Optical imaging lens

Abstract

The present invention provides an optical imaging lens. The optical imaging lens comprises six lens elements positioned in an order from an object side to an image side. Through controlling the convex or concave shape of the surfaces of the lens elements and designing parameters satisfying at least one inequality, the optical imaging lens may shorten system length and promote thermal stability.

What is claimed is: 
     
         1 . An optical imaging lens, comprising a first lens element, a second lens element, a third lens element, a fourth lens element, a fifth lens element and a sixth lens element sequentially from an object side to an image side along an optical axis, each of the first, second, third, fourth, fifth and sixth lens elements having an object-side surface facing toward the object side and allowing imaging rays to pass through and an image-side surface facing toward the image side and allowing the imaging rays to pass through, wherein:
 a periphery region of the image-side surface of the second lens element is concave;   an optical axis region of the object-side surface of the fourth lens element is convex;   an optical axis region of the object-side surface of the sixth lens element is convex;   lens elements of the optical imaging lens are only the six lens elements described above; and   an abbe number of the fifth lens element is represented by V5, a refractive index of the fifth lens element is represented by n5, and the optical imaging lens satisfies the inequality:
     V 5/ n 5≤34.000.
 
   
     
     
         2 . The optical imaging lens according to  claim 1 , wherein a thickness of the first lens element along the optical axis is represented by T1, a distance from the image-side surface of the second lens element to the object-side surface of the third lens element along the optical axis is represented by G23, a distance from the image-side surface of the fourth lens element to the object-side surface of the fifth lens element along the optical axis is represented by G45, a distance from the image-side surface of the fifth lens element to the object-side surface of the sixth lens element along the optical axis is represented by G56, a thickness of the sixth lens element along the optical axis is represented by T6, and T1, G23, G45, G56 and T6 satisfy the inequality:
   ( T 1+ G 23+ G 45+ G 56)/ T 6≤3.300.
   
     
     
         3 . The optical imaging lens according to  claim 1 , wherein an optical axis region of the image-side surface of the sixth lens element is concave. 
     
     
         4 . The optical imaging lens according to  claim 1 , wherein an optical axis region of the object-side surface of the fifth lens element is concave. 
     
     
         5 . The optical imaging lens according to  claim 1 , wherein an effective focal length of the optical imaging lens is represented by EFL, a thickness of the first lens element along the optical axis is represented by T1, a distance from the image-side surface of the fourth lens element to the object-side surface of the fifth lens element along the optical axis is represented by G45, and EFL, T1 and G45 satisfy the inequality:
   EFL/( T 1+ G 45)≤5.000.
   
     
     
         6 . The optical imaging lens according to  claim 1 , wherein a distance from the image-side surface of the second lens element to the object-side surface of the third lens element along the optical axis is represented by G23, a thickness of the third lens element along the optical axis is represented by T3, a distance from the image-side surface of the third lens element to the object-side surface of the fourth lens element along the optical axis is represented by G34, a thickness of the fourth lens element along the optical axis is represented by T4, a distance from the image-side surface of the first lens element to the object-side surface of the second lens element along the optical axis is represented by G12, a thickness of the second lens element along the optical axis is represented by T2, and G23, T3, G34, T4, G12 and T2 satisfy the inequality:
   ( G 23+ T 3+ G 34+ T 4)/( G 12+ T 2)≤2.800.
   
     
     
         7 . The optical imaging lens according to  claim 1 , wherein a thickness of the sixth lens element along the optical axis is represented by T6, a distance from the image-side surface of the first lens element to the object-side surface of the second lens element along the optical axis is represented by G12, a distance from the image-side surface of the third lens element to the object-side surface of the fourth lens element along the optical axis is represented by G34, a f-number of the optical imaging lens is represented by Fno, a thickness of the first lens element along the optical axis is represented by T1, and T6, G12, G34, Fno and T1 satisfy the inequality:
   ( T 6+ G 12+ G 34)*Fno/ T 1≤6.000.
   
     
     
         8 . An optical imaging lens, comprising a first lens element, a second lens element, a third lens element, a fourth lens element, a fifth lens element and a sixth lens element sequentially from an object side to an image side along an optical axis, each of the first, second, third, fourth, fifth and sixth lens elements having an object-side surface facing toward the object side and allowing imaging rays to pass through and an image-side surface facing toward the image side and allowing the imaging rays to pass through, wherein:
 an optical axis region of the object-side surface of the third lens element is convex;   an optical axis region of the object-side surface of the fourth lens element is convex;   an optical axis region of the object-side surface of the fifth lens element is concave;   an optical axis region of the object-side surface of the sixth lens element is convex;   lens elements of the optical imaging lens are only the six lens elements described above; and   an abbe number of the fifth lens element is represented by V5, a refractive index of the fifth lens element is represented by n5, and the optical imaging lens satisfies the inequality:
     V 5/ n 5≤34.000.
 
