Abstract:
A five-piece optical lens system includes, in order from the object side to the image side: a first lens element with a positive refractive power having a convex object-side surface and at least one aspheric surface; a second lens element with a negative refractive power having a concave image-side surface and at least one aspheric surface; a third lens element with a positive refractive power having at least one aspheric surface; a fourth lens element with a positive refractive power having a concave object-side surface and a convex image-side surface, and at least one aspheric surface; a fifth lens element with a negative refractive power having a concave image-side surface and at least one aspheric surface. Thereby, such a system not only can be applied to a high resolution mobile phone, but also has a wide field of view, big stop, high pixel, high resolution and low height.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    1. Field of the Invention 
         [0002]    The present invention relates to an optical lens system, and more particularly to a five-piece optical lens system. 
         [0003]    2. Description of the Prior Art 
         [0004]    In recent years, with the popularity of the mobile phone cameras, the optical lens system has become smaller in size, and 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 miniaturized optical lens systems have increasingly higher resolution. Therefore, there&#39;s an increasing demand for an imaging lens system with better image quality. 
         [0005]    Conventional miniaturized lens systems used in portable electronic products mostly consist of four lens elements, however, the resolution of the mobile phone camera has been improved rapidly. As the pixel size of electronic imaging sensors gradually becomes smaller and smaller, the system requires higher image quality, and miniaturization and high performance have become the trend of modern electronic products. The conventional optical lens system comprising four lens elements cannot satisfy the requirements of higher resolution optical lens systems. 
         [0006]    The present invention mitigates and/or obviates the aforementioned disadvantages. 
       SUMMARY OF THE INVENTION 
       [0007]    The primary objective of the present invention is to provide a five-piece optical lens system without having an excessively long total track length, the five-piece optical lens system not only can be applied to a high resolution mobile phone, but also has a wide field of view, big stop, high pixel, high resolution and low height. 
         [0008]    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 positive refractive power having a convex object-side surface, at least one of the object-side and an image-side surfaces of the first lens element being aspheric; 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, at least one of an object-side and an image-side surfaces of the third lens element being aspheric; a fourth lens element with a positive refractive power having a concave object-side surface and a convex image-side surface, at least one of the object-side and the image-side surfaces of the fourth lens element being aspheric; a fifth 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 fifth lens element being aspheric; and a stop located before the object-side surface of the first lens element (between the object side and the first lens element) or between the first lens element and the second lens element. The refractive index of the first lens element is N1, the Abbe number of the first lens element is V1, the refractive index of the second lens element is N2, the Abbe number of the second lens element is V2, and they satisfy the relations: N1&lt;1.57; V1&gt;40; N2&gt;1.57; V2&lt;40. If N1, V1, N2 and V2 satisfy the above relations, it will be favorable to correct the chromatic aberration within the system, and the material of the first and second lens elements will be appropriate, which can prevent the generation of excessive aberrations in case of a wide field of view. 
         [0009]    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: 0.3&lt;|f1|/|f2|&lt;0.9. If |f1|/|f2| satisfies the above relation, a wide field of view, big stop, high pixel and low height can be provided and the resolution can be improved evidently. Contrarily, If ∥f1|/|f2| exceeds the above range, the performance and resolution 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 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: 0.3&lt;|f1|/|f23|&lt;0.8. If |f1|/|f23| satisfies the above relation, a wide field of view, big stop, high pixel and low height can be provided and the resolution can be improved evidently. Contrarily, If |f1|/|f23| 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 second lens element is f2, the focal length of the third lens element and the fourth lens element combined is f34, and they satisfy the relation: 0.7&lt;|f2|/|f34|&lt;2.7. If |f2|/|f34| satisfies the above relation, a wide field of view, big stop, high pixel and low height can be provided and the resolution can be improved evidently. Contrarily, If |f2|/|f34| exceeds the above range, the performance and resolution 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 fourth lens element is f4, the focal length of the fifth lens element is f5, and they satisfy the relation: 0.7&lt;|f4|/|f5|&lt;1.7. If |f4|/|f5| satisfies the above relation, a wide field of view, big stop, high pixel and low height can be provided and the resolution can be improved evidently. Contrarily, If |f4|/|f5| exceeds the above range, the performance and resolution 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 and the second lens element combined is f12, the focal length of the five-piece optical lens system is f, and they satisfy the relation: 0.75&lt;|f12|/f&lt;1.25. If |f12|/f satisfies the above relation, a wide field of view, big stop, high pixel and low height can be provided and the resolution can be improved evidently. Contrarily, If |f12|/f exceeds the above range, the performance and resolution 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 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: 0.6&lt;|f123|/f&lt;0.25. If |f123|/f satisfies the above relation, a wide field of view, big stop, high pixel and low height can be provided and the resolution can be improved evidently. Contrarily, If |f123|/f exceeds the above range, the performance and resolution 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 image height perpendicular to the optical axis is IH, 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: 0.55&lt;|IH/TL|&lt;0.95. If |IH/TL| satisfies the above relation, a wide field of view, high pixel and low height can be provided and the resolution can be improved evidently. 
         [0016]    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: 0.75&lt;|f/TL|&lt;1.5. If |f/TL| satisfies the above relation, the total track length of the optical lens system can be relatively short, and the requirement of miniaturization can be satisfied. 
         [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; 
           [0022]      FIG. 3A  shows an optical lens system in accordance with a third embodiment of the present invention; 
           [0023]      FIG. 3B  shows the longitudinal spherical aberration curve, the distortion curve, and the image plane curve of the third embodiment of the present invention; 
           [0024]      FIG. 4A  shows an optical lens system in accordance with a fourth embodiment of the present invention; 
           [0025]      FIG. 4B  shows the longitudinal spherical aberration curve, the distortion curve, and the image plane curve of the fourth embodiment of the present invention; 
           [0026]      FIG. 5A  shows an optical lens system in accordance with a fifth embodiment of the present invention; 
           [0027]      FIG. 5B  shows the longitudinal spherical aberration curve, the distortion curve, and the image plane curve of the fifth embodiment of the present invention; 
           [0028]      FIG. 6A  shows an optical lens system in accordance with a sixth embodiment of the present invention; 
           [0029]      FIG. 6B  shows the longitudinal spherical aberration curve, the distortion curve, and the image plane curve of the sixth embodiment of the present invention. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0030]    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 distortion curve, and the image plane 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 A to the image side B: 
         [0031]    A stop  100 . 
         [0032]    A first lens element  110  with a positive refractive power made of plastic has a convex object-side surface  111  and a convex image-side surface  112 , and the object-side surface  111  and the image-side surface  112  of the first lens element  110  are aspheric. 
         [0033]    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. 
         [0034]    A third lens element  130  with a negative 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. 
         [0035]    A fourth lens element  140  with a positive refractive power made of plastic has a concave 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. 
         [0036]    A fifth lens element  150  with a negative refractive power made of plastic has a convex object-side surface  151  and a concave image-side surface  152 , and the object-side surface  151  and the image-side surface  152  of the fifth lens element  150  are aspheric. 
         [0037]    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. 
         [0038]    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 
                 18 
                 4 
               
               + 
               
                 Bh 
                 6 
               
               + 
               
                 Ch 
                 8 
               
               + 
               
                 Dh 
                 10 
               
               + 
               
                 Eh 
                 12 
               
               + 
               
                 Gh 
                 14 
               
               + 
               … 
             
           
         
       
     
         [0039]    wherein: 
         [0040]    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 ; 
         [0041]    k represents the conic constant; 
         [0042]    c represents the reciprocal of the radius of curvature; 
         [0043]    A, B, C, D, E, G, . . . : represent the high-order aspheric coefficients. 
         [0044]    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= 3.65.       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= 2.2. 
         [0046]    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=78°.
 
