12 of the image side lens surface (that is, the second surface  2 ) of the first lens  110  from being excessively small, thus facilitating the molding of the second surface  2  of the first lens  110 . In another respect, the radius of curvature R11 of the object side lens surface (that is, the first surface  1 ) of the first lens  110  is able to be prevented from being excessively large, thereby avoiding an excessively large diameter of the first lens  110 , thus miniaturizing the wide-angle lens  1000 . In addition, (R11+R12)/(R11−R12) is set to be less than 1.900, thereby ensuring sufficient refractive power of the first lens  110 , thus facilitating the expansion of the maximum HFOV co of the first lens  110 . Moreover, a sufficient thickness of the first lens  110  is able to be ensured, so as to prevent the first lens  110  from being damaged due to impact or the like. 
     In condition 7-5, (R11+R12)/(R11−R12) is further set to be greater than 1.600, thereby further preventing the radius of curvature R12 of the image side lens surface (that is, the second surface  2 ) of the first lens  110  from being excessively small, thus further facilitating the molding of the second surface  2  of the first lens  110 . In another respect, the radius of curvature R11 of the object side lens surface (that is, the first surface  1 ) of the first lens  110  is able to be further prevented from being excessively large, thereby further avoiding an excessively large diameter of the first lens  110 , thus further miniaturizing the wide-angle lens  1000 . In addition, (R11+R12)/(R11−R12) is further set to be less than 1.850, thereby further ensuring sufficient refractive power of the first lens  110 , thus further facilitating the expansion of the maximum HFOV co of the first lens  110 . Moreover, a sufficient thickness of the first lens  110  is able to be further ensured, so as to further prevent the first lens  110  from being damaged due to impact or the like. 
     In addition, as is clear from Table 13, the thickness T1 of the first lens  110  is 1.700 mm (the thickness T1 of the first lens  110  is defined as a distance between the object side lens surface (that is, the first surface  1 ) of the first lens  110  and the image side lens surface (that is, the second surface  2 ) of the first lens  110  in the optical axis direction), the sag Sag12 of the image side lens surface (that is, the second surface  2 ) of the first lens  110  is 2.117 mm. Therefore, the following condition 7-6 is satisfied: 
       0.700&lt; T 1/ Sag 12&lt;1.100  (7-6)
 
     In condition 7-6, the ratio of the thickness T1 of the first lens  110  to the sag Sag12 of the image side lens surface (that is, the second surface  2 ) of the first lens  110  is set to be greater than 0.700, thereby ensuring a sufficient thickness of the first lens  110  to prevent the first lens  110  from being damaged due to impact or the like; the ratio of the thickness T1 of the first lens  110  to the sag Sag12 of the image side lens surface (that is, the second surface  2 ) of the first lens  110  is set to be less than 1.100, thereby avoiding an excessively large thickness of the first lens  110 , thus making it possible to achieve desired negative refractive power. 
     In addition, in the wide-angle lens  1000  of this embodiment, the object-to-image distance d of the wide-angle lens  1000  is 13.381 mm, and the effective focal length f of the wide-angle lens  1000  as a whole is 1.019 mm. Therefore, the following condition 7-7 is satisfied: 
       11.000&lt; d/f&lt; 15.000  (7-7)
 
