Mobile device and optical imaging lens thereof

Abstract

Present embodiments provide for a mobile device and an optical imaging lens thereof. The optical imaging lens comprises five lens elements positioned sequentially from an object side to an image side. Through controlling the convex or concave shape of the surfaces, the refracting power of the lens elements and parameters to meet an inequality associated with the effective focal length, the optical imaging lens shows better optical characteristics and the total length of the optical imaging lens is shortened.

What is claimed is: 
     
         1 . An optical imaging lens, sequentially from an object side to an image side along an optical axis, comprising a first lens element, a second lens element, a third lens element, a fourth lens element and a fifth lens element, each of the first, second, third, fourth and fifth lens elements having an object-side surface facing toward the object side and allowing imaging rays to pass therethrough and an image-side surface facing toward the image side and allowing the imaging rays to pass therethrough, wherein:
 the object-side surface of the third lens element comprises a concave portion in a vicinity of a periphery of the third lens element;   the image-side surface of the fourth lens element comprises a concave portion in a vicinity of the optical axis; and   the optical imaging lens as a whole has only the five lens elements,   wherein an effective focal length is EFL, a central thickness of the second lens element along the optical axis is T2, a central thickness of the third lens element along the optical axis is T3, a central thickness of the fourth lens element along the optical axis is T4, a central thickness of the fifth lens element along the optical axis is T5, an air gap between the fourth lens element and the fifth lens element along the optical axis is AG45, and EFL, T2, T3, T4, T5 and AG45 satisfy the equations:
   EFL/T5≤7.270,
 
   (T4+AG45)/T3≤2.080, and
 
   T2/T3≤1.200.
 
   
     
     
         2 . The optical imaging lens according to  claim 1 , wherein a central thickness of the first lens element along the optical axis is T1, an air gap between the third lens element and the fourth lens element along the optical axis is AG34, and T1, AG34 and T5 satisfy the equation:
   (T1+AG34)/T5≤1.971.
   
     
     
         3 . The optical imaging lens according to  claim 1 , wherein an air gap between the third lens element and the fourth lens element along the optical axis is AG34, and T3, AG34 and T5 satisfy the equation:
   (T3+AG34)/T5≤1.777.
   
     
     
         4 . The optical imaging lens according to  claim 1 , wherein a sum of all four air gaps from the first lens element to the fifth lens element along the optical axis is AAG, and AAG and T5 satisfy the equation:
   AAG/T5≤3.100.
   
     
     
         5 . The optical imaging lens according to  claim 1 , wherein a sum of thicknesses of all five lens elements along the optical axis is ALT, a central thickness of the first lens element along the optical axis is T1, and ALT and T1 satisfy the equation:
   ALT/T1≤6.574.
   
     
     
         6 . The optical imaging lens according to  claim 1 , wherein a distance between the image-side surface of the fifth lens element and an image plane along the optical axis is BFL, and BFL and T3 satisfy the equation:
   BFL/T3≤3.393.
   
     
     
         7 . The optical imaging lens according to  claim 1 , wherein an air gap between the second lens element and the third lens element along the optical axis is AG23, and T2 and AG23 satisfy the equation:
   T2/AG23≤2.500.
   
     
     
         8 . An optical imaging lens, sequentially from an object side to an image side along an optical axis, comprising a first lens element, a second lens element, a third lens element, a fourth lens element and a fifth lens element, each of the first, second, third, fourth and fifth lens elements having an object-side surface facing toward the object side and allowing imaging rays to pass therethrough and an image-side surface facing toward the image side, and allowing the imaging rays to pass therethrough, wherein:
 the fourth lens element has negative refracting power;   the image-side surface of the fourth lens element comprises a concave portion in a vicinity of the optical axis; and   the optical imaging lens as a whole has only the five lens elements,   wherein an effective focal length is EFL, a central thickness of the first lens element along the optical axis is T1, a central thickness of the fifth lens element along the optical axis is T5, an air gap between the third lens element and the fourth lens element along the optical axis is AG34, and EFL, T1, T5 and AG34 satisfy the equations:
   EFL/T5≤7.270, and
 
   (T1+AG34)/T5≤1.971.
 