         [0047]    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]      | f 1 |/|f 2|=0.5230. 
         [0048]    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]      | f 1 |/|f 23|=0.5679. 
         [0049]    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  and the fourth lens element  140  combined is f34, and they satisfy the relation: 
         [0000]      | f 2|/| f 34|=2.2848. 
         [0050]    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]      | f 4|/| f 5|=0.9692. 
         [0051]    In the first embodiment of the present five-piece optical lens system, the focal length of the first lens element  110  and the second lens element  120  combined is f12, the focal length of the five-piece optical lens system is f, and they satisfy the relation: 
         [0000]      | f 12 |/f= 1.0343. 
         [0052]    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]      | f 123 |/f= 1.0609. 
         [0053]    In the first embodiment of the present five-piece optical lens system, the image height perpendicular to the optical axis  180  is IH, 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]      | IH/TL|= 0.8341. 
         [0054]    In the first embodiment of the present five-piece optical lens system, the focal length of the six-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|= 1.2573. 
         [0055]    In the first embodiment of the present five-piece optical lens system, the refractive index of the first lens element  110  is N1, the Abbe number of the first lens element  110  is V1, the refractive index of the second lens element  120  is N2, the Abbe number of the second lens element  120  is V2, and they satisfy the relations: 
         [0000]        N 1=1.544; 
         [0000]        V 1=56.0; 
         [0000]        N 2=1.634; 
         [0000]        V 2=23.9. 
         [0056]    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  2  and  3  represent the object-side surface  111  and the image-side surface  112  of the first lens element  110 , respectively, the surfaces  4  and  5  represent the object-side surface  121  and the image-side surface  122  of the second lens element  120 , respectively, the surfaces  6  and  7  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) = 3.65 mm, Fno = 2.2, 2ω = 78            . 
               
             
          
           
               
                   
                   
                 Curvature 
                   
                   
                   
                   
               
               
                 Surface 
                   
                 Radius 
                 Thickness 
                 Material 
                 nd 
                 vd 
               
               
                   
               
             
          
           
               
                 0 
                 Object 
                 Infinity 
                 Infinity 
                   
                   
                   
               
               
                 1 
                 Stop 
                 Infinity 
                 −0.18 
                   
                   
                   
               
               
                 2 
                 Lens 1 
                 1.560484(ASP) 
                 0.529349 
                 Plastic 
                 1.544 
                 56 
               
               
                 3 
                   
                  −61.7217(ASP)   
                 −0.02524 
                   
                   
                   
               
               
                 4 
                 Lens 2 
                 7.795235(ASP) 
                 0.24 
                 Plastic 
                 1.634 
                 23.9 
               
               
                 5 
                   
                 2.349035(ASP) 
                 0.484414 
                   
                   
                   
               
               
                 6 
                 Lens 3 
                 9.785376(ASP) 
                 0.296197 
                 Plastic 
                 1.634 
                 23.9 
               
               
                 7 
                   
                 8.125674(ASP) 
                 0.172623 
                   
                   
                   
               
               
                 8 
                 Lens 4 
                  −2.1032(ASP)   
                 0.768773 
                 Plastic 
                 1.535 
                 56 
               
               
                 9 
                   
                  −0.87066(ASP)   
                 0.363076 
                   
                   
                   
               
               
                 10 
                 Lens 5 
                 12.23327(ASP) 
                 0.384254 
                 Plastic 
                 1.535 
                 56 
               
               
                 11 
                   
                 1.128661(ASP) 
                 0.4 
                   
                   
                   
               
               
                 12 
                 IR-filter 
                 Infinity 
                 0.21 
                 Glass 
                 1.5168 
                 64.167336 
               
               
                 13 
                   
                 Infinity 
                 0.699849 
                   
                   
                   
               
               
                 14 
                 Image 
                 Infinity 
                   
                   
                   
                   
               
               
                   
               
             
          
         
       
     
         [0000]    
       
         
               
             
               
               
               
               
               
               
             
               
               
               
               
               
               
             
           
               
                 TABLE 2 
               
               
                   
               
               
                 Aspheric Coefficients 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                 Surface 
                 2 
                 3 
                 4 
                 5 
                 6 
               
               
                   
               
               
                 K = 
                 −7.03465 
                 −100 
                 49.91608 
                 −6.60061 
                 −150 
               
               
                 A = 
                 0.219293 
                 −0.07102 
                 −0.12469 
                 0.011657 
                 −0.16411 
               
               
                 B = 
                 −0.18567 
                 0.144296 
                 0.278037 
                 0.167821 
                 −0.12709 
               
               
                 C = 
                 0.133611 
                 −0.22796 
                 −0.02286 
                 0.011227 
                 0.244685 
               
               
                 D = 
                 −0.11778 
                 0.236783 
                 −0.69789 
                 −0.1806 
                 −0.21674 
               
               
                 E = 
                 0.08363 
                 −0.44906 
                 0.851034 
                 0.110964 
                 0.168086 
               
               
                 F = 
                 −0.07228 
                 0.325208 
                 −0.25057 
                 0.070388 
                 −0.058 
               
               
                   
               
             
          
           
               
                 Surface 
                 7 
                 8 
                 9 
                 10 
                 11 
               
               
                   
               
               
                 K = 
                 −38.6362 
                 0.925801 
                 −2.95677 
                 9.818339 
                 −6.62833 
               
               
                 A = 
                 −0.08048 
                 0.108739 
                 −0.10512 
                 −0.04445 
                 −0.06593 
               
               
                 B = 
                 −0.08476 
                 0.034323 
                 0.091522 
                 −0.02259 
                 0.018425 
               
               
                 C = 
                 0.105923 
                 −0.21092 
                 −0.09451 
                 0.011224 
                 −0.00657 
               
               
                 D = 
                 −0.03733 
                 0.3037 
                 0.066521 
                 −8.74E−04 
                 0.001541 
               
               
                 E = 
                 0.014924 
                 −0.17604 
                 −0.01908 
                 −1.65E−04 
                 −1.94E−04 
               
               
                 F = 
                 −0.0067 
                 0.036447 
                 0.001844 
                  2.11E−05 
                  1.00E−05 
               
               
                   
               
             
          
         
       
     
         [0057]    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 distortion curve, and the image plane 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 A to the image side B: 
         [0058]    A first lens element  210  with a positive refractive power made of plastic 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. 
         [0059]    A stop  200 . 
         [0060]    A second lens element  220  with a negative refractive power made of plastic has a convex 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. 
         [0061]    A third lens element  230  with a negative 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. 
         [0062]    A fourth lens element  240  with a positive refractive power made of plastic has a concave 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. 
         [0063]    A fifth lens element  250  with a negative refractive power made of plastic has a convex object-side surface  251  and a concave image-side surface  252 , and the object-side surface  251  and the image-side surface  252  of the fifth lens element  250  are aspheric. 
         [0064]    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. 
         [0065]    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 
                 25 
                 4 
               
               + 
               
                 Bh 
                 6 
               
               + 
               
                 Ch 
                 8 
               
               + 
               
                 Dh 
                 10 
               
               + 
               
                 Eh 
                 12 
               
               + 
               
                 Gh 
                 14 
               
               + 
               … 
             
           
         
       
     
         [0066]    wherein: 
         [0067]    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 ; 
         [0068]    k represents the conic constant; 
         [0069]    c represents the reciprocal of the radius of curvature; 
         [0070]    A, B, C, D, E, G, . . . : represent the high-order aspheric coefficients. 
         [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, and it satisfies the relation: 
         [0000]        f= 3.76.       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= 2.2. 
         [0073]    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=78°.
 
         [0074]    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]      | f 1 |/|f 2|=0.4876. 
         [0075]    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]      | f 1 |/|f 23|=0.5149. 
         [0076]    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  and the fourth lens element  240  combined is f34, and they satisfy the relation: 
         [0000]      | f 2|/| f 34|=2.3878. 
         [0077]    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]      | f 4|/| f 5|=0.9240. 
         [0078]    In the second embodiment of the present five-piece optical lens system, the focal length of the first lens element  210  and the second lens element  220  combined is f12, the focal length of the five-piece optical lens system is f, and they satisfy the relation: 
         [0000]      | f 12 |/f= 0.9676. 
         [0079]    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]      | f 123 |/f= 0.9808. 
         [0080]    In the second embodiment of the present five-piece optical lens system, the image height perpendicular to the optical axis  280  is IH, 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]      | IH/TL|= 0.8108. 
         [0081]    In the second embodiment of the present five-piece optical lens system, the focal length of the six-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|= 1.2373. 
         [0082]    In the second embodiment of the present five-piece optical lens system, the refractive index of the first lens element  210  is N1, the Abbe number of the first lens element  210  is V1, the refractive index of the second lens element  220  is N2, the Abbe number of the second lens element  220  is V2, and they satisfy the relations: 
         [0000]        N 1=1.544; 
         [0000]        V 1=56; 
         [0000]        N 2=1.632; 
         [0000]        V 2=23. 
         [0083]    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  4  and  5  represent the object-side surface  221  and the image-side surface  222  of the second lens element  220 , respectively, the surfaces  6  and  7  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) = 3.76 mm, Fno = 2.2, 2ω = 78            . 
               