     In condition 7-7, the ratio of the object-to-image distance d of the wide-angle lens  1000  to the effective focal length f of the wide-angle lens  1000  as a whole is set to be greater than 11.000, thereby enabling appropriate correction to be easily made for various aberrations, thus making it easy to achieve good optical characteristics; the ratio of the object-to-image distance d of the wide-angle lens  1000  to the effective focal length f of the wide-angle lens  1000  as a whole is set to be less than 15.000, thereby preventing the wide-angle lens  1000  from becoming excessively large while avoiding an excessively large overall length of the wide-angle lens  1000 . 
     In summary, in this embodiment, by configuring the wide-angle lens  1000  as above, as shown in  FIG. 26A  to  FIG. 28L , appropriate correction is enabled for various aberrations such as curvature of field, chromatic aberration of magnification, and coma. Moreover, the miniaturization is able to be achieved while the maximum HFOV co is expanded. 
       FIG. 29  illustrates a wide-angle lens according to Embodiment 8 of the disclosure.  FIG. 30A  illustrates curvature of field and distortion of the wide-angle lens according to Embodiment 8 of the disclosure.  FIG. 30B  illustrates curvature of field and distortion of the wide-angle lens according to Embodiment 8 of the disclosure.  FIG. 31A  illustrates lateral chromatic aberration (transverse chromatic aberration) of the wide-angle lens according to Embodiment 8 of the disclosure.  FIG. 31B  illustrates spherical aberration (longitudinal aberration) of the wide-angle lens according to Embodiment 8 of the disclosure.  FIG. 32A  to  FIG. 32L  illustrate transverse aberration of the wide-angle lens according to Embodiment 8 of the disclosure. Here, in  FIG. 30A ,  FIG. 30B ,  FIG. 31A ,  FIG. 31B , and  FIG. 32A  to  FIG. 32L , a correlation curve of red light R (having a wavelength of 656 nm) is denoted by R, a correlation curve of green light G (having a wavelength of 588 nm) is denoted by G, and a correlation curve of blue light B (having a wavelength of 486 nm) is denoted by B. T indicates being related to the meridian plane, and S indicates being related to the sagittal plane. Moreover, in  FIG. 32A  to  FIG. 32L , the maximum scale of the longitudinal axis is ±50.000 μm. 
     As shown in  FIG. 29 , the wide-angle lens  1000  includes, sequentially arranged from the object side (L 1  side), the first lens  110  (that is, the first lens  110  is located closest to the object side), the second lens  120  (that is, the second lens  120  is located on the image side of and adjacent to the first lens  110 ), the third lens  130 , the fourth lens  140 , the diaphragm  180 , the fifth lens  150 , the sixth lens  160  and the seventh lens  170 . Among them, the sixth lens  160  and the seventh lens  170  are bonded together by an adhesive to constitute a cemented lens. 
     Here, the wide-angle lens  1000  in this embodiment has the same basic structure (that is, whether each of the first lens  110 , the second lens  120 , the third lens  130 , the fourth lens  140 , the fifth lens  150 , the sixth lens  160  and the seventh lens  170  has positive refractive power or negative refractive power, whether each of these lenses is a glass lens or plastic lens, whether the object side surface and the image side surface of each of these lenses are convex surfaces or concave surfaces, and whether the object side surface and the image side surface are spherical surfaces or aspheric surfaces) as that of the wide-angle lens of Embodiment 1, and thus the details thereof will be omitted. 
     As shown in  FIG. 29 , similarly to Embodiment 1, the light-shielding sheet  190  is provided between the second lens  120  and the third lens  130 , the filter  200  is arranged on the image side of the seventh lens  170 , and the imaging element  300  is arranged on the image side of the filter  200 . 
     In this embodiment, in the lens system as a whole, the effective focal length f is 1.019 mm, the object-to-image distance (total track) d is 13.397 mm, the F value (image space F/#) is 2.012, the maximum HFOV (maximum half field angle) is 108.004 degrees, and the entrance pupil diameter HEP is 0.506 mm. 
     Table 15 shows physical properties of each surface of the wide-angle lens  1000  of this embodiment. Table 16-1 and Table 16-2 show aspheric coefficients of each surface of the wide-angle lens  1000  of this embodiment. 
     
       
         
           
               
               
               
               
               
               
               
               
             
               
                 TABLE 15 
               
               
                   
               
               
                   
                 Radius of 
                   
                   
                   
                 Effective 
                 Effective 
                   
               
               
                 Surface 
                 curvature 
                 Thickness 
                 N d   
                 v d   
                 focal length 
                 radius 
                 Sag 
               
               
                   
               
             
            
               
                   
               
            
           
           
               
               
               
               
               
               
               
               
            
               
                  1 
                 12.100 
                 1.730 
                 1.871 
                 40.73 
                 −1.415 
                 6.600 
                 1.959 
               
               
                  2 
                 2.910 
                 1.765 
                   
                   
                   
                 2.731 
                 1.905 
               
               
                  3* 
                 7.693 
                 0.600 
                 1.544 
                 56.4 
                   
                 2.900 
                 0.355 
               
               
                  4* 
                 1.237 
                 1.517 
                   
                   
                   
                 1.419 
                 1.095 
               
               
                  5* 
                 −6.607 
                 0.850 
                 1.544 
                 56.4 
                 4.381 
                 1.288 
                 −0.185 
               
               
                  6* 
                 −3.507 
                 0.202 
                   
                   
                   
                 1.325 
                 −0.154 
               
               
                  7* 
                 −12.641 
                 0.700 
                 1.635 
                 23.9 
                   
                 1.201 
                 0.040 
               
               
                  8* 
                 −3.228 
                 0.050 
                   
                   
                   
                 1.137 
                 −0.160 
               
               
                  9 
                 Infinite 
                 0.129 
               
               
                 (diaphragm) 
               
               
                 10 
                 5.000 
                 1.360 
                 1.697 
                 55.46 
                   
                 1.500 
                 0.230 
               
               
                 11 
                 −2.580 
                 0.260 
                   
                   
                   
                 1.500 
                 −0.481 
               
               
                 12* 
                 −3.864 
                 0.550 
                 1.635 
                 23.9 
                 10.147 
                 1.326 
                 −0.300 
               
               
                 13* 
                 0.980 
                 2.190 
                 1.544 
                 56.4 
                   
                 1.450 
                 1.074 
               
               
                 14* 
                 −2.151 
                 0.969 
                   
                   
                   
                 1.856 
                 −0.370 
               
               
                 15 
                 Infinite 
                 0.400 
               
               
                 16 
                 Infinite 
                 0.125 
               
               
                   
               
            
           
         
       
     
     In Table 15 above, the radius of curvature, thickness, effective focal length, effective radius, and sag are in units of mm. N d  represents a refractive index for a ray of 587.56 nm. V d  represents the Abbe number. * represents an aspheric surface. 
     
