Abstract:
A five-piece optical lens system comprises, in order from the object side to the image side: a first lens element with a negative refractive power having a convex object-side surface; a second lens element with a negative refractive power having a concave image-side surface; a third lens element with a positive refractive power having a convex object-side surface; a stop; a fourth lens element with a positive refractive power having a convex image-side surface; a fifth lens element with a negative refractive power having a concave object-side surface, each of the second, third, fourth and fifth lens elements has at least one aspheric surface. Thereby, such a system has a wide field of view and can improve the yield rate when being applied to biomedicine, car recorder, camera or other electronic products.

Description:
BACKGROUND OF THE INVENTION 1. Field of the Invention 
       [0001]    The present invention relates to an optical lens system, and more particularly to a five-piece optical lens system. 
         [0002]    2. Description of the Prior Art 
         [0003]    The electronic sensor of a general digital camera is typically a CCD (Charge Coupled Device) or CMOS (Complementary Metal Oxide Semiconductor) sensor. Due to advances in semiconductor manufacturing, the pixel size of sensor has been reduced continuously, and optical lens systems have increasingly higher resolution. Therefore, there&#39;s an increasing demand for an imaging lens system with better image quality. 
         [0004]    However, as to the optical lens systems used in biomedicine, car recorder, camera or other electronic products, the requirement for high pixel and big stop needn&#39;t be stringent, but the problems of field of view and yield rate are needed to be solved. Conventional lens systems used in the electronic products in the above-mentioned fields mostly consist of four lens elements, however, such lens systems have some defects, such as, the field of view is small, the yield rate is low and so on. 
         [0005]    The present invention mitigates and/or obviates the aforementioned disadvantages. 
       SUMMARY OF THE INVENTION 
       [0006]    The primary objective of the present invention is to provide a five-piece optical lens system which has a wide field of view and can improve the yield rate. 
         [0007]    A five-piece optical lens system in accordance with the present invention comprises, in order from the object side to the image side: a first lens element with a negative refractive power having a convex object-side surface; a second lens element with a negative refractive power having a concave image-side surface, at least one of an object-side and the image-side surfaces of the second lens element being aspheric; a third lens element with a positive refractive power having a convex object-side surface, at least one of the object-side and an image-side surfaces of the third lens element being aspheric; a stop; a fourth lens element with a positive refractive power having a convex image-side surface, at least one of an object-side and the image-side surfaces of the fourth lens element being aspheric; and a fifth lens element with a negative refractive power having a concave object-side surface, at least one of the object-side and an image-side surfaces of the fifth lens element being aspheric. 
         [0008]    According to one aspect of the present five-piece optical lens system, the focal length of the first lens element is f1, the focal length of the second lens element is f2, and they satisfy the relation: 2.5&lt;|f1|/|f2|&lt;6. If |f1|/|f2| satisfies the above relation, a wide field of view and high yield rate can be provided. Contrarily, If |f1|/|f2| exceeds the above range, the performance of the optical lens system will be reduced, and the yield rate will be low. 
         [0009]    According to another aspect of the present five-piece optical lens system, the focal length of the second lens element is f2, the focal length of the third lens element is f3, and they satisfy the relation: 0.3&lt;|f2|/|f3|&lt;1. If |f2|/|f3| satisfies the above relation, a wide field of view and high yield rate can be provided. Contrarily, If |f2|/|f3| exceeds the above range, the performance of the optical lens system will be reduced, and the yield rate will be low. 
         [0010]    According to another aspect of the present five-piece optical lens system, the focal length of the third lens element is f3, the focal length of the fourth lens element is f4, and they satisfy the relation: 1.0&lt;|f3|/|f4|&lt;3.0. If |f3|/|f4| satisfies the above relation, a wide field of view and high yield rate can be provided. Contrarily, If |f3|/|f4| exceeds the above range, the performance and resolution of the optical lens system will be reduced, and the yield rate will be low. 
         [0011]    According to another aspect of the present five-piece optical lens system, the focal length of the fourth lens element is f4, the focal length of the fifth lens element is f5, and they satisfy the relation: |f4|/|f5|&lt;0.7. |f4|/|f5| satisfies the above relation, a wide field of view and high yield rate can be provided. Contrarily, if |f4|/|f5| exceeds the above range, the performance of the optical lens system will be reduced, and the yield rate will be low. 
         [0012]    According to another aspect of the present five-piece optical lens system, the focal length of the first lens element, the second lens element and the third lens element combined is f123, the focal length of the five-piece optical lens system is f, and they satisfy the relation: 1&lt;|f123|/|f&lt;3. If |f123|/|f| satisfies the above relation, a wide field of view and high yield rate can be provided. Contrarily, if |f123|/|f| exceeds the above range, the performance of the optical lens system will be reduced, and the yield rate will be low. 