             
          
           
               
                   
                   
                 Curvature 
                   
                   
                   
                   
               
               
                 Surface 
                   
                 Radius 
                 Thickness 
                 Material 
                 nd 
                 vd 
               
               
                   
               
             
          
           
               
                 0 
                 Object 
                 Infinity 
                 Infinity 
                   
                   
                   
               
               
                 1 
                 Lens 1 
                 1.409001(ASP) 
                 0.557694 
                 Plastic 
                 1.544 
                 56 
               
               
                 2 
                   
                 12.72085(ASP) 
                 0.00081 
                   
                   
                   
               
               
                 3 
                 Stop 
                 Infinity 
                 −0.077232 
                   
                   
                   
               
               
                 4 
                 Lens 2 
                 8.597133(ASP) 
                 0.257871 
                 Plastic 
                 1.632 
                 23 
               
               
                 5 
                   
                 2.572209(ASP) 
                 0.401973 
                   
                   
                   
               
               
                 6 
                 Lens 3 
                 13.80282(ASP) 
                 0.286068 
                 Plastic 
                 1.632 
                 23 
               
               
                 7 
                   
                 11.77551(ASP) 
                 0.204 
                   
                   
                   
               
               
                 8 
                 Lens 4 
                 −2.090746(ASP)   
                 0.817394 
                 Plastic 
                 1.544 
                 56 
               
               
                 9 
                   
                 −0.917573(ASP)   
                 0.07593 
                   
                   
                   
               
               
                 10 
                 Lens 5 
                 4.419141(ASP) 
                 0.531655 
                 Plastic 
                 1.535 
                 56 
               
               
                 11 
                   
                 1.016634(ASP) 
                 0.4 
                   
                   
                   
               
               
                 12 
                 IR-filter 
                 Infinity 
                 0.21 
                 Glass 
                 1.5168 
                 64.167336 
               
               
                 13 
                   
                 Infinity 
                 0.825 
                   
                   
                   
               
               
                 14 
                 Image 
                 Infinity 
                   
                   
                   
                   
               
               
                   
               
             
          
         
       
     
         [0000]    
       
         
               
             
               
               
               
               
               
               
             
               
               
               
               
               
               
             
           
               
                 TABLE 4 
               
               
                   
               
               
                 Aspheric Coefficients 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                 Surface 
                 1 
                 2 
                 4 
                 5 
                 6 
               
               
                   
               
               
                 K = 
                 −5.08906 
                 −117.339 
                 62.63813 
                 −6.99315 
                 −743.878 
               
               
                 A = 
                 0.227204 
                 −0.08056 
                 −0.11453 
                 0.020637 
                 −0.18032 
               
               
                 B = 
                 −0.17451 
                 0.120012 
                 0.239681 
                 0.213589 
                 −0.13538 
               
               
                 C = 
                 0.160468 
                 −0.23323 
                 −0.04268 
                 −0.04482 
                 0.219536 
               
               
                 D = 
                 −0.11231 
                 0.287923 
                 −0.63216 
                 −0.2501 
                 −0.26031 
               
               
                 E = 
                 0.063739 
                 −0.37575 
                 0.965873 
                 0.295571 
                 0.126041 
               
               
                 F = 
                 −0.0965 
                 0.109184 
                 −0.47291 
                 0.069364 
                 −0.07564 
               
               
                   
               
             
          
           
               
                 Surface 
                 7 
                 8 
                 9 
                 10 
                 11 
               
               
                   
               
               
                 K = 
                 −356.93 
                 0.976431 
                 −3.64558 
                 −14.4646 
                 −6.77222 
               
               
                 A = 
                 −0.09585 
                 0.106488 
                 −0.06943 
                 −0.03869 
                 −0.0561 
               
               
                 B = 
                 −0.08844 
                 0.032446 
                 0.07915 
                 −0.02331 
                 0.014293 
               
               
                 C = 
                 0.10561 
                 −0.21198 
                 −0.09651 
                 0.010919 
                 −0.00596 
               
               
                 D = 
                 −0.04173 
                 0.307385 
                 0.066702 
                 −9.30E−04 
                 0.001494 
               
               
                 E = 
                 0.010989 
                 −0.17294 
                 −0.0194 
                 −1.71E−04 
                 −2.06E−04 
               
               
                 F = 
                 −0.00138 
                 0.033784 
                 0.001671 
                  2.53E−05 
                  1.18E−05 
               
               
                   
               
             
          
         
       
     
         [0084]    Referring to  FIG. 3A , which shows a five-piece optical lens system in accordance with a third embodiment of the present invention, and  FIG. 3B  shows the longitudinal spherical aberration curves, the distortion curve, and the image plane curve of the third embodiment of the present invention. A five-piece optical lens system in accordance with the third embodiment of the present invention comprises, in order from the object side A to the image side B: 
         [0085]    A first lens element  310  with a positive refractive power made of plastic has a convex object-side surface  311  and a convex image-side surface  312 , and the object-side surface  311  and the image-side surface  312  of the first lens element  310  are aspheric. 
         [0086]    A stop  300 . 
         [0087]    A second lens element  320  with a negative refractive power made of plastic has a concave object-side surface  321  and a concave image-side surface  322 , and the object-side surface  321  and the image-side surface  322  of the second lens element  320  are aspheric. 
         [0088]    A third lens element  330  with a positive refractive power made of plastic has a concave object-side surface  331  and a convex image-side surface  332 , and the object-side surface  331  and the image-side surface  332  of the third lens element  330  are aspheric. 
         [0089]    A fourth lens element  340  with a positive refractive power made of plastic has a concave object-side surface  341  and a convex image-side surface  342 , and the object-side surface  341  and the image-side surface  342  of the fourth lens element  340  are aspheric. 
         [0090]    A fifth lens element  350  with a negative refractive power made of plastic has a convex object-side surface  351  and a concave image-side surface  352 , and the object-side surface  351  and the image-side surface  352  of the fifth lens element  350  are aspheric. 
         [0091]    An IR cut filter  360  made of glass is located between the image-side surface  352  of the fifth lens element  350  and an image plane  370  and has no influence on the focal length of the five-piece optical lens system. 
         [0092]    The equation for the aspheric surface profiles of the third embodiment is expressed as follows: 
         [0000]    
       
         
           
             z 
             = 
             
               
                 
                   ch 
                   2 
                 
                 
                   1 
                   + 
                   
                     
                       [ 
                       
                         1 
                         - 
                         
                           
                             ( 
                             
                               k 
                               + 
                               1 
                             
                             ) 
                           
                            
                           
                             c 
                             2 
                           
                            
                           
                             h 
                             2 
                           
                         
                       
                       ] 
                     
                     0.5 
                   
                 
               
               + 
               
                 Ah 
                 32 
                 4 
               
               + 
               
                 Bh 
                 6 
               
               + 
               
                 Ch 
                 8 
               
               + 
               
                 Dh 
                 10 
               
               + 
               
                 Eh 
                 12 
               
               + 
               
                 Gh 
                 14 
               
               + 
               … 
             
           
         
       
     
         [0093]    wherein: 
         [0094]    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  380 ; 
         [0095]    k represents the conic constant; 
         [0096]    c represents the reciprocal of the radius of curvature; 
         [0097]    A, B, C, D, E, G, . . . : represent the high-order aspheric coefficients. 
         [0098]    In the third 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= 3.67.       In the third 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= 2.2. 
         [0100]    In the third 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=78°.
 