       
         
           
               
               
               
               
               
             
               
                 TABLE 16-1 
               
               
                   
               
               
                 Surface 
                 c (1/radius of curvature) 
                 K 
                 A4 
                 A6 
               
               
                   
               
             
            
               
                   
               
            
           
           
               
               
               
               
               
            
               
                 3 
                  1.29990E−01 
                 0.00000E+00 
                 1.79733E−03 
                 −1.14149E−03 
               
               
                 4 
                  8.08669E−01 
                 −4.00000E+00  
                 2.15100E−01 
                 −8.02378E−02 
               
               
                 5 
                 −1.51355E−01 
                 0.00000E+00 
                 −1.09624E−02  
                 −8.73052E−03 
               
               
                 6 
                 −2.85185E−01 
                 0.00000E+00 
                 4.64269E−03 
                  4.90763E−03 
               
               
                 7 
                 −7.91052E−02 
                 0.00000E+00 
                 1.02155E−02 
                  7.50888E−03 
               
               
                 8 
                 −3.09828E−01 
                 0.00000E+00 
                 7.49234E−03 
                  1.54584E−03 
               
               
                 12 
                 −2.58792E−01 
                 0.00000E+00 
                 −3.14257E−02  
                  2.35226E−03 
               
               
                 13 
                  1.02041E+00 
                 −1.00000E+00  
                 3.07479E−02 
                 −4.89661E−02 
               
               
                 14 
                 −4.64857E−01 
                 0.00000E+00 
                 4.79842E−02 
                 −2.97957E−02 
               
               
                   
               
            
           
         
       
     
     
       
         
           
               
               
               
               
               
               
             
               
                 TABLE 16-2 
               
               
                   
               
               
                 Surface 
                 A8 
                 A10 
                 A12 
                 A14 
                 A16 
               
               
                   
               
             
            
               
                   
               
            
           
           
               
               
               
               
               
               
            
               
                 3 
                 −6.11588E−05  
                  1.50045E−05 
                 3.90615E−08 
                 0.00000E+00 
                 0.00000E+00 
               
               
                 4 
                 4.96308E−02 
                 −1.37651E−02 
                 1.87863E−04 
                 0.00000E+00 
                 0.00000E+00 
               
               
                 5 
                 2.50539E−03 
                 −1.94316E−04 
                 −2.18386E−04  
                 0.00000E+00 
                 0.00000E+00 
               
               
                 6 
                 2.37631E−03 
                  4.68175E−04 
                 1.19525E−03 
                 0.00000E+00 
                 0.00000E+00 
               
               
                 7 
                 1.14133E−02 
                  6.53638E−04 
                 0.00000E+00 
                 0.00000E+00 
                 0.00000E+00 
               
               
                 8 
                 1.36753E−02 
                 −1.98505E−03 
                 0.00000E+00 
                 0.00000E+00 
                 0.00000E+00 
               
               
                 12 
                 3.38366E−03 
                 −2.00010E−03 
                 6.86525E−04 
                 0.00000E+00 
                 0.00000E+00 
               
               
                 13 
                 2.79270E−02 
                 −5.22149E−03 
                 −1.20343E−04  
                 0.00000E+00 
                 0.00000E+00 
               
               
                 14 
                 2.26165E−02 
                 −7.19858E−03 
                 9.87041E−04 
                 0.00000E+00 
                 0.00000E+00 
               
               
                   
               
            
           
         
       
     
     In Table 16-1 and Table 16-2 above, in a case where a lens surface is a convex surface protruding toward the object side or a concave surface recessed toward the object side, its radius of curvature is set to a positive value; in a case where a lens surface is a convex surface protruding toward the image side or a concave surface recessed toward the image side, its radius of curvature is set to a negative value. 
     In addition, Table 16-1 and Table 16-2 above show the aspheric coefficients A4, A6, A8, A10, A12, A14 and A16 of each of the aspheric surfaces, which satisfy expression 1 above. 
     Here, as described above, the maximum HFOV co of the wide-angle lens  1000  as a whole is 108.004 degrees, that is, the following condition 8-1 is satisfied: 
       98°&lt;ω&lt;120°  (8-1)
 
     In condition 8-1, the maximum HFOV co is set to be greater than 98°, thereby expanding the maximum HFOV ω; the maximum HFOV co is set to be less than 120°, thereby avoiding a situation that a peripheral portion of an image becomes dark due to a light quantity ratio at the periphery of the wide-angle lens  1000  being smaller than a light quantity ratio at the center of the wide-angle lens  1000 . Further, the wide-angle lens  1000  is able to be miniaturized as a whole while the maximum HFOV co of the wide-angle lens  1000  is expanded. 
     In addition, in the wide-angle lens  1000  as a whole, the effective focal length f is 1.019 mm and the entrance pupil diameter HEP is 0.506 mm. Therefore, the following condition 8-2 is satisfied: 
         f/HEP&lt; 2.3  (8-2)
 