   
     
     
         9 . The optical imaging lens according to  claim 8 , wherein a central thickness of the third lens element along the optical axis is T3, a central thickness of the fourth lens element along the optical axis is T4, an air gap between the fourth lens element and the fifth lens element along the optical axis is AG45, and T3, T4 and AG45 satisfy the equation:
   (T4+AG45)/T3≤2.080.
   
     
     
         10 . The optical imaging lens according to  claim 8 , wherein a central thickness of the third lens element along the optical axis is T3, a central thickness of the fourth lens element along the optical axis is T4, and T3 and T4 satisfy the equation:
   T4/T3≤1.800.
   
     
     
         11 . The optical imaging lens according to  claim 8 , wherein a central thickness of the second lens element along the optical axis is T2, a central thickness of the third lens element along the optical axis is T3, and T2 and T3 satisfy the equation:
   T2/T3<1.200.   
     
     
         12 . The optical imaging lens according to  claim 8 , wherein a sum of thicknesses of all five lens elements along the optical axis is ALT, a sum of all four air gaps from the first lens element to the fifth lens element along the optical axis is AAG, and ALT and AAG satisfy the equation:
   ALT/AAG≤3.500.
   
     
     
         13 . The optical imaging lens according to  claim 8 , wherein a central thickness of the second lens element along the optical axis is T2, an air gap between the first lens element and the second lens element along the optical axis is AG12, T2 and AG12 satisfy the equation:
   T2/AG12≤5.300.
   
     
     
         14 . The optical imaging lens according to  claim 8 , wherein a central thickness of the fourth lens element along the optical axis is T4, an air gap between the second lens element and the third lens element along the optical axis is AG23, and T4 and AG23 satisfy the equation:
   T4/AG23≤4.000.
   
     
     
         15 . An optical imaging lens, sequentially from an object side to an image side along an optical axis, comprising a first lens element, a second lens element, a third lens element, a fourth lens element and a fifth lens element, each of the first, second, third, fourth and fifth lens elements having an object-side surface facing toward the object side and allowing imaging rays to pass therethrough and an image-side surface facing toward the image side and allowing the imaging rays to pass therethrough, wherein:
 the third lens element has positive refracting power;   the image-side surface of the fourth lens element comprises a concave portion in a vicinity of the optical axis; and   the optical imaging lens as a whole has only the five lens elements,   wherein an effective focal length is EFL, a central thickness of the first lens element along the optical axis is T1, a central thickness of the fifth lens element along the optical axis is T5, an air gap between the third lens element and the fourth lens element along the optical axis is AG34, and EFL, T1, T5 and AG34 satisfy the equations:
   EFL/T5≤7.270, and
 
   (T1+AG34)/T5≤1.971.
 
   
     
     
         16 . The optical imaging lens according to  claim 15 , wherein an air gap between the second lens element and the third lens element along the optical axis is AG23, a sum of thicknesses of all five lens elements along the optical axis is ALT, and AG23 and ALT satisfy the equation:
   ALT/AG23≤10.000.
   
     
     
         17 . The optical imaging lens according to  claim 15 , wherein a central thickness of the fourth lens element along the optical axis is T4, and T4 and T5 satisfy the equation:
   0.800≤T5/T4.
   
     
     
         18 . The optical imaging lens according to  claim 15 , wherein a central thickness of the fourth lens element along the optical axis is T4, a sum of all four air gaps from the first lens element to the fifth lens element along the optical axis is AAG, and T4 and AAG satisfy the equation:
   1.700≤AAG/T4.
   
     
     
         19 . The optical imaging lens according to  claim 15 , wherein a distance between the image-side surface of the fifth lens element and an image plane along the optical axis is BFL, and BFL and T1 satisfy the equation:
   1.616≤BFL/T1≤3.682.
   
     
     
         20 . The optical imaging lens according to  claim 15 , wherein a sum of all four air gaps from the first lens element to the fifth lens element along the optical axis is AAG, and AAG and T1 satisfy the equation:
   0.945≤AAG/T1≤3.958.