         [0101]    In the third embodiment of the present five-piece optical lens system, the focal length of the first lens element  310  is f1, the focal length of the second lens element  320  is f2, and they satisfy the relation: 
         [0000]      | f 1 |/|f 2|=0.5951. 
         [0102]    In the third embodiment of the present five-piece optical lens system, the focal length of the first lens element  310  is f1, the focal length of the second lens element  320  and the third lens element  330  combined is f23, and they satisfy the relation: 
         [0000]      | f 1 |/|f 23|=0.5628. 
         [0103]    In the third embodiment of the present five-piece optical lens system, the focal length of the second lens element  320  is f2, the focal length of the third lens element  330  and the fourth lens element  340  combined is f34, and they satisfy the relation: 
         [0000]      | f 2|/| f 34|=1.4379. 
         [0104]    In the third embodiment of the present five-piece optical lens system, the focal length of the fourth lens element  340  is f4, the focal length of the fifth lens element  350  is f5, and they satisfy the relation: 
         [0000]      | f 4|/| f 5|=0.9599. 
         [0105]    In the third embodiment of the present five-piece optical lens system, the focal length of the first lens element  310  and the second lens element  320  combined is f12, the focal length of the five-piece optical lens system is f, and they satisfy the relation: 
         [0000]      | f 12 |/f= 0.9758. 
         [0106]    In the third embodiment of the present five-piece optical lens system, the focal length of the first lens element  310 , the second lens element  320  and the third lens element  330  combined is f123, the focal length of the five-piece optical lens system is f, and they satisfy the relation: 
         [0000]      | f 123 |/f= 0.9480. 
         [0107]    In the third embodiment of the present five-piece optical lens system, the image height perpendicular to the optical axis  380  is IH, the distance from the object-side surface  311  of the first lens element  310  to the image plane  370  along the optical axis  380  is TL, and they satisfy the relation: 
         [0000]      | IH/TL|= 0.8307. 
         [0108]    In the third embodiment of the present five-piece optical lens system, the focal length of the six-piece optical lens system is f, the distance from the object-side surface  311  of the first lens element  310  to the image plane  370  along the optical axis  380  is TL, and they satisfy the relation: 
         [0000]      | f/TL|= 1.2611. 
         [0109]    In the third embodiment of the present five-piece optical lens system, the refractive index of the first lens element  310  is N1, the Abbe number of the first lens element  310  is V1, the refractive index of the second lens element  320  is N2, the Abbe number of the second lens element  320  is V2, and they satisfy the relations: 
         [0000]        N 1=1.535; 
         [0000]        V 1=56; 
         [0000]        N 2=1.632; 
         [0000]        V 2=23. 
         [0110]    The detailed optical data of the third embodiment is shown in table 5, and the aspheric surface data is shown in table 6, wherein the units of the radius of curvature, the thickness and the focal length are expressed in mm. In the tables 5 and 6, the surfaces  1  and  2  represent the object-side surface  311  and the image-side surface  312  of the first lens element  310 , respectively, the surfaces  4  and  5  represent the object-side surface  321  and the image-side surface  322  of the second lens element  320 , respectively, the surfaces  6  and  7  represent the object-side surface  331  and the image-side surface  332  of the third lens element  330 , respectively, the surfaces  8  and  9  represent the object-side surface  341  and the image-side surface  342  of the fourth lens element  340 , respectively, and the surfaces  10  and  11  represent the object-side surface  351  and the image-side surface  352  of the fifth lens element  350 , respectively. 
         [0000]    
       
         
               
             
               
               
               
               
               
               
               
             
               
               
               
               
               
               
               
             
           
               
                 TABLE 5 
               
             
             
               
                   
               
               
                 (Embodiment 3) 
               
               
                 f(focal length) = 3.67 mm, Fno = 2.2, 2ω = 78            . 
               
             
          
           
               
                   
                   
                 Curvature 
                   
                   
                   
                   
               
               
                 Surface 
                   
                 Radius 
                 Thickness 
                 Material 
                 nd 
                 vd 
               
               
                   
               
             
          
           
               
                 0 
                 Object 
                 Infinity 
                 Infinity 
                   
                   
                   
               
               
                 1 
                 Lens 1 
                 1.425039(ASP) 
                 0.600755 
                 Plastic 
                 1.535 
                 56 
               
               
                 2 
                   
                  −13.9825(ASP)    
                 0.034869 
                   
                   
                   
               
               
                 3 
                 Stop 
                 Infinity 
                 −0.051359 
                   
                   
                   
               
               
                 4 
                 Lens 2 
                  −10.2631(ASP)   
                 0.24115 
                 Plastic 
                 1.632 
                 23 
               
               
                 5 
                   
                 3.546948(ASP) 
                 0.289223 
                   
                   
                   
               
               
                 6 
                 Lens 3 
                  −24.3302(ASP)   
                 0.243481 
                 Plastic 
                 1.632 
                 23 
               
               
                 7 
                   
                  −17.1989(ASP)   
                 0.291339 
                   
                   
                   
               
               
                 8 
                 Lens 4 
                  −1.88967(ASP)   
                 0.802245 
                 Plastic 
                 1.535 
                 56 
               
               
                 9 
                   
                  −0.98424(ASP)   
                 0.270639 
                   
                   
                   
               
               
                 10 
                 Lens 5 
                 4.169054(ASP) 
                 0.509484 
                 Plastic 
                 1.535 
                 56 
               
               
                 11 
                   
                 1.123768(ASP) 
                 0.432498 
                   
                   
                   
               
               
                 12 
                 IR-filter 
                 Infinity 
                 0.21 
                 Glass 
                 1.5168 
                 64.167336 
               
               
                 13 
                   
                 Infinity 
                 0.653205 
                   
                   
                   
               
               
                 14 
                 Image 
                 Infinity 
               
               
                   
               
             
          
         
       
     
         [0000]    
       
         
               
             
               
               
               
               
               
               
             
               
               
               
               
               
               
             
           
               
                 TABLE 6 
               
               
                   
               
               
                 Aspheric Coefficients 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                 Surface 
                 1 
                 2 
                 4 
                 5 
                 6 
               
               
                   
               
               
                 K = 
                 −1.25393 
                 235.4792 
                 143.2145 
                 13.81208 
                 500 
               
               
                 A = 
                 0.055968 
                 0.148624 
                 0.276214 
                 0.130146 
                 −0.15083 
               
               
                 B = 
                 0.036531 
                 −0.30728 
                 −0.41368 
                 −0.21105 
                 −0.07647 
               
               
                 C = 
                 −0.11357 
                 0.541283 
                 0.529727 
                 0.152809 
                 −0.0654 
               
               
                 D = 
                 0.186597 
                 −0.67714 
                 −0.24646 
                 0.186268 
                 −0.06612 
               
               
                 E = 
                 −0.13465 
                 0.350556 
                 0.071494 
                 −0.19352 
                 0.025326 
               
               
                   
               
             
          
           
               
                 Surface 
                 7 
                 8 
                 9 
                 10 
                 11 
               
               
                   
               
               
                 K = 
                 277.4768 
                 −0.61453 
                 −0.56198 
                 −186.983 
                 −7.41353 
               
               
                 A = 
                 −0.05925 
                 0.025956 
                 0.117385 
                 −0.09176 
                 −0.06708 
               
               
                 B = 
                 −0.05595 
                 −0.1237 
                 −0.03337 
                 0.020817 
                 0.016404 
               
               
                 C = 
                 0.018876 
                 0.164573 
                 −0.01088 
                 −4.19E−04 
                 −0.00371 
               
               
                 D = 
                 0.026344 
                 −0.05638 
                 0.020761 
                 −2.27E−04 
                  4.30E−04 
               
               
                 E = 
                 −0.00786 
                 0 
                 −3.32E−04 
                  1.49E−05 
                 −1.64E−05 
               
               
                   
               
             
          
         
       
     
         [0111]    Referring to  FIG. 4A , which shows a five-piece optical lens system in accordance with a fourth embodiment of the present invention, and  FIG. 4B  shows the longitudinal spherical aberration curves, the distortion curve, and the image plane curve of the fourth embodiment of the present invention. A five-piece optical lens system in accordance with the fourth embodiment of the present invention comprises, in order from the object side A to the image side B: 
         [0112]    A first lens element  410  with a positive refractive power made of plastic has a convex object-side surface  411  and a convex image-side surface  412 , and the object-side surface  411  and the image-side surface  412  of the first lens element  410  are aspheric. 
         [0113]    A stop  400 . 
         [0114]    A second lens element  420  with a negative refractive power made of plastic has a concave object-side surface  421  and a concave image-side surface  422 , and the object-side surface  421  and the image-side surface  422  of the second lens element  420  are aspheric. 
         [0115]    A third lens element  430  with a positive refractive power made of plastic has a concave object-side surface  431  and a convex image-side surface  432 , and the object-side surface  431  and the image-side surface  432  of the third lens element  430  are aspheric. 
         [0116]    A fourth lens element  440  with a positive refractive power made of plastic has a concave object-side surface  441  and a convex image-side surface  442 , and the object-side surface  441  and the image-side surface  442  of the fourth lens element  440  are aspheric. 
         [0117]    A fifth lens element  450  with a negative refractive power made of plastic has a convex object-side surface  451  and a concave image-side surface  452 , and the object-side surface  451  and the image-side surface  452  of the fifth lens element  450  are aspheric. 
         [0118]    An IR cut filter  460  made of glass is located between the image-side surface  452  of the fifth lens element  450  and an image plane  470  and has no influence on the focal length of the five-piece optical lens system. 
         [0119]    The equation for the aspheric surface profiles of the fourth 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 
               
               + 
               … 
             
           
         
       
     
         [0120]    wherein: 
         [0121]    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  480 ; 
         [0122]    k represents the conic constant; 
         [0123]    c represents the reciprocal of the radius of curvature; 
         [0124]    A, B, C, D, E, G, . . . : represent the high-order aspheric coefficients. 
         [0125]    In the fourth 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= 4.13.       In the fourth 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= 2.2. 
         [0127]    In the fourth 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=72°.
 