         [0013]    According to another aspect of the present five-piece optical lens system, the focal length of the first lens element is f1, the focal length of the second lens element and the third lens element combined is f23, and they satisfy the relation: 0.5&lt;|f1|/|f23|&lt;2.3. If |f1|/|f23| satisfies the above relation, a wide field of view and high yield rate can be provided. Contrarily, if |f1|/|f23| exceeds the above range, the performance of the optical lens system will be reduced, and the yield rate will be low. 
         [0014]    According to another aspect of the present five-piece optical lens system, the focal length of the five-piece optical lens system is f, the distance from the object-side surface of the first lens element to the image plane along the optical axis is TL, and they satisfy the relation: |f/TL|&lt;0.4. If |f/TL| satisfies the above relation, a wide field of view and high yield rate can be provided. Contrarily, if |f/TL| exceeds the above range, the performance of the optical lens system will be reduced, and the yield rate will be low. 
         [0015]    According to another aspect of the present five-piece optical lens system, the first lens element is made of plastic and has a concave image-side surface, and the object-side surface and the image-side surface of the first lens element are aspheric. The second lens element is made of plastic and has a convex object-side surface, and the object-side surface and the image-side surface of the second lens element are aspheric. The third lens element is made of plastic and has a concave image-side surface, and the object-side surface and the image-side surface of the third lens element are aspheric. The fourth lens element is made of plastic and has a convex object-side surface, and the object-side surface and the image-side surface of the fourth lens element are aspheric. The fifth lens element is made of plastic and has a convex image-side surface, and the object-side surface and the image-side surface of the fifth lens element are aspheric. 
         [0016]    According to another aspect of the present five-piece optical lens system, the first lens element is made of glass and has a concave image-side surface, and the object-side surface and the image-side surface of the first lens element are aspheric. The second lens element is made of plastic and has a concave object-side surface, and the object-side surface and the image-side surface of the second lens element are aspheric. The third lens element is made of plastic and has a concave image-side surface, and the object-side surface and the image-side surface of the third lens element are aspheric. The fourth lens element is made of plastic and has a convex object-side surface, and the object-side surface and the image-side surface of the fourth lens element are aspheric. The fifth lens element is made of plastic and has a convex image-side surface, and the object-side surface and the image-side surface of the fifth lens element are aspheric. 
         [0017]    The present invention will be presented in further details from the following descriptions with the accompanying drawings, which show, for purpose of illustrations only, the preferred embodiments in accordance with the present invention. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0018]      FIG. 1A  shows an optical lens system in accordance with a first embodiment of the present invention; 
           [0019]      FIG. 1B  shows the longitudinal spherical aberration curve, the distortion curve, and the image plane curve of the first embodiment of the present invention; 
           [0020]      FIG. 2A  shows an optical lens system in accordance with a second embodiment of the present invention; 
           [0021]      FIG. 2B  shows the longitudinal spherical aberration curve, the distortion curve, and the image plane curve of the second embodiment of the present invention; 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0022]    Referring to  FIG. 1A , which shows a five-piece optical lens system in accordance with a first embodiment of the present invention, and  FIG. 1B  shows the longitudinal spherical aberration curves, the astigmatic field curves, and the distortion curve of the first embodiment of the present invention. A five-piece optical lens system in accordance with the first embodiment of the present invention comprises, in order from the object side to the image side: 
         [0023]    A first lens element  110  with a negative refractive power made of plastic has a convex object-side surface  111  and a concave image-side surface  112 , and the object-side surface  111  and the image-side surface  112  of the first lens element  110  are aspheric. 
         [0024]    A second lens element  120  with a negative refractive power made of plastic has a convex object-side surface  121  and a concave image-side surface  122 , and the object-side surface  121  and the image-side surface  122  of the second lens element  120  are aspheric. 
         [0025]    A third lens element  130  with a positive refractive power made of plastic has a convex object-side surface  131  and a concave image-side surface  132 , and the object-side surface  131  and the image-side surface  132  of the third lens element  130  are aspheric. 
         [0026]    A stop  100 . 
         [0027]    A fourth lens element  140  with a positive refractive power made of plastic has a convex object-side surface  141  and a convex image-side surface  142 , and the object-side surface  141  and the image-side surface  142  of the fourth lens element  140  are aspheric. 
         [0028]    A fifth lens element  150  with a negative refractive power made of plastic has a concave object-side surface  151  and a convex image-side surface  152 , and the object-side surface  151  and the image-side surface  152  of the fifth lens element  150  are aspheric. 
         [0029]    An IR cut filter  160  made of glass is located between the image-side surface  152  of the fifth lens element  150  and an image plane  170  and has no influence on the focal length of the five-piece optical lens system. 
         [0030]    The equation for the aspheric surface profiles of the first embodiment is expressed as follows: 
         [0000]    
       