     In condition 8-2, the ratio of the effective focal length f to the entrance pupil diameter HEP of the wide-angle lens  1000  as a whole is set as f/HEP&lt;2.3, thereby ensuring the brightness of the wide-angle lens  1000 , and enabling use of the wide-angle lens  1000  in a high pixel imaging element. 
     In addition, as is clear from Table 15, the effective radius sd12 of the image side lens surface (that is, the second surface  2 ) of the first lens  110  is 2.731 mm, and the radius of curvature R12 of the second surface  2  of the first lens  110  is 2.910 mm. Therefore, the following condition 8-3 is satisfied: 
       0.890&lt; sd 12/ R 12&lt;0.970  (8-3)
 
     In condition 8-3, the ratio of the effective radius sd12 to the radius of curvature R12 of the second surface  2  of the first lens  110  is set to be greater than 0.890, thereby expanding the HFOV, in particular, to 98° or greater; the ratio of the effective radius sd12 to the radius of curvature R12 of the second surface  2  of the first lens  110  is set to be less than 0.970, thereby preventing the angle defined between the peripheral part of the second surface  2  of the first lens  110  made of glass and the tangent line from being excessively small, and further making it possible to perform a polishing process on the second surface  2  of the first lens  110 . 
     In addition, as is clear from Table 15, the radius of curvature R11 of the object side lens surface (that is, the first surface  1 ) of the first lens  110  is 12.100 mm, and the radius of curvature R12 of the image side lens surface (that is, the second surface  2 ) of the first lens  110  is 2.910 mm. Therefore, the following condition 8-4 is satisfied: 
       1.300&lt;( R 11+ R 12)/( R 11− R 12)&lt;1.900  (8-4)
 
     Moreover, the following condition 8-5 is satisfied: 
       1.600&lt;( R 11+ R 12)/( R 11− R 12)&lt;1.850  (8-5)
 
     In condition 8-4, (R11+R12)/(R11−R12) is set to be greater than 1.300, thereby preventing the radius of curvature R12 of the image side lens surface (that is, the second surface  2 ) of the first lens  110  from being excessively small, thus facilitating the molding of the second surface  2  of the first lens  110 . In another respect, the radius of curvature R11 of the object side lens surface (that is, the first surface  1 ) of the first lens  110  is able to be prevented from being excessively large, thereby avoiding an excessively large diameter of the first lens  110 , thus miniaturizing the wide-angle lens  1000 . In addition, (R11+R12)/(R11−R12) is set to be less than 1.900, thereby ensuring sufficient refractive power of the first lens  110 , thus facilitating the expansion of the maximum HFOV co of the first lens  110 . Moreover, a sufficient thickness of the first lens  110  is able to be ensured, so as to prevent the first lens  110  from being damaged due to impact or the like. 
     In condition 8-5, (R11+R12)/(R11−R12) is further set to be greater than 1.600, thereby further preventing the radius of curvature R12 of the image side lens surface (that is, the second surface  2 ) of the first lens  110  from being excessively small, thus further facilitating the molding of the second surface  2  of the first lens  110 . In another respect, the radius of curvature R11 of the object side lens surface (that is, the first surface  1 ) of the first lens  110  is able to be further prevented from being excessively large, thereby further avoiding an excessively large diameter of the first lens  110 , thus further miniaturizing the wide-angle lens  1000 . In addition, (R11+R12)/(R11−R12) is further set to be less than 1.850, thereby further ensuring sufficient refractive power of the first lens  110 , thus further facilitating the expansion of the maximum HFOV co of the first lens  110 . Moreover, a sufficient thickness of the first lens  110  is able to be further ensured, so as to further prevent the first lens  110  from being damaged due to impact or the like. 
     In addition, as is clear from Table 15, the thickness T1 of the first lens  110  is 1.730 mm (the thickness T1 of the first lens  110  is defined as a distance between the object side lens surface (that is, the first surface  1 ) of the first lens  110  and the image side lens surface (that is, the second surface  2 ) of the first lens  110  in the optical axis direction), the sag Sag12 of the image side lens surface (that is, the second surface  2 ) of the first lens  110  is 1.905 mm. Therefore, the following condition 8-6 is satisfied: 
       0.700&lt; T 1/ Sag 12&lt;1.100  (8-6)
 