         [0128]    In the fourth embodiment of the present five-piece optical lens system, the focal length of the first lens element  410  is f1, the focal length of the second lens element  420  is f2, and they satisfy the relation: 
         [0000]      | f 1 |/|f 2|=0.6969. 
         [0129]    In the fourth embodiment of the present five-piece optical lens system, the focal length of the first lens element  410  is f1, the focal length of the second lens element  420  and the third lens element  430  combined is f23, and they satisfy the relation: 
         [0000]      | f 1 |/|f 23|=0.5256. 
         [0130]    In the fourth embodiment of the present five-piece optical lens system, the focal length of the second lens element  420  is f2, the focal length of the third lens element  430  and the fourth lens element  440  combined is f34, and they satisfy the relation: 
         [0000]      | f 2|/| f 34|=1.0029. 
         [0131]    In the fourth embodiment of the present five-piece optical lens system, the focal length of the fourth lens element  440  is f4, the focal length of the fifth lens element  450  is f5, and they satisfy the relation: 
         [0000]      | f 4|/| f 5|=1.0272. 
         [0132]    In the fourth embodiment of the present five-piece optical lens system, the focal length of the first lens element  410  and the second lens element  420  combined is f12, the focal length of the five-piece optical lens system is f, and they satisfy the relation: 
         [0000]      | f 12 |/f= 0.9423. 
         [0133]    In the fourth embodiment of the present five-piece optical lens system, the focal length of the first lens element  410 , the second lens element  420  and the third lens element  430  combined is f123, the focal length of the five-piece optical lens system is f, and they satisfy the relation: 
         [0000]      | f 123 |/f= 0.9006. 
         [0134]    In the fourth embodiment of the present five-piece optical lens system, the image height perpendicular to the optical axis  480  is IH, the distance from the object-side surface  411  of the first lens element  410  to the image plane  470  along the optical axis  480  is TL, and they satisfy the relation: 
         [0000]      | IH/TL|= 0.7374. 
         [0135]    In the fourth embodiment of the present five-piece optical lens system, the focal length of the six-piece optical lens system is f, the distance from the object-side surface  411  of the first lens element  410  to the image plane  470  along the optical axis  480  is TL, and they satisfy the relation: 
         [0000]      | f/TL|= 1.1918. 
         [0136]    In the fourth embodiment of the present five-piece optical lens system, the refractive index of the first lens element  410  is N1, the Abbe number of the first lens element  410  is V1, the refractive index of the second lens element  420  is N2, the Abbe number of the second lens element  420  is V2, and they satisfy the relations: 
         [0000]        N 1=1.535; 
         [0000]        V 1=56; 
         [0000]        N 2=1.632; 
         [0000]        V 2=23. 
         [0137]    The detailed optical data of the fourth embodiment is shown in table 7, and the aspheric surface data is shown in table 8, wherein the units of the radius of curvature, the thickness and the focal length are expressed in mm. In the tables 7 and 8, the surfaces  1  and  2  represent the object-side surface  411  and the image-side surface  412  of the first lens element  410 , respectively, the surfaces  4  and  5  represent the object-side surface  421  and the image-side surface  422  of the second lens element  420 , respectively, the surfaces  6  and  7  represent the object-side surface  431  and the image-side surface  432  of the third lens element  430 , respectively, the surfaces  8  and  9  represent the object-side surface  441  and the image-side surface  442  of the fourth lens element  440 , respectively, and the surfaces  10  and  11  represent the object-side surface  451  and the image-side surface  452  of the fifth lens element  450 , respectively. 
         [0000]    
       
         
               
             
               
               
               
               
               
               
               
             
               
               
               
               
               
               
               
             
           
               
                 TABLE 7 
               
             
             
               
                   
               
               
                 (Embodiment 4) 
               
               
                 f(focal length) = 4.13 mm, Fno = 2.2, 2ω = 72            . 
               
             
          
           
               
                 Sur- 
                   
                 Curvature 
                 Thick- 
                 Ma- 
                   
                   
               
               
                 face 
                   
                 Radius 
                 ness 
                 terial 
                 nd 
                 vd 
               
               
                   
               
             
          
           
               
                 0 
                 Object 
                 Infinity 
                 Infinity 
                   
                   
                   
               
               
                 1 
                 Lens 1 
                    1.404268 
                 0.633157 
                 Plastic 
                 1.535 
                 56 
               
               
                   
                   
                 (ASP) 
                   
                   
                   
                   
               
               
                 2 
                   
                 −20.3075 
                 0.065565 
                   
                   
                   
               
               
                   
                   
                 (ASP) 
                   
                   
                   
                   
               
               
                 3 
                 Stop 
                 Infinity 
                 0.04781 
                   
                   
                   
               
               
                 4 
                 Lens 2 
                  −9.41436 
                 0.236474 
                 Plastic 
                 1.632 
                 23 
               
               
                   
                   
                 (ASP) 
                   
                   
                   
                   
               
               
                 5 
                   
                    3.536815 
                 0.350823 
                   
                   
                   
               
               
                   
                   
                 (ASP) 
                   
                   
                   
                   
               
               
                 6 
                 Lens 3 
                 −17.3117 
                 0.326268 
                 Plastic 
                 1.632 
                 23 
               
               
                   
                   
                 (ASP) 
                   
                   
                   
                   
               
               
                 7 
                   
                 −11.9557 
                 0.32006 
                   
                   
                   
               
               
                   
                   
                 (ASP) 
                   
                   
                   
                   
               
               
                 8 
                 Lens 4 
                  −1.86311 
                 0.78298 
                 Plastic 
                 1.535 
                 56 
               
               
                   
                   
                 (ASP) 
                   
                   
                   
                   
               
               
                 9 
                   
                  −1.06311 
                 0.293306 
                   
                   
                   
               
               
                   
                   
                 (ASP) 
                   
                   
                   
                   
               
               
                 10 
                 Lens 5 
                    4.742773 
                 0.439353 
                 Plastic 
                 1.535 
                 56 
               
               
                   
                   
                 (ASP) 
                   
                   
                   
                   
               
               
                 11 
                   
                    1.260459 
                 0.432498  
                   
                   
                   
               
               
                   
                   
                 (ASP) 
                   
                   
                   
                   
               
               
                 12 
                 IR- 
                 Infinity 
                 0.21 
                 Glass 
                 1.5168 
                 64.167336 
               
               
                   
                 filter 
                   
                   
                   
                   
                   
               
               
                 13 
                   
                 Infinity 
                 0.790859 
                   
                   
                   
               
               
                 14 
                 Image 
                 Infinity 
               
               
                   
               
             
          
         
       
     
         [0000]    
       
         
               
             
               
               
               
               
               
               
             
               
               
               
               
               
               
             
           
               
                 TABLE 8 
               
               
                   
               
               
                 Aspheric Coefficients 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                 Surface 
                 1 
                 2 
                 4 
                 5 
                 6 
               
               
                   
               
               
                 K = 
                 −1.33169 
                 419.5454 
                 102.2433 
                 13.07666 
                 0 
               
               
                 A = 
                 0.055605 
                 0.164087 
                 0.283172 
                 0.164354 
                 −0.05233 
               
               
                 B = 
                 0.083407 
                 −0.30518 
                 −0.43211 
                 −0.19851 
                 −0.00193 
               