         
           
             z 
             = 
             
               
                 
                   ch 
                   2 
                 
                 
                   1 
                   + 
                   
                     
                       [ 
                       
                         1 
                         - 
                         
                           
                             ( 
                             
                               k 
                               + 
                               1 
                             
                             ) 
                           
                            
                           
                             c 
                             2 
                           
                            
                           
                             h 
                             2 
                           
                         
                       
                       ] 
                     
                     0.5 
                   
                 
               
               + 
               
                 Ah 
                 4 
               
               + 
               
                 Bh 
                 6 
               
               + 
               
                 Ch 
                 8 
               
               + 
               
                 Dh 
                 10 
               
               + 
               
                 Eh 
                 12 
               
               + 
               
                 Gh 
                 14 
               
               + 
               … 
             
           
         
       
     
         [0031]    wherein: 
         [0032]    z represents the value of a reference position with respect to a vertex of the surface of a lens and a position with a height h along the optical axis  180 ; 
         [0033]    k represents the conic constant; 
         [0034]    c represents the reciprocal of the radius of curvature; 
         [0035]    A, B, C, D, E, G, . . . : represent the high-order aspheric coefficients. 
         [0036]    In the first embodiment of the present five-piece optical lens system, the focal length of the five-piece optical lens system is f, and it satisfies the relation: 
         [0000]      f=0.61. 
         [0037]    In the first embodiment of the present five-piece optical lens system, the f-number of the five-piece optical lens system is Fno, and it satisfies the relation: 
         [0000]      Fno=2.8. 
         [0038]    In the first embodiment of the present five-piece optical lens system, the field of view of the five-piece optical lens system is 2ω, and it satisfies the relation: 
         [0000]      2ω=141°.
 