     In condition 8-6, the ratio of the thickness T1 of the first lens  110  to the sag Sag12 of the image side lens surface (that is, the second surface  2 ) of the first lens  110  is set to be greater than 0.700, thereby ensuring a sufficient thickness of the first lens  110  to prevent the first lens  110  from being damaged due to impact or the like; the ratio of the thickness T1 of the first lens  110  to the sag Sag12 of the image side lens surface (that is, the second surface  2 ) of the first lens  110  is set to be less than 1.100, thereby avoiding an excessively large thickness of the first lens  110 , thus making it possible to achieve desired negative refractive power. 
     In addition, in the wide-angle lens  1000  of this embodiment, the object-to-image distance d of the wide-angle lens  1000  is 13.397 mm, and the effective focal length f of the wide-angle lens  1000  as a whole is 1.019 mm. Therefore, the following condition 8-7 is satisfied: 
       11.000&lt; d/f&lt; 15.000  (8-7)
 
     In condition 8-7, the ratio of the object-to-image distance d of the wide-angle lens  1000  to the effective focal length f of the wide-angle lens  1000  as a whole is set to be greater than 11.000, thereby enabling appropriate correction to be easily made for various aberrations, thus making it easy to achieve good optical characteristics; the ratio of the object-to-image distance d of the wide-angle lens  1000  to the effective focal length f of the wide-angle lens  1000  as a whole is set to be less than 15.000, thereby preventing the wide-angle lens  1000  from becoming excessively large while avoiding an excessively large overall length of the wide-angle lens  1000 . 
     In summary, in this embodiment, by configuring the wide-angle lens  1000  as above, as shown in  FIG. 30A  to  FIG. 32L , appropriate correction is enabled for various aberrations such as curvature of field, chromatic aberration of magnification, and coma. Moreover, the miniaturization is able to be achieved while the maximum HFOV co is expanded. 
       FIG. 33  illustrates a wide-angle lens according to Embodiment 9 of the disclosure.  FIG. 34A  illustrates curvature of field and distortion of the wide-angle lens according to Embodiment 9 of the disclosure.  FIG. 34B  illustrates curvature of field and distortion of the wide-angle lens according to Embodiment 9 of the disclosure.  FIG. 35A  illustrates lateral chromatic aberration (transverse chromatic aberration) of the wide-angle lens according to Embodiment 9 of the disclosure.  FIG. 35B  illustrates spherical aberration (longitudinal aberration) of the wide-angle lens according to Embodiment 9 of the disclosure.  FIG. 36A  to  FIG. 36L  illustrate transverse aberration of the wide-angle lens according to Embodiment 9 of the disclosure. Here, in  FIG. 34A ,  FIG. 34B ,  FIG. 35A ,  FIG. 35B , and  FIG. 36A  to  FIG. 36L , a correlation curve of red light R (having a wavelength of 656 nm) is denoted by R, a correlation curve of green light G (having a wavelength of 588 nm) is denoted by G, and a correlation curve of blue light B (having a wavelength of 486 nm) is denoted by B. T indicates being related to the meridian plane, and S indicates being related to the sagittal plane. Moreover, in  FIG. 36A  to  FIG. 4L , a maximum scale of the longitudinal axis is ±50.000 μm. 
     As shown in  FIG. 33 , the wide-angle lens  1000  includes, sequentially arranged from the object side (L 1  side), the first lens  110  (that is, the first lens  110  is located closest to the object side), the second lens  120  (that is, the second lens  120  is located on the image side of and adjacent to the first lens  110 ), the third lens  130 , the fourth lens  140 , the diaphragm  180 , the fifth lens  150 , the sixth lens  160  and the seventh lens  170 . Among them, the sixth lens  160  and the seventh lens  170  are bonded together by an adhesive to constitute a cemented lens. 
     Here, the wide-angle lens  1000  in this embodiment has the same basic structure (that is, whether each of the first lens  110 , the second lens  120 , the third lens  130 , the fourth lens  140 , the fifth lens  150 , the sixth lens  160  and the seventh lens  170  has positive refractive power or negative refractive power, whether each of these lenses is a glass lens or plastic lens, whether the object side surface and the image side surface of each of these lenses are convex surfaces or concave surfaces, and whether the object side surface and the image side surface are spherical surfaces or aspheric surfaces) as that of the wide-angle lens of Embodiment 1, and thus the details thereof will be omitted. 
     As shown in  FIG. 33 , similarly to Embodiment 1, the light-shielding sheet  190  is provided between the second lens  120  and the third lens  130 , the filter  200  is arranged on the image side of the seventh lens  170 , and the imaging element  300  is arranged on the image side of the filter  200 . 
     In this embodiment, in the lens system as a whole, the effective focal length f is 1.030 mm, the object-to-image distance (total track) d is 13.609 mm, the F value (image space F/#) is 2, the maximum HFOV (maximum half field angle) is 106 degrees, and the entrance pupil diameter HEP is 0.515 mm. 
     Table 17 shows physical properties of each surface of the wide-angle lens  1000  of this embodiment. Table 18-1 and Table 18-2 show aspheric coefficients of each surface of the wide-angle lens  1000  of this embodiment. 
     