               
                 C = 
                 −0.11663 
                 0.601584 
                 0.502069 
                 0.0924 
                 −0.01973 
               
               
                 D = 
                 0.112649 
                 −0.61699 
                 −0.24476 
                 0.143403 
                 −0.02135 
               
               
                 E = 
                 −0.01969 
                 0.24602 
                 −0.02826 
                 −0.13529 
                 0.022495 
               
               
                   
               
             
          
           
               
                 Surface 
                 7 
                 8 
                 9 
                 10 
                 11 
               
               
                   
               
               
                 K = 
                 0 
                 −0.5149 
                 −0.53573 
                 −200 
                 −8.97719 
               
               
                 A = 
                 −0.013 
                 0.029173 
                 0.111875 
                 −0.11038 
                 −0.07827 
               
               
                 B = 
                 0.005104 
                 −0.149 
                 −0.04802 
                 0.022367 
                 0.017472 
               
               
                 C = 
                 0.008838 
                 0.167561 
                 −0.00444 
                 −4.90E−05 
                 −0.00362 
               
               
                 D = 
                 0.001294 
                 −0.04388 
                 0.021025 
                 −2.11E−04 
                  3.52E−04 
               
               
                 E = 
                 −0.00381 
                 0 
                 −0.00252 
                  1.81E−06 
                 −1.01E−05 
               
               
                   
               
             
          
         
       
     
         [0138]    Referring to  FIG. 5A , which shows a five-piece optical lens system in accordance with a fifth embodiment of the present invention, and  FIG. 5B  shows the longitudinal spherical aberration curves, the distortion curve, and the image plane curve of the fifth embodiment of the present invention. A five-piece optical lens system in accordance with the fifth embodiment of the present invention comprises, in order from the object side A to the image side B: 
         [0139]    A first lens element  510  with a positive refractive power made of plastic has a convex object-side surface  511  and a convex image-side surface  512 , and the object-side surface  511  and the image-side surface  512  of the first lens element  510  are aspheric. 
         [0140]    A stop  500 . 
         [0141]    A second lens element  520  with a negative refractive power made of plastic has a concave object-side surface  521  and a concave image-side surface  522 , and the object-side surface  521  and the image-side surface  522  of the second lens element  520  are aspheric. 
         [0142]    A third lens element  530  with a positive refractive power made of plastic has a convex object-side surface  531  and a convex image-side surface  532 , and the object-side surface  531  and the image-side surface  532  of the third lens element  530  are aspheric. 
         [0143]    A fourth lens element  540  with a positive refractive power made of plastic has a concave object-side surface  541  and a convex image-side surface  542 , and the object-side surface  541  and the image-side surface  542  of the fourth lens element  540  are aspheric. 
         [0144]    A fifth lens element  550  with a negative refractive power made of plastic has a convex object-side surface  551  and a concave image-side surface  552 , and the object-side surface  551  and the image-side surface  552  of the fifth lens element  550  are aspheric. 
         [0145]    An IR cut filter  560  made of glass is located between the image-side surface  552  of the fifth lens element  550  and an image plane  570  and has no influence on the focal length of the five-piece optical lens system. 
         [0146]    The equation for the aspheric surface profiles of the fifth 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 
               
               + 
               … 
             
           
         
       
     
         [0147]    wherein: 
         [0148]    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  580 ; 
         [0149]    k represents the conic constant; 
         [0150]    c represents the reciprocal of the radius of curvature; 
         [0151]    A, B, C, D, E, G, . . . : represent the high-order aspheric coefficients. 
         [0152]    In the fifth 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= 4.10.       In the fifth 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= 2.2. 
         [0154]    In the fifth 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=71.5°.
 
         [0155]    In the fifth embodiment of the present five-piece optical lens system, the focal length of the first lens element  510  is f1, the focal length of the second lens element  520  is f2, and they satisfy the relation: 
         [0000]      | f 1 |/|f 2|=0.52295. 
         [0156]    In the fifth embodiment of the present five-piece optical lens system, the focal length of the first lens element  510  is f1, the focal length of the second lens element  520  and the third lens element  530  combined is f23, and they satisfy the relation: 
         [0000]      | f 1 |/|f 23|=0.58686. 
         [0157]    In the fifth embodiment of the present five-piece optical lens system, the focal length of the second lens element  520  is f2, the focal length of the third lens element  530  and the fourth lens element  540  combined is f34, and they satisfy the relation: 
         [0000]      | f 2|/| f 34|=1.27233. 
         [0158]    In the fifth embodiment of the present five-piece optical lens system, the focal length of the fourth lens element  540  is f4, the focal length of the fifth lens element  550  is f5, and they satisfy the relation: 
         [0000]      | f 4|/| f 5|=1.54187. 
         [0159]    In the fifth embodiment of the present five-piece optical lens system, the focal length of the first lens element  510  and the second lens element  520  combined is f12, the focal length of the five-piece optical lens system is f, and they satisfy the relation: 
         [0000]      | f 12 |/f= 1.026441. 
         [0160]    In the fifth embodiment of the present five-piece optical lens system, the focal length of the first lens element  510 , the second lens element  520  and the third lens element  530  combined is f123, the focal length of the five-piece optical lens system is f, and they satisfy the relation: 
         [0000]      | f 123 |/f= 0.824081. 
         [0161]    In the fifth embodiment of the present five-piece optical lens system, the image height perpendicular to the optical axis  580  is IH, the distance from the object-side surface  511  of the first lens element  510  to the image plane  570  along the optical axis  580  is TL, and they satisfy the relation: 
         [0000]      | IH/TL|= 0.732. 
         [0162]    In the fifth embodiment of the present five-piece optical lens system, the focal length of the six-piece optical lens system is f, the distance from the object-side surface  511  of the first lens element  510  to the image plane  570  along the optical axis  580  is TL, and they satisfy the relation: 
         [0000]      | f/TL|= 1.125267. 
         [0163]    In the fifth embodiment of the present five-piece optical lens system, the refractive index of the first lens element  510  is N1, the Abbe number of the first lens element  510  is V1, the refractive index of the second lens element  520  is N2, the Abbe number of the second lens element  520  is V2, and they satisfy the relations: 
         [0000]        N 1=1.544; 
         [0000]        V 1=56; 
         [0000]        N 2=1.632; 
         [0000]        V 2=23. 
         [0164]    The detailed optical data of the fifth embodiment is shown in table 9, and the aspheric surface data is shown in table 10, wherein the units of the radius of curvature, the thickness and the focal length are expressed in mm. In the tables 9 and 10, the surfaces  1  and  2  represent the object-side surface  511  and the image-side surface  512  of the first lens element  510 , respectively, the surfaces  4  and  5  represent the object-side surface  521  and the image-side surface  522  of the second lens element  520 , respectively, the surfaces  6  and  7  represent the object-side surface  531  and the image-side surface  532  of the third lens element  530 , respectively, the surfaces  8  and  9  represent the object-side surface  541  and the image-side surface  542  of the fourth lens element  540 , respectively, and the surfaces  10  and  11  represent the object-side surface  551  and the image-side surface  552  of the fifth lens element  550 , respectively. 
         [0000]    
       
         
               
             
               
               
               
               
               
               
               
             
               
               
               
               
               
               
               
             
           
               
                 TABLE 9 
               
             
             
               
                   
               
               
                 (Embodiment 5) 
               
               
                 f(focal length) = 4.10 mm, Fno = 2.2, 2ω = 71.5            . 
               