         [0039]    In the first embodiment of the present five-piece optical lens system, the focal length of the first lens element  110  is f1, the focal length of the second lens element  120  is f2, and they satisfy the relation: 
         [0000]      |f1|/|f2|=5.0064. 
         [0040]    In the first embodiment of the present five-piece optical lens system, the focal length of the second lens element  120  is f2, the focal length of the third lens element  130  is f3, and they satisfy the relation: 
         [0000]      |f2|/|f3|=0.571. 
         [0041]    In the first embodiment of the present five-piece optical lens system, the focal length of the third lens element  130  is f3, the focal length of the fourth lens element  140  is f4, and they satisfy the relation: 
         [0000]      |f3|/|f4|=2.4828. 
         [0042]    In the first embodiment of the present five-piece optical lens system, the focal length of the fourth lens element  140  is f4, the focal length of the fifth lens element  150  is f5, and they satisfy the relation: 
         [0000]      |f4|/|f5|=0.519. 
         [0043]    In the first embodiment of the present five-piece optical lens system, the focal length of the first lens element  110 , the second lens element  120  and the third lens element  130  combined is f123, the focal length of the five-piece optical lens system is f, and they satisfy the relation: 
         [0000]      |f123|/|f|=1.907. 
         [0044]    In the first embodiment of the present five-piece optical lens system, the focal length of the first lens element  110  is f1, the focal length of the second lens element  120  and the third lens element  130  combined is f23, and they satisfy the relation: 
         [0000]      |f1|/|f23|=1.8115. 
         [0045]    In the first embodiment of the present five-piece optical lens system, the focal length of the five-piece optical lens system is f, the distance from the object-side surface  111  of the first lens element  110  to the image plane  170  along the optical axis  180  is TL, and they satisfy the relation: 
         [0000]      |f/TL|=0.1427. 
         [0046]    The detailed optical data of the first embodiment is shown in table 1, and the aspheric surface data is shown in table 2, wherein the units of the radius of curvature, the thickness and the focal length are expressed in mm. In the tables 1 and 2, the surfaces  1  and  2  represent the object-side surface  111  and the image-side surface  112  of the first lens element  110 , respectively, the surfaces  3  and  4  represent the object-side surface  121  and the image-side surface  122  of the second lens element  120 , respectively, the surfaces  5  and  6  represent the object-side surface  131  and the image-side surface  132  of the third lens element  130 , respectively, the surfaces  8  and  9  represent the object-side surface  141  and the image-side surface  142  of the fourth lens element  140 , respectively, and the surfaces  10  and  11  represent the object-side surface  151  and the image-side surface  152  of the fifth lens element  150 , respectively. 
         [0000]    
       
         
               
             
               
               
               
               
               
               
               
             
               
               
               
               
               
               
               
             
           
               
                 TABLE 1 
               
             
             
               
                   
               
               
                 (Embodiment 1) 
               
               
                 f(focal length) = 0.61 mm, Fno = 2.8, 2ω = 141°. 
               
             
          
           
               
                 Sur- 
                   
                 Curvature 
                   
                   
                   
                   
               
               
                 face 
                   
                 Radius 
                 Thickness 
                 Material 
                 nd 
                 vd 
               
               
                   
               
             
          
           
               
                 0 
                 Object 
                 Infinity 
                 500 
                   
                   
                   
               
               
                 1 
                 Lens 1 
                 4.41938(ASP) 
                 0.68489 
                 Plastic 
                 1.535 
                 56 
               
               
                 2 
                   
                 1.25089(ASP) 
                 −0.45826 
               
               
                 3 
                 Lens 2 
                 2.58748(ASP) 
                 0.29987 
                 Plastic 
                 1.565 
                 56 
               
               
                 4 
                   
                 0.31571(ASP) 
                 0.2185 
               
               
                 5 
                 Lens 3 
                 0.68931(ASP) 
                 0.72166 
                 Plastic 
                 1.634 
                 23.9 
               
               
                 6 
                   
                 3.23146(ASP) 
                 0.07748 
               
               
                 7 
                 Stop 
                 Infinity 
                 −0.0138 
               
               
                 8 
                 Lens 4 
                 0.85198(ASP) 
                 0.57669 
                 Plastic 
                 1.535 
                 56 
               
