Patent ID: 11867884
Assignee: LARGAN PRECISION CO., LTD.
Field: Optics (Instruments)
Classification: CPC G | IPC G

Claim 16:
17. A photographing optical lens assembly comprising six lens elements, the six lens elements being, in order from an object side to an image side:
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; each of the six lens elements has an object-side surface towards the object side and an image-side surface towards the image side;
wherein the first lens element has positive refractive power; the second lens element has negative refractive power; at least one of the six lens elements comprises at least one inflection point;
wherein an axial distance between the second lens element and the third lens element is larger than a central thickness of the sixth lens element;
wherein an axial distance between the object-side surface of the first lens element and the image-side surface of the sixth lens element is TD, a focal length of the photographing optical lens assembly is f, a refractive index of the first lens element is N1, a refractive index of the second lens element is N2, a refractive index of the third lens element is N3, a refractive index of the fourth lens element is N4, a refractive index of the fifth lens element is N5, a refractive index of the sixth lens element is N6, a maximum of N1, N2, N3, N4, N5 and N6 is Nmax, a curvature radius of the object-side surface of the fourth lens element is R7, a curvature radius of the image-side surface of the fourth lens element is R8, an entrance pupil diameter of the photographing optical lens assembly is EPD, a maximum image height of the photographing optical lens assembly is ImgH, and the following conditions are satisfied:, 0
          .
          3
        
        ⁢
        0
      
      <
      
        T
        ⁢
        
          D
          /
          f
        
      
      <
      0.90
    
    ;
  

  
    
      
        
          
            1.639
            ≤
            
              N
              ⁢
              
                
              
              ⁢
              max
            
            <
            1.70
          
          ;
        
        ⁢
        
          

        
        -
        
          0.
          ⁢
          3
        
      
      <
      
        
          (
          
            
              R
              ⁢
              
                
              
              ⁢
              7
            
            -
            
              R
              ⁢
              
                
              
              ⁢
              8
            
          
          )
        
        /
        
          (
          
            
              R
              ⁢
              7
            
            +
            
              R
              ⁢
              8
            
          
          )
        
      
      <
      0.6
    
    ;
    and
  

  
    0.8
    <
    
      EPD
      /
      ImgH
    
    <
    
      2.0
      .