             
          
           
               
                 Sur- 
                   
                 Curvature 
                 Thick- 
                 Ma- 
                   
                   
               
               
                 face 
                   
                 Radius 
                 ness 
                 terial 
                 nd 
                 vd 
               
               
                   
               
             
          
           
               
                 0 
                 Object 
                 Infinity 
                 Infinity 
                   
                   
                   
               
               
                 1 
                 Lens 1 
                    1.382134 
                 0.663264 
                 Plastic 
                 1.544 
                 56 
               
               
                   
                   
                 (ASP) 
                   
                   
                   
                   
               
               
                 2 
                   
                 −11.2838 
                 0.05171 
                   
                   
                   
               
               
                   
                   
                 (ASP) 
                   
                   
                   
                   
               
               
                 3 
                 Stop 
                 Infinity 
                 0.48248 
                   
                   
                   
               
               
                 4 
                 Lens 2 
                  −6.62492 
                 0.269085 
                 Plastic 
                 1.632 
                 23 
               
               
                   
                   
                 (ASP) 
                   
                   
                   
                   
               
               
                 5 
                   
                    3.131978 
                 0.348336 
                   
                   
                   
               
               
                   
                   
                 (ASP) 
                   
                   
                   
                   
               
               
                 6 
                 Lens 3 
                   13.36022 
                 0.327074 
                 Plastic 
                 1.632 
                 23 
               
               
                   
                   
                 (ASP) 
                   
                   
                   
                   
               
               
                 7 
                   
                 −18.7735 
                 0.325368 
                   
                   
                   
               
               
                   
                   
                 (ASP) 
                   
                   
                   
                   
               
               
                 8 
                 Lens 4 
                  −1.48552 
                 0.504355 
                 Plastic 
                 1.544 
                 56 
               
               
                   
                   
                 (ASP) 
                   
                   
                   
                   
               
               
                 9 
                   
                  −1.12544 
                 0.192599 
                   
                   
                   
               
               
                   
                   
                 (ASP) 
                   
                   
                   
                   
               
               
                 10 
                 Lens 5 
                    4.418314 
                 0.589184 
                 Plastic 
                 1.535 
                 56 
               
               
                   
                   
                 (ASP) 
                   
                   
                   
                   
               
               
                 11 
                   
                    1.304062 
                 0.432498 
                   
                   
                   
               
               
                   
                   
                 (ASP) 
                   
                   
                   
                   
               
               
                 12 
                 IR- 
                 Infinity 
                 0.21 
                 Glass 
                 1.5168 
                 64.167336 
               
               
                 13 
                 filter 
                 Infinity 
                 0.650027 
                   
                   
                   
               
               
                 14 
                 Image 
                 Infinity 
               
               
                   
               
             
          
         
       
     
         [0000]    
       
         
               
             
               
               
               
               
               
               
             
               
               
               
               
               
               
             
           
               
                 TABLE 10 
               
               
                   
               
               
                 Aspheric Coefficients 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                 Surface 
                 1 
                 2 
                 4 
                 5 
                 6 
               
               
                   
               
               
                 K = 
                 −1.4065 
                 111.7767 
                 55.73148 
                 8.864469 
                 −487.936 
               
               
                 A = 
                 0.052734 
                 0.130233 
                 0.246302 
                 0.118515 
                 −0.0166 
               
               
                 B = 
                 0.079827 
                 −0.19662 
                 −0.35288 
                 −0.1076 
                 −0.12878 
               
               
                 C = 
                 −0.12883 
                 0.341834 
                 0.549758 
                 0.088171 
                 0.150627 
               
               
                 D = 
                 0.130901 
                 −0.32336 
                 −0.47954 
                 0.011915 
                 −0.04331 
               
               
                 E = 
                 −0.04245 
                 0.123619 
                 0.22432 
                 −0.00897 
                 −0.0274 
               
               
                   
               
             
          
           
               
                 Surface 
                 7 
                 8 
                 9 
                 10 
                 11 
               
               
                   
               
               
                 K = 
                 −1000 
                 −0.64395 
                 −0.6986 
                 −124.267 
                 −10.1586 
               
               
                 A = 
                 −0.01558 
                 0.267164 
                 0.245819 
                 −0.09139 
                 −0.07673 
               
               
                 B = 
                 −0.04746 
                 −0.18403 
                 −0.05679 
                 0.022243 
                 0.017718 
               
               
                 C = 
                 −3.63E−04 
                 0.059801 
                 −0.01178 
                 −3.92E−04 
                 −0.00371 
               
               
                 D = 
                 0.024666 
                 −0.03999 
                 0.014741 
                 −2.68E−04 
                  3.33E−04 
               
               
                 E = 
                 −0.00469 
                 0.018742 
                 −0.00336 
                 −1.36E−06 
                 −7.90E−06 
               
               
                   
               
             
          
         
       
     
         [0165]    Referring to  FIG. 6A , which shows a five-piece optical lens system in accordance with a sixth embodiment of the present invention, and  FIG. 6B  shows the longitudinal spherical aberration curves, the distortion curve, and the image plane curve of the sixth embodiment of the present invention. A five-piece optical lens system in accordance with the sixth embodiment of the present invention comprises, in order from the object side A to the image side B: 
         [0166]    A stop  600 . 
         [0167]    A first lens element  610  with a positive refractive power made of plastic has a convex object-side surface  611  and a convex image-side surface  612 , and the object-side surface  611  and the image-side surface  612  of the first lens element  610  are aspheric. 
         [0168]    A second lens element  620  with a negative refractive power made of plastic has a concave object-side surface  621  and a concave image-side surface  622 , and the object-side surface  621  and the image-side surface  622  of the second lens element  620  are aspheric. 
         [0169]    A third lens element  630  with a negative refractive power made of plastic has a concave object-side surface  631  and a convex image-side surface  632 , and the object-side surface  631  and the image-side surface  632  of the third lens element  630  are aspheric. 
         [0170]    A fourth lens element  640  with a positive refractive power made of plastic has a concave object-side surface  641  and a convex image-side surface  642 , and the object-side surface  641  and the image-side surface  642  of the fourth lens element  640  are aspheric. 
         [0171]    A fifth lens element  650  with a negative refractive power made of plastic has a concave object-side surface  651  and a concave image-side surface  652 , and the object-side surface  651  and the image-side surface  652  of the fifth lens element  650  are aspheric. 
         [0172]    An IR cut filter  660  made of glass is located between the image-side surface  652  of the fifth lens element  650  and an image plane  670  and has no influence on the focal length of the five-piece optical lens system. 
         [0173]    The equation for the aspheric surface profiles of the sixth 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 
               
               + 
               … 
             
           
         
       
     
         [0174]    wherein: 
         [0175]    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  680 ; 
         [0176]    k represents the conic constant; 
         [0177]    c represents the reciprocal of the radius of curvature; 
         [0178]    A, B, C, D, E, G, . . . : represent the high-order aspheric coefficients. 
         [0179]    In the sixth 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= 3.29.       In the sixth 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. 
         [0181]    In the sixth 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=72°.
 
         [0182]    In the sixth embodiment of the present five-piece optical lens system, the focal length of the first lens element  610  is f1, the focal length of the second lens element  620  is f2, and they satisfy the relation: 
         [0000]      | f 1 |/|f 2|=0.4409. 
         [0183]    In the sixth embodiment of the present five-piece optical lens system, the focal length of the first lens element  610  is f1, the focal length of the second lens element  620  and the third lens element  630  combined is f23, and they satisfy the relation: 
         [0000]      | f 1 |/|f 23|=0.59426. 
         [0184]    In the sixth embodiment of the present five-piece optical lens system, the focal length of the second lens element  620  is f2, the focal length of the third lens element  630  and the fourth lens element  640  combined is f34, and they satisfy the relation: 
         [0000]      | f 2|/| f 34|=2.38843. 
         [0185]    In the sixth embodiment of the present five-piece optical lens system, the focal length of the fourth lens element  640  is f4, the focal length of the fifth lens element  650  is f5, and they satisfy the relation: 
         [0000]      | f 4|/| f 5|=1.12698. 
         [0186]    In the sixth embodiment of the present five-piece optical lens system, the focal length of the first lens element  610  and the second lens element  620  combined is f12, the focal length of the five-piece optical lens system is f, and they satisfy the relation: 
         [0000]      | f 12 |/f= 0.981891. 
         [0187]    In the sixth embodiment of the present five-piece optical lens system, the focal length of the first lens element  610 , the second lens element  620  and the third lens element  630  combined is f123, the focal length of the five-piece optical lens system is f, and they satisfy the relation: 
         [0000]      | f 123 |/f= 1.174148. 
         [0188]    In the sixth embodiment of the present five-piece optical lens system, the image height perpendicular to the optical axis  680  is IH, the distance from the object-side surface  611  of the first lens element  610  to the image plane  670  along the optical axis  680  is TL, and they satisfy the relation: 
         [0000]      | IH/TL|= 0.6283. 
         [0189]    In the sixth embodiment of the present five-piece optical lens system, the focal length of the six-piece optical lens system is f, the distance from the object-side surface  611  of the first lens element  610  to the image plane  670  along the optical axis  680  is TL, and they satisfy the relation: 
         [0000]      | f/TL|= 0.844369. 
         [0190]    In the sixth embodiment of the present five-piece optical lens system, the refractive index of the first lens element  610  is N1, the Abbe number of the first lens element  610  is V1, the refractive index of the second lens element  620  is N2, the Abbe number of the second lens element  620  is V2, and they satisfy the relations: 
         [0000]        N 1=1.544; 
         [0000]        V 1=56; 
         [0000]        N 2=1.634; 
         [0000]        V 2=23.9. 
         [0191]    The detailed optical data of the sixth embodiment is shown in table 11, and the aspheric surface data is shown in table 12, wherein the units of the radius of curvature, the thickness and the focal length are expressed in mm. In the tables 11 and 12, the surfaces  2  and  3  represent the object-side surface  611  and the image-side surface  612  of the first lens element  610 , respectively, the surfaces  4  and  5  represent the object-side surface  621  and the image-side surface  622  of the second lens element  620 , respectively, the surfaces  6  and  7  represent the object-side surface  631  and the image-side surface  632  of the third lens element  630 , respectively, the surfaces  8  and  9  represent the object-side surface  641  and the image-side surface  642  of the fourth lens element  640 , respectively, and the surfaces  10  and  11  represent the object-side surface  651  and the image-side surface  652  of the fifth lens element  650 , respectively. 
         [0000]    
       