               
                 9 
                   
                 −0.2952(ASP) 
                 0.05008 
               
               
                 10 
                 Lens 5 
                 −0.5069ASP) 
                 0.31932 
                 Plastic 
                 1.634 
                 23.9 
               
               
                 11 
                   
                 −3.6892(ASP) 
                 0.46175 
               
               
                 12 
                 IR-filter 
                 Infinity 
                 0.4 
                 Glass 
                 1.5168 
                 64.1673 
               
               
                 13 
                   
                 Infinity 
                 0.045 
               
               
                 14 
                 Image 
                 Infinity 
               
               
                   
               
             
          
         
       
     
         [0000]    
       
         
               
             
               
               
             
               
               
               
               
               
               
             
               
               
             
               
               
               
               
               
               
             
           
               
                 TABLE 2 
               
               
                   
               
               
                 Aspheric Coefficients 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                   
                 Surface 
               
             
          
           
               
                   
                 1 
                 2 
                 3 
                 4 
                 5 
               
               
                   
               
               
                 K = 
                 2.272235 
                 0.383822 
                 4.908257 
                 −0.76256 
                 −0.11158 
               
               
                 A = 
                 −0.01443 
                 0.102645 
                 −0.07697 
                 −1.08 
                 −0.24825 
               
               
                 B = 
                 −0.0006 
                 −0.102 
                 0.102816 
                 −1.48816 
                 −0.67233 
               
               
                 C = 
                 0.000163 
                 −0.00875 
                 −0.04276 
                 −12.5522 
                 −0.47874 
               
               
                 D = 
                 2.6E−07 
                 0.31355 
                 −0.3153 
                 8.308509 
                 12.62426 
               
               
                   
               
             
          
           
               
                   
                 Surface 
               
             
          
           
               
                   
                 6 
                 8 
                 9 
                 10 
                 11 
               
               
                   
               
               
                 K = 
                 −360 
                 −2.01454 
                 −0.679 
                 −4.36488 
                 3.434523 
               
               
                 A = 
                 5.178583 
                 0.314421 
                 8.70778 
                 1.409741 
                 −0.52002 
               
               
                 B = 
                 −67.7769 
                 27.15316 
                 −86.3479 
                 −53.4321 
                 3.358731 
               
               
                 C = 
                 546.8936 
                 −792.666 
                 511.4431 
                 307.2865 
                 −16.5457 
               
               
                 D = 
                 517.2056 
                 10057.47 
                 −857.918 
                 −366.686 
                 46.29979 
               
               
                   
               
             
          
         
       
     
         [0047]    Referring to  FIG. 2A , which shows a five-piece optical lens system in accordance with a second embodiment of the present invention, and  FIG. 2B  shows the longitudinal spherical aberration curves, the astigmatic field curves, and the distortion curve of the second embodiment of the present invention. A five-piece optical lens system in accordance with the second embodiment of the present invention comprises, in order from the object side to the image side: 
         [0048]    A first lens element  210  with a negative refractive power made of glass has a convex object-side surface  211  and a concave image-side surface  212 , and the object-side surface  211  and the image-side surface  212  of the first lens element  210  are aspheric. 
         [0049]    A second lens element  220  with a negative refractive power made of plastic has a concave object-side surface  221  and a concave image-side surface  222 , and the object-side surface  221  and the image-side surface  222  of the second lens element  220  are aspheric. 
         [0050]    A third lens element  230  with a positive refractive power made of plastic has a convex object-side surface  231  and a concave image-side surface  232 , and the object-side surface  231  and the image-side surface  232  of the third lens element  230  are aspheric. 
         [0051]    A stop  200 . 
         [0052]    A fourth lens element  240  with a positive refractive power made of plastic has a convex object-side surface  241  and a convex image-side surface  242 , and the object-side surface  241  and the image-side surface  242  of the fourth lens element  240  are aspheric. 
         [0053]    A fifth lens element  250  with a negative refractive power made of plastic has a concave object-side surface  251  and a convex image-side surface  252 , and the object-side surface  251  and the image-side surface  252  of the fifth lens element  250  are aspheric. 
         [0054]    An IR cut filter  260  made of glass is located between the image-side surface  252  of the fifth lens element  250  and an image plane  270  and has no influence on the focal length of the five-piece optical lens system. 
         [0055]    A cover glass  290  made of glass is located between the IR cut filter  260  and the image plane  270  to protect a sensor (not shown), and has no influence on the focal length of the optical lens system with a wide field of view. 
         [0056]    The equation for the aspheric surface profiles of the second embodiment is expressed as follows: 
         [0000]    
       
