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 six lens elements positioned sequentially from an object side to an image side. Through controlling the convex or concave shape of the surfaces and/or the refracting power of the lens elements, 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 an aperture stop, first, second, third, fourth, fifth and sixth lens elements, each of said first, second, third, fourth, fifth and sixth lens elements having an object-side surface facing toward the object side and an image-side surface facing toward the image side, wherein:
 said first lens element has positive refracting power, and said image-side surface thereof comprises a convex portion in a vicinity of a periphery of the first lens element;   said image-side surface of said second lens element comprises a concave portion in a vicinity of the optical axis;   said image-side surface of said third lens element comprises a convex portion in a vicinity of the optical axis;   said object-side surface of said fourth lens element comprises a concave portion in a vicinity of the optical axis;   said image-side surface of said fifth lens element comprises a convex portion in a vicinity of a periphery of the fifth lens element;   said image-side surface of said sixth lens element comprises a concave portion in a vicinity of the optical axis and a convex portion in a vicinity of a periphery of the sixth lens element; and   the optical imaging lens as a whole comprises only the six lens elements having refracting power.   
     
     
         2 . The optical imaging lens according to  claim 1 , wherein a central thickness of the third lens element along the optical axis is T3, an air gap between the second lens element and the third lens element along the optical axis is G23, an air gap between the fourth lens element and the fifth lens element along the optical axis is G45, and T3, G23 and G45 satisfy the equation:
     T 3/( G 23 +G 45)≦  1.9.
   
     
     
         3 . The optical imaging lens according to  claim 2 , wherein a central thickness of the first lens element along the optical axis is T1, a central thickness of the second lens element along the optical axis is T2, and T1 and T2 satisfy the equation:
   2.1 ≦T 1 /T 2.   
     
     
         4 . The optical imaging lens according to  claim 1 , wherein a central thickness of the third lens element along the optical axis is T3, an air gap between the second lens element and the third lens element along the optical axis is G23, and T3 and G23 satisfy the equation:
     T 3 /G 23≦2.3.
   
     
     
         5 . The optical imaging lens according to  claim 4 , wherein a central thickness of the first lens element along the optical axis is T1, a central thickness of the second lens element along the optical axis is T2, an air gap between the fifth lens element and the sixth lens element along the optical axis is G56, and T1, T2 and G56 satisfy the equation:
   1.4 ≦T 1/( G 56 +T 2).   
     
     
         6 . The optical imaging lens according to  claim 1 , wherein the sum of all five air gaps from the first lens element to the sixth lens element along the optical axis is Gaa, a central thickness of the third lens element along the optical axis is T3, and Gaa and T3 satisfy the equation:
   2.0 ≦Gaa/T 3≦4.5.
   
     
     
         7 . The optical imaging lens according to  claim 6 , wherein said object-side surface of said second lens element further comprises a concave portion in a vicinity of the optical axis. 
     
     
         8 . The optical imaging lens according to  claim 6 , wherein said object-side surface of said sixth lens element further comprises a convex portion in a vicinity of a periphery of the sixth lens element. 
     
     
         9 . The optical imaging lens according to  claim 6 , wherein a central thickness of the first lens element along the optical axis is T1, a central thickness of the second lens element along the optical axis is T2, and T1 and T2 satisfy the equation:
   1.9 ≦T 1 /T 2.   
     
     
         10 . The optical imaging lens according to  claim 6 , wherein a central thickness of the first lens element along the optical axis is T1, and T1 and T3 satisfy the equation:
   1.2 ≦T 1 /T 3.   
     
     
         11 . A mobile device, comprising:
 a housing; and   a photography module positioned in the housing and comprising:
 the optical imaging lens as claimed in  claim 1 ; 
 a lens barrel for positioning the optical imaging lens; 
 a module housing unit for positioning the lens barrel; and 
 an image sensor positioned at the image side of the optical imaging lens. 
   
     
     
         12 . The mobile device according to  claim 11 , wherein the module housing unit comprises a lens backseat comprising a first lens backseat and a second lens backseat, the first lens backseat is positioned close to the outside of the lens barrel and along with an axis for driving the lens barrel and the optical imaging lens positioned therein to move along the axis, and the second lens backseat is positioned along the axis and around the outside of the first lens backseat. 
     
     
         13 . The mobile device according to  claim 12 , wherein the module housing unit further comprises an image sensor base positioned between the second lens backseat and the image sensor, and the image sensor base is closed to the second lens backseat.