         
               
             
               
               
               
               
               
               
               
             
               
               
               
               
               
               
               
             
           
               
                 TABLE 11 
               
             
             
               
                   
               
               
                 (Embodiment 6) 
               
               
                 f(focal length) = 3.29 mm, Fno = 2.4, 2ω = 72            . 
               
             
          
           
               
                   
                   
                 Curvature 
                   
                   
                   
                   
               
               
                 Surface 
                   
                 Radius 
                 Thickness 
                 Material 
                 nd 
                 vd 
               
               
                   
               
             
          
           
               
                 0 
                 Object 
                 Infinity 
                 Infinity 
                   
                   
                   
               
               
                 1 
                 Stop 
                 Infinity 
                 −0.14 
                   
                   
                   
               
               
                 2 
                 Lens 1 
                   1.257717(ASP)  
                 0.53791 
                 Plastic 
                 1.544 
                 56 
               
               
                 3 
                   
                 −10.6924(ASP) 
                 −0.01687 
                   
                   
                   
               
               
                 4 
                 Lens 2 
                 −6.50807(ASP) 
                 0.207915 
                 Plastic 
                 1.634 
                 23.9 
               
               
                 5 
                   
                   5.774778(ASP)  
                 0.367295 
                   
                   
                   
               
               
                 6 
                 Lens 3 
                 −3.56904(ASP) 
                 0.200937 
                 Plastic 
                 1.634 
                 23.9 
               
               
                 7 
                   
                 −5.96871(ASP) 
                 0.216628 
                   
                   
                   
               
               
                 8 
                 Lens 4 
                 −2.51481(ASP) 
                 0.670584 
                 Plastic 
                 1.535 
                 56 
               
               
                 9 
                   
                 −0.78734(ASP) 
                 0.322166 
                   
                   
                   
               
               
                 10 
                 Lens 5 
                 −2.43075(ASP) 
                 0.267001  
                 Plastic 
                 1.535 
                 56 
               
               
                 11 
                   
                   1.472389(ASP)  
                 0.201325 
                   
                   
                   
               
               
                 12 
                 IR-  
                 Infinity 
                 0.21 
                 Glass 
                 1.5168 
                 64.167336 
               
               
                 13 
                 filter 
                 Infinity 
                 0.661236 
                   
                   
                   
               
               
                 14 
                 Image 
                 Infinity 
               
               
                   
               
             
          
         
       
     
         [0000]    
       
         
               
             
               
               
               
               
               
               
             
               
               
               
               
               
               
             
           
               
                 TABLE 12 
               
               
                   
               
               
                 Aspheric Coefficients 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                 Surface 
                 2 
                 3 
                 4 
                 5 
                 6 
               
               
                   
               
               
                 K = 
                 −6.40473 
                 −327.411 
                 −7.58397 
                 −0.5696 
                 2.265561 
               
               
                 A = 
                 0.396694 
                 −0.07431 
                 0.015451 
                 0.036839 
                 −0.37053 
               
               
                 B = 
                 −0.57742 
                 0.229223 
                 0.090642 
                 0.103057 
                 −0.36481 
               
               
                 C = 
                 1.118485 
                 −1.16632 
                 1.115503 
                 0.332189 
                 1.666059 
               
               
                 D = 
                 −1.50649 
                 2.712228 
                 −6.64135 
                 −2.15986 
                 −3.11627 
               
               
                 E = 
                 0.565855 
                 −3.03995 
                 14.93765 
                 5.054825 
                 3.270529 
               
               
                 F = 
                 0.05396 
                 0.385305 
                 −11.7765 
                 −2.71382 
                 −0.19358 
               
               
                   
               
             
          
           
               
                 Surface 
                 7 
                 8 
                 9 
                 10 
                 11 
               
               
                   
               
               
                 K = 
                 5.481504 
                 2.311236 
                 −3.16194 
                 −25.3068 
                 −12.2623 
               
               
                 A = 
                 −0.20832 
                 0.048054 
                 −0.13415 
                 −0.03963 
                 −0.10933 
               
               
                 B = 
                 −0.26781 
                 0.093992 
                 0.298908 
                 −0.08476 
                 0.045783 
               
               
                 C = 
                 0.661678 
                 −1.0436 
                 −0.5219 
                 0.056217 
                 −0.02713 
               
               
                 D = 
                 −0.34404 
                 2.04679 
                 0.472168 
                 −0.00546 
                 0.010508 
               
               
                 E = 
                 0.25237 
                 −1.8395 
                 −0.18552 
                 −0.00234 
                 −0.00231 
               
               
                 F = 
                 −0.00483 
                 0.604988 
                 0.025396 
                 4.18E−04 
                 2.11E−04 
               
               
                   
               
             
          
         
       
     
         [0000]    
       
         
               
               
               
               
               
               
               
             
               
               
               
               
               
               
               
             
           
               
                 TABLE 13 
               
               
                   
               
               
                   
                 Embodiment 
                 Embodiment 
                 Embodiment 
                 Embodiment 
                 Embodiment 
                 Embodiment 
               
               
                   
                 1 
                 2 
                 3 
                 4 
                 5 
                 6 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                 |f1|/|f2| 
                 0.5230 
                 0.4876 
                 0.5951 
                 0.6969 
                 0.52295 
                 0.4409 
               
               
                 |f1|/|f23| 
                 0.5679 
                 0.5149 
                 0.5628 
                 0.5256 
                 0.58686 
                 0.59426 
               
               
                 |f2|/|f34| 
                 2.2848 
                 2.3878 
                 1.4379 
                 1.0029 
                 1.27233 
                 2.38843 
               
               
                 |f4|/|f5| 
                 0.9692 
                 0.9240 
                 0.9599 
                 1.0272 
                 1.54187 
                 1.12698 
               
               
                 |f12|/f 
                 1.0343 
                 0.9676 
                 0.9758 
                 0.9423 
                 1.026441 
                 0.981891 
               
               
                 |f123|/f 
                 1.0609 
                 0.9808 
                 0.9480 
                 0.9006 
                 0.824081 
                 1.174148 
               
               
                 |IH/TL| 
                 0.8341 
                 0.8108 
                 0.8307 
                 0.7374 
                 0.732 
                 0.6283 
               
               
                 |f/TL| 
                 1.2573 
                 1.2373 
                 1.2611 
                 1.1918 
                 1.125267 
                 0.844369 
               
               
                 N1 
                 1.544 
                 1.544 
                 1.535 
                 1.535 
                 1.544 
                 1.544 
               
               
                 N2 
                 1.634 
                 1.632 
                 1.632 
                 1.632 
                 1.632 
                 1.634 
               
               
                 V1 
                 56.0 
                 56.0 
                 56.0 
                 56.0 
                 56.0 
                 56.0 
               
               
                 V2 
                 23.9 
                 23.0 
                 23.0 
                 23.0 
                 23.0 
                 23.9 
               
               
                   
               
             
          
         
       
     
         [0192]    It is to be noted that the tables 1-12 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 13 lists the relevant data for the various embodiments of the present invention. 
         [0193]    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. 
         [0194]    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. 
         [0195]    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.