         
           
             z 
             = 
             
               
                 
                   ch 
                   2 
                 
                 
                   1 
                   + 
                   
                     
                       [ 
                       
                         1 
                         - 
                         
                           
                             ( 
                             
                               k 
                               + 
                               1 
                             
                             ) 
                           
                            
                           
                             c 
                             2 
                           
                            
                           
                             h 
                             2 
                           
                         
                       
                       ] 
                     
                     0.5 
                   
                 
               
               + 
               
                 Ah 
                 4 
               
               + 
               
                 Bh 
                 6 
               
               + 
               
                 Ch 
                 8 
               
               + 
               
                 Dh 
                 10 
               
               + 
               
                 Eh 
                 12 
               
               + 
               
                 Gh 
                 14 
               
               + 
               … 
             
           
         
       
     
         [0057]    wherein: 
         [0058]    z represents the value of a reference position with respect to a vertex of the surface of a lens and a position with a height h along the optical axis  280 ; 
         [0059]    k represents the conic constant; 
         [0060]    c represents the reciprocal of the radius of curvature; 
         [0061]    A, B, C, D, E, G, . . . : represent the high-order aspheric coefficients. 
         [0062]    In the second embodiment of the present five-piece optical lens system, the focal length of the five-piece optical lens system is f, and it satisfies the relation: 
         [0000]      f=1.34. 
         [0063]    In the second embodiment of the present five-piece optical lens system, the f-number of the five-piece optical lens system is Fno, and it satisfies the relation: 
         [0000]      Fno=2.4. 
         [0064]    In the second embodiment of the present five-piece optical lens system, the field of view of the five-piece optical lens system is 2ω, and it satisfies the relation: 
         [0000]      2ω=160°.
 