       
         
           
               
               
               
               
               
               
               
               
             
               
                 TABLE 17 
               
               
                   
               
               
                   
                 Radius of 
                   
                   
                   
                 Effective 
                 Effective 
                   
               
               
                 Surface 
                 curvature 
                 Thickness 
                 N d   
                 v d   
                 focal length 
                 radius 
                 Sag 
               
               
                   
               
             
            
               
                   
               
            
           
           
               
               
               
               
               
               
               
               
            
               
                  1 
                 12.641 
                 1.659 
                 1.804 
                 46.5 
                 −1.262 
                 6.461 
                 1.778 
               
               
                  2 
                 3.168 
                 1.968 
                   
                   
                   
                 2.907 
                 1.908 
               
               
                  3* 
                 −22.811 
                 0.600 
                 1.544 
                 56.4 
                   
                 2.671 
                 0.073 
               
               
                  4* 
                 1.268 
                 1.587 
                   
                   
                   
                 1.367 
                 1.223 
               
               
                  5* 
                 3.542 
                 1.200 
                 1.544 
                 56.4 
                 3.623 
                 1.366 
                 0.226 
               
               
                  6* 
                 8.543 
                 0.036 
                   
                   
                   
                 1.267 
                 −0.085 
               
               
                  7* 
                 4.456 
                 0.592 
                 1.639 
                 23.5 
                   
                 1.111 
                 0.209 
               
               
                  8* 
                 −9.668 
                 0.248 
                   
                   
                   
                 1.111 
                 0.147 
               
               
                  9 
                 Infinite 
                 0.078 
               
               
                 (diaphragm) 
               
               
                 10 
                 6.001 
                 1.129 
                 1.697 
                 55.46 
                   
                 1.400 
                 0.166 
               
               
                 11 
                 −2.824 
                 0.247 
                   
                   
                   
                 1.400 
                 −0.371 
               
               
                 12* 
                 −5.445 
                 0.500 
                 1.639 
                 23.5 
                 6.310 
                 1.124 
                 −0.130 
               
               
                 13* 
                 1.090 
                 2.170 
                 1.544 
                 56.4 
                   
                 1.407 
                 0.922 
               
               
                 14* 
                 −1.971 
                 1.070 
                   
                   
                   
                 1.634 
                 −0.537 
               
               
                 15 
                 Infinite 
                 0.400 
               
               
                 16 
                 Infinite 
                 0.125 
               
               
                   
               
            
           
         
       
     
     In Table 17 above, the radius of curvature, thickness, effective focal length, effective radius, and sag are in units of mm. N d  represents a refractive index for a ray of 587.56 nm. V d  represents the Abbe number. * represents an aspheric surface. 
     
       
         
           
               
               
               
               
               
             
               
                 TABLE 18-1 
               
               
                   
               
               
                 Surface 
                 c (1/radius of curvature) 
                 K 
                 A4 
                 A6 
               
               
                   
               
             
            
               
                   
               
            
           
           
               
               
               
               
               
            
               
                 3 
                 −4.38390E−02  
                 0.00000E+00 
                 1.02948E−02 
                 −1.01140E−03  
               
               
                 4 
                 7.88668E−01 
                 −1.13571E+00  
                 5.66499E−02 
                 1.84231E−03 
               
               
                 5 
                 2.82343E−01 
                 0.00000E+00 
                 −2.18543E−02  
                 5.16357E−03 
               
               
                 6 
                 1.17050E−01 
                 0.00000E+00 
                 −6.48711E−02  
                 −8.41810E−03  
               
               
                 7 
                 2.24418E−01 
                 0.00000E+00 
                 3.04785E−02 
                 1.99197E−02 
               
               
                 8 
                 −1.03429E−01  
                 0.00000E+00 
                 9.05286E−02 
                 3.48783E−02 
               
               
                 12 
                 −1.83670E−01  
                 0.00000E+00 
                 −3.32106E−02  
                 4.95833E−02 
               
               
                 13 
                 9.17180E−01 
                 −3.67711E+00  
                 1.58393E−01 
                 −3.03404E−02  
               
               
                 14 
                 −5.07238E−01  
                 −6.42125E−01  
                 3.25791E−02 
                 −8.99922E−03  
               
               
                   
               
            
           
         
       
     
     
       
         
           
               
               
               
               
               
               
             
               
                 TABLE 18-2 
               
               
                   
               
               
                 Surface 
                 A8 
                 A10 
                 A12 
                 A14 
                 A16 
               
               
                   
               
             
            
               
                   
               
            
           
           
               
               
               
               
               
               
            
               
                 3 
                 2.82136E−05 
                 8.57444E−16 
                 0.00000E+00 
                 0.00000E+00 
                 0.00000E+00 
               
               
                 4 
                 3.99185E−02 
                 −2.56858E−02  
                 9.68214E−03 
                 0.00000E+00 
                 0.00000E+00 
               
               
                 5 
                 −3.88312E−04  
                 0.00000E+00 
                 0.00000E+00 
                 0.00000E+00 
                 0.00000E+00 
               
               
                 6 
                 3.26148E−03 
                 0.00000E+00 
                 0.00000E+00 
                 0.00000E+00 
                 0.00000E+00 
               