   
     
     
         9 . The optical imaging lens according to  claim 8 , wherein a thickness of the first lens element along the optical axis is represented by T1, a distance from the image-side surface of the second lens element to the object-side surface of the third lens element along the optical axis is represented by G23, a distance from the image-side surface of the fourth lens element to the object-side surface of the fifth lens element along the optical axis is represented by G45, a distance from the image-side surface of the fifth lens element to the object-side surface of the sixth lens element along the optical axis is represented by G56, a thickness of the sixth lens element along the optical axis is represented by T6, and T1, G23, G45, G56 and T6 satisfy the inequality:
   ( T 1+ G 23+ G 45+ G 56)/ T 6≤3.300.
   
     
     
         10 . The optical imaging lens according to  claim 8 , wherein an optical axis region of the image-side surface of the sixth lens element is concave. 
     
     
         11 . The optical imaging lens according to  claim 8 , wherein a periphery region of the image-side surface of the second lens element is concave. 
     
     
         12 . The optical imaging lens according to  claim 8 , wherein an effective focal length of the optical imaging lens is represented by EFL, a thickness of the first lens element along the optical axis is represented by T1, a distance from the image-side surface of the first lens element to the object-side surface of the second lens element along the optical axis is represented by G12, and EFL, T1 and G12 satisfy the inequality:
   EFL/( T 1+ G 12)≤2.600.
   
     
     
         13 . The optical imaging lens according to  claim 8 , wherein an effective focal length of the optical imaging lens is represented by EFL, a thickness of the second lens element along the optical axis is represented by T2, a distance from the image-side surface of the second lens element to the object-side surface of the third lens element along the optical axis is represented by G23, and EFL, T2 and G23 satisfy the inequality:
   EFL/( T 2+ G 23)≤2.600.
   
     
     
         14 . The optical imaging lens according to  claim 8 , wherein a half field of view angle of the optical imaging lens is represented by HFOV, an image height of an image produced by the optical imaging lens on an image plane is represented by ImgH, and HFOV and ImgH satisfy the inequality:
   HFOV/ImgH≥20.000°/mm.
   
     
     
         15 . An optical imaging lens, comprising a first lens element, a second lens element, a third lens element, a fourth lens element, a fifth lens element and a sixth lens element sequentially from an object side to an image side along an optical axis, each of the first, second, third, fourth, fifth and sixth lens elements having an object-side surface facing toward the object side and allowing imaging rays to pass through and an image-side surface facing toward the image side and allowing the imaging rays to pass through, wherein:
 an optical axis region of the image-side surface of the second lens element is concave;   an optical axis region of the object-side surface of the fourth lens element is convex;   an optical axis region of the object-side surface of the fifth lens element is concave;   an optical axis region of the object-side surface of the sixth lens element is convex;   lens elements of the optical imaging lens are only the six lens elements described above; and   an abbe number of the fifth lens element is represented by V5, a refractive index of the fifth lens element is represented by n5, and the optical imaging lens satisfies the inequality:
     V 5/ n 5≤34.000.
 
   
     
     
         16 . The optical imaging lens according to  claim 15 , wherein a thickness of the first lens element along the optical axis is represented by T1, a distance from the image-side surface of the second lens element to the object-side surface of the third lens element along the optical axis is represented by G23, a distance from the image-side surface of the fourth lens element to the object-side surface of the fifth lens element along the optical axis is represented by G45, a distance from the image-side surface of the fifth lens element to the object-side surface of the sixth lens element along the optical axis is represented by G56, a thickness of the sixth lens element along the optical axis is represented by T6, and T1, G23, G45, G56 and T6 satisfy the inequality:
   ( T 1+ G 23+ G 45+ G 56)/ T 6≤3.300.
   
     
     
         17 . The optical imaging lens according to  claim 15 , wherein an optical axis region of the image-side surface of the sixth lens element is concave. 
     
     
         18 . The optical imaging lens according to  claim 15 , wherein an effective focal length of the optical imaging lens is represented by EFL, a thickness of the third lens element along the optical axis is represented by T3, a distance from the image-side surface of the fourth lens element to the object-side surface of the fifth lens element along the optical axis is represented by G45, and EFL, T3 and G45 satisfy the inequality:
   EFL/( T 3+ G 45)≤2.200.
   
     
     
         19 . The optical imaging lens according to  claim 15 , wherein an effective focal length of the optical imaging lens is represented by EFL, a thickness of the first lens element along the optical axis is represented by T1, a distance from the image-side surface of the fifth lens element to the object-side surface of the sixth lens element along the optical axis is represented by G56, and EFL, T1 and G56 satisfy the inequality:
   EFL/( T 1+ G 56)≤4.100.
   
     
     
         20 . The optical imaging lens according to  claim 15 , wherein a thickness of the sixth lens element along the optical axis is represented by T6, a distance from the image-side surface of the third lens element to the object-side surface of the fourth lens element along the optical axis is represented by G34, a distance from the image-side surface of the fifth lens element to the object-side surface of the sixth lens element along the optical axis is represented by G56, a distance from the image-side surface of the second lens element to the object-side surface of the third lens element along the optical axis is represented by G23, and T6, G34, G56 and G23 satisfy the inequality:
   ( T 6+ G 34+ G 56)/ G 23≤2.400.