         [0065]    In the second embodiment of the present five-piece optical lens system, the focal length of the first lens element  210  is f1, the focal length of the second lens element  220  is f2, and they satisfy the relation: 
         [0000]      |f1|/|f2|=3.553. 
         [0066]    In the second embodiment of the present five-piece optical lens system, the focal length of the second lens element  220  is f2, the focal length of the third lens element  230  is f3, and they satisfy the relation: 
         [0000]      |f2|/|f3|0.727. 
         [0067]    In the second embodiment of the present five-piece optical lens system, the focal length of the third lens element  230  is f3, the focal length of the fourth lens element  240  is f4, and they satisfy the relation: 
         [0000]      |f3|/|f4|=1.6495. 
         [0068]    In the second embodiment of the present five-piece optical lens system, the focal length of the fourth lens element  240  is f4, the focal length of the fifth lens element  250  is f5, and they satisfy the relation: 
         [0000]      |f4|/|f5|=0.146. 
         [0069]    In the second embodiment of the present five-piece optical lens system, the focal length of the first lens element  210 , the second lens element  220  and the third lens element  230  combined is f123, the focal length of the five-piece optical lens system is f, and they satisfy the relation: 
         [0000]      |f123|/|f|=1.852. 
         [0070]    In the second embodiment of the present five-piece optical lens system, the focal length of the first lens element  210  is f1, the focal length of the second lens element  220  and the third lens element  230  combined is f23, and they satisfy the relation: 
         [0000]      |f1|/|f23|=1.0783. 
         [0071]    In the second embodiment of the present five-piece optical lens system, the focal length of the five-piece optical lens system is f, the distance from the object-side surface  211  of the first lens element  210  to the image plane  270  along the optical axis  280  is TL, and they satisfy the relation: 
         [0000]      |f/TL|=0.0865. 
         [0072]    The detailed optical data of the second embodiment is shown in table 3, and the aspheric surface data is shown in table 4, wherein the units of the radius of curvature, the thickness and the focal length are expressed in mm. In the tables 3 and 4, the surfaces  1  and  2  represent the object-side surface  211  and the image-side surface  212  of the first lens element  210 , respectively, the surfaces  3  and  4  represent the object-side surface  221  and the image-side surface  222  of the second lens element  220 , respectively, the surfaces  5  and  6  represent the object-side surface  231  and the image-side surface  232  of the third lens element  230 , respectively, the surfaces  8  and  9  represent the object-side surface  241  and the image-side surface  242  of the fourth lens element  240 , respectively, and the surfaces  10  and  11  represent the object-side surface  251  and the image-side surface  252  of the fifth lens element  250 , respectively. 
         [0000]    
       
         
               
             
               
               
               
               
               
               
               
             
               
               
               
               
               
               
               
             
           
               
                 TABLE 3 
               
             
             
               
                   
               
               
                 (Embodiment 2) 
               
               
                 f(focal length) = 1.34 mm, Fno = 2.4, 2ω = 160°. 
               
             
          
           
               
                 Sur- 
                   
                 Curvature 
                   
                   
                   
                   
               
               
                 face 
                   
                 Radius 
                 Thickness 
                 Material 
                 nd 
                 vd 
               
               
                   
               
             
          
           
               
                 0 
                 Object 
                 Infinity 
                 Infinity 
                   
                   
                   
               
               
                 1 
                 Lens 1 
                 26.7009 
                 1.05674 
                 Glass 
                 1.729 
                 54.67 
               
               
                 2 
                   
                 3.93672 
                 2.01719 
               
               
                 3 
                 Lens 2 
                 25.7431(ASP) 
                 1.3437 
                 Plastic 
                 1.535 
                 56 
               
               
                 4 
                   
                 0.92003(ASP) 
                 0.35203 
               
               
                 5 
                 Lens 3 
                 1.55193(ASP) 
                 3.46508 
                 Plastic 
                 1.632 
                 23 
               
               
                 6 
                   
                 8.50921(ASP) 
                 0.52379 
               
               
                 7 
                 Stop 
                 Infinity 
                 −0.0728 
               
               
                 8 
                 Lens 4 
                 2.78381(ASP) 
                 1.76837 
                 Plastic 
                 1.535 
                 56 
               
               
                 9 
                   
                 −0.8902(ASP) 
                 0.08366 
               
               
                 10 
                 Lens 5 
                 −1.0545ASP) 
                 1.95215 
                 Plastic 
                 1.632 
                 23 
               
               
                 11 
                   
                 −2.1605(ASP) 
                 0.11004 
               
               
                 13 
                 IR-filter 
                 Infinity 
                 0.3 
                 Glass 
                 1.5168 
                 64.1673 
               
               
                 14 
                   
                 Infinity 
                 1.635 
               
               
                 15 
                 IR-filter 
                 Infinity 
                 0.55 
                 Glass 
                 1.5168 
                 64.1673 
               
               
                 16 
                   
                 Infinity 
                 0.455 
               
               
                 17 
                 Image 
                 Infinity 
               
               
                   
               
             
          
         
       
     
         [0000]    
       
         
               
             
               
               
               
             
               
               
               
               
               
               
             
               
               
               
             
               
               
               
               
               
               