               
                 7 
                 −6.50576E−03  
                 0.00000E+00 
                 0.00000E+00 
                 0.00000E+00 
                 0.00000E+00 
               
               
                 8 
                 4.33217E−03 
                 0.00000E+00 
                 0.00000E+00 
                 0.00000E+00 
                 0.00000E+00 
               
               
                 12 
                 −4.63097E−02  
                 2.53604E−02 
                 −5.68334E−03  
                 0.00000E+00 
                 0.00000E+00 
               
               
                 13 
                 −2.77646E−02  
                 2.45247E−02 
                 −5.43979E−03  
                 0.00000E+00 
                 0.00000E+00 
               
               
                 14 
                 4.06471E−03 
                 −7.04269E−04  
                 4.21913E−05 
                 0.00000E+00 
                 0.00000E+00 
               
               
                   
               
            
           
         
       
     
     In Table 18-1 and Table 18-2 above, in a case where a lens surface is a convex surface protruding toward the object side or a concave surface recessed toward the object side, its radius of curvature is set to a positive value; in a case where a lens surface is a convex surface protruding toward the image side or a concave surface recessed toward the image side, its radius of curvature is set to a negative value. 
     In addition, Table 18-1 and Table 18-2 above show the aspheric coefficients A4, A6, A8, A10, A12, A14 and A16 of each of the aspheric surfaces, which satisfy expression 1 above. 
     Here, as described above, the maximum HFOV co of the wide-angle lens  1000  as a whole is 106 degrees, that is, the following condition 9-1 is satisfied: 
       98°&lt;ω&lt;120°  (9-1)
 
     In condition 9-1, the maximum HFOV ω is set to be greater than 98°, thereby expanding the maximum HFOV ω; the maximum HFOV ω is set to be less than 120°, thereby avoiding a situation that a peripheral portion of an image becomes dark due to a light quantity ratio at the periphery of the wide-angle lens  1000  being smaller than a light quantity ratio at the center of the wide-angle lens  1000 . Further, the wide-angle lens  1000  is able to be miniaturized as a whole while the maximum HFOV co of the wide-angle lens  1000  is expanded. 
     In addition, in the wide-angle lens  1000  as a whole, the effective focal length f is 1.030 mm and the entrance pupil diameter HEP is 0.515 mm. Therefore, the following condition 9-2 is satisfied: 
         f/HEP&lt; 2.3  (9-2)
 
     In condition 9-2, the ratio of the effective focal length f to the entrance pupil diameter HEP of the wide-angle lens  1000  as a whole is set as f/HEP&lt;2.3, thereby ensuring the brightness of the wide-angle lens  1000 , and enabling use of the wide-angle lens  1000  in a high pixel imaging element. 
     In addition, as is clear from Table 17, the effective radius sd12 of the image side lens surface (that is, the second surface  2 ) of the first lens  110  is 2.907 mm, and the radius of curvature R12 of the second surface  2  of the first lens  110  is 3.168 mm. Therefore, the following condition 9-3 is satisfied: 
       0.890&lt; sd 12/ R 12&lt;0.970  (9-3)
 
     In condition 9-3, the ratio of the effective radius sd12 to the radius of curvature R12 of the second surface  2  of the first lens  110  is set to be greater than 0.890, thereby expanding the HFOV, in particular, to 98° or greater; the ratio of the effective radius sd12 to the radius of curvature R12 of the second surface  2  of the first lens  110  is set to be less than 0.970, thereby preventing the angle defined between the peripheral part of the second surface  2  of the first lens  110  made of glass and the tangent line from being excessively small, and further making it possible to perform a polishing process on the second surface  2  of the first lens  110 . 
     In addition, as is clear from Table 17, the radius of curvature R11 of the object side lens surface (that is, the first surface  1 ) of the first lens  110  is 12.641 mm, and the radius of curvature R12 of the image side lens surface (that is, the second surface  2 ) of the first lens  110  is 3.168 mm. Therefore, the following condition 9-4 is satisfied: 
       1.300&lt;( R 11+ R 12)/( R 11− R 12)&lt;1.900  (9-4)
 
     Moreover, the following condition 9-5 is satisfied: 
       1.600&lt;( R 11+ R 12)/( R 11− R 12)&lt;1.850  (9-5)
 