             
           
               
                 TABLE 2 
               
               
                   
               
               
                 Aspheric Coefficients 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                   
                 Surface # 
                   
               
             
          
           
               
                   
                   
                 3 
                 4 
                 5 
                 6 
               
               
                   
                   
               
               
                   
                 k = 
                 17.91589 
                 −0.84779 
                 −0.53475 
                 −10.3908 
               
               
                   
                 A = 
                 −0.00537 
                 −0.11016 
                 −0.0326 
                 0.086261 
               
               
                   
                 B = 
                 0.000328 
                 0.021145 
                 0.006204 
                 0.000755 
               
               
                   
                 C = 
                 −5.9E−06 
                 −0.00382 
                 −0.00045 
                 −0.00361 
               
               
                   
                 D = 
                 −2.4E−07 
                 2.77E−05 
                 −0.00021 
                 0.02645 
               
               
                   
                   
               
             
          
           
               
                   
                 Surface # 
                   
               
             
          
           
               
                   
                   
                 8 
                 9 
                 10 
                 11 
               
               
                   
                   
               
               
                   
                 k = 
                 0.983636 
                 −1.08124 
                 −4.17953 
                 −8.47063 
               
               
                   
                 A = 
                 0.110855 
                 0.390382 
                 0.057261 
                 −0.05632 
               
               
                   
                 B = 
                 −0.22591 
                 −0.48338 
                 −0.205 
                 0.023317 
               
               
                   
                 C = 
                 0.343388 
                 0.242057 
                 0.059436 
                 −0.00685 
               
               
                   
                 D = 
                 −0.21757 
                 −0.03048 
                 0.0096 
                 0.000911 
               
               
                   
                   
               
             
          
         
       
     
         [0000]    
       
         
               
               
               
             
               
               
               
               
             
           
               
                   
                 TABLE 5 
               
               
                   
                   
               
               
                   
                 Embodiment 1 
                 Embodiment 2 
               
               
                   
                   
               
             
             
               
                   
               
             
          
           
               
                   
                 f 
                 0.61 
                 1.34 
               
               
                   
                 Fno 
                 2.8 
                 2.4 
               
               
                   
                 2ω 
                 141 
                 160 
               
               
                   
                 |f1|/|f2| 
                 5.0064 
                 3.553 
               
               
                   
                 |f2|/|f3| 
                 0.571 
                 0.727 
               
               
                   
                 |f3|/|f4| 
                 2.4828 
                 1.6495 
               
               
                   
                 |f4|/|f5| 
                 0.519 
                 0.146 
               
               
                   
                 |f123|/|f| 
                 1.907 
                 1.852 
               
               
                   
                 |f1|/|f23| 
                 1.8115 
                 1.0783 
               
               
                   
                 |f/TL| 
                 0.1427 
                 0.0865 
               
               
                   
                   
               
             
          
         
       
     
         [0073]    It is to be noted that the tables 1-4 show different data from the different embodiments, however, the data of the different embodiments is obtained from experiments. Therefore, any product of the same structure is deemed to be within the scope of the present invention even if it uses different data. Table 5 lists the relevant data for the various embodiments of the present invention. 
         [0074]    In the present five-piece optical lens system, the lens elements can be made of glass or plastic. If the lens elements are made of glass, there is more freedom in distributing the refractive power of the five-piece optical lens system. If the lens elements are made of plastic, the cost will be effectively reduced. 
         [0075]    In the present five-piece optical lens system, if the object-side or the image-side surface of the lens elements is convex, the object-side or the image-side surface of the lens elements in proximity of the optical axis is convex. If the object-side or the image-side surface of the lens elements is concave, the object-side or the image-side surface of the lens elements in proximity of the optical axis is concave. 
         [0076]    While we have shown and described various embodiments in accordance with the present invention, it should be clear to those skilled in the art that further embodiments may be made without departing from the scope of the present invention.