     In condition 9-4, (R11+R12)/(R11−R12) is set to be greater than 1.300, thereby preventing the radius of curvature R12 of the image side lens surface (that is, the second surface  2 ) of the first lens  110  from being excessively small, thus facilitating the molding of the second surface  2  of the first lens  110 . In another respect, the radius of curvature R11 of the object side lens surface (that is, the first surface  1 ) of the first lens  110  is able to be prevented from being excessively large, thereby avoiding an excessively large diameter of the first lens  110 , thus miniaturizing the wide-angle lens  1000 . In addition, (R11+R12)/(R11−R12) is set to be less than 1.900, thereby ensuring sufficient refractive power of the first lens  110 , thus facilitating the expansion of the maximum HFOV co of the first lens  110 . Moreover, a sufficient thickness of the first lens  110  is able to be ensured, so as to prevent the first lens  110  from being damaged due to impact or the like. 
     In condition 9-5, (R11+R12)/(R11−R12) is further set to be greater than 1.600, thereby further preventing the radius of curvature R12 of the image side lens surface (that is, the second surface  2 ) of the first lens  110  from being excessively small, thus further facilitating the molding of the second surface  2  of the first lens  110 . In another respect, the radius of curvature R11 of the object side lens surface (that is, the first surface  1 ) of the first lens  110  is able to be further prevented from being excessively large, thereby further avoiding an excessively large diameter of the first lens  110 , thus further miniaturizing the wide-angle lens  1000 . In addition, (R11+R12)/(R11−R12) is further set to be less than 1.850, thereby further ensuring sufficient refractive power of the first lens  110 , thus further facilitating the expansion of the maximum HFOV co of the first lens  110 . Moreover, a sufficient thickness of the first lens  110  is able to be further ensured, so as to further prevent the first lens  110  from being damaged due to impact or the like. 
     In addition, as is clear from Table 17, the thickness T1 of the first lens  110  is 1.659 mm (the thickness T1 of the first lens  110  is defined as a distance between the object side lens surface (that is, the first surface  1 ) of the first lens  110  and the image side lens surface (that is, the second surface  2 ) of the first lens  110  in the optical axis direction), the sag Sag12 of the image side lens surface (that is, the second surface  2 ) of the first lens  110  is 1.908 mm. Therefore, the following condition 9-6 is satisfied: 
       0.700&lt; T 1/ Sag 12&lt;1.100  (9-6)
 
     In condition 9-6, the ratio of the thickness T1 of the first lens  110  to the sag Sag12 of the image side lens surface (that is, the second surface  2 ) of the first lens  110  is set to be greater than 0.700, thereby ensuring a sufficient thickness of the first lens  110  to prevent the first lens  110  from being damaged due to impact or the like; the ratio of the thickness T1 of the first lens  110  to the sag Sag12 of the image side lens surface (that is, the second surface  2 ) of the first lens  110  is set to be less than 1.100, thereby avoiding an excessively large thickness of the first lens  110 , thus making it possible to achieve desired negative refractive power. 
     In addition, in the wide-angle lens  1000  of this embodiment, the object-to-image distance d of the wide-angle lens  1000  is 13.609 mm, and the effective focal length f of the wide-angle lens  1000  as a whole is 1.030 mm. Therefore, the following condition 9-7 is satisfied: 
       11.000&lt; d/f&lt; 15.000  (9-7)
 
     In condition 9-7, the ratio of the object-to-image distance d of the wide-angle lens  1000  to the effective focal length f of the wide-angle lens  1000  as a whole is set to be greater than 11.000, thereby enabling appropriate correction to be easily made for various aberrations, thus making it easy to achieve good optical characteristics; the ratio of the object-to-image distance d of the wide-angle lens  1000  to the effective focal length f of the wide-angle lens  1000  as a whole is set to be less than 15.000, thereby preventing the wide-angle lens  1000  from becoming excessively large while avoiding an excessively large overall length of the wide-angle lens  1000 . 
     In summary, in this embodiment, by configuring the wide-angle lens  1000  as above, as shown in  FIG. 34A  to  FIG. 36L , appropriate correction is enabled for various aberrations such as curvature of field, chromatic aberration of magnification, and coma. Moreover, the miniaturization is able to be achieved while the maximum HFOV co is expanded. 
     The disclosure has been exemplarily described above with reference to the accompanying drawings, and it is obvious that the specific implementation of the disclosure is not limited by the foregoing embodiments. 
     For example, in the foregoing embodiments, the form of the first surface  1  of the first lens  110 , the form of the third surface  3  of the second lens  120 , the form of the fifth surface  5  of the third lens  130 , the form of the seventh surface  7  of the fourth lens  140 , and the form of the twelfth surface  12  of the sixth lens  160  may be appropriately changed as needed. 
     In addition, in the foregoing embodiments, the first lens  110  and the fifth lens  150  may be composed of plastic lenses, and the second lens  120 , the third lens  130 , the fourth lens  140 , the sixth lens  160  and the seventh lens  170  may be composed of glass lenses. 
     In addition, in the foregoing embodiments, a case has been described where the wide-angle lens  1000  has seven lenses as a lens group. However, the number of the lenses of the wide-angle lens  1000  is not limited to seven, and may be set to six or less or eight or more according to actual needs. 
     Features of the above-described preferred embodiments and the modifications thereof may be combined appropriately as long as no conflict arises. 
     While preferred embodiments of the present disclosure have been described above, it is to be understood that variations and modifications will be apparent to those skilled in the art without departing from the scope and spirit of the present disclosure. The scope of the present disclosure, therefore, is to be determined solely by the following claims.