Patent ID: 11971676
Assignee: KYOCERA DOCUMENT SOLUTIONS INC.
Field: Optics (Instruments)
Classification: CPC G | IPC G

Claim 1:
2. The image density measurement method according to claim 1, wherein
the processor derives the test image density by applying the plurality of unit density values to a calculation expression below or to an alternative expression equivalent to the calculation expression below,, [
     
      Expression
      ⁢
         
      1
     
     ]
    
   
   
    
   
  
  
   
    
     IDT
     =
     
      
       
        
         ∑
         
          t
          =
          1
         
         a
        
        
         (
         
          i
          ·
          
           ID
           ⁡
           (
           i
           )
          
         
         )
        
       
       +
       
        
         ∑
         
          i
          =
          
           a
           -
           1
          
         
         b
        
        
         (
         
          a
          ·
          
           ID
           ⁡
           (
           i
           )
          
         
         )
        
       
       +
       
        
         ∑
         
          i
          =
          
           b
           +
           1
          
         
         n
        
        
         (
         
          
           (
           
            a
            +
            b
            -
            1
           
           )
          
          ·
          
           ID
           ⁡
           (
           i
           )
          
         
         )
        
       
      
      N
     
    
   
   
    
     (
     1
     )
    
   
  
 

 
  
   n
   =
   
    a
    +
    b
    -
    1
   
  
  ,
  
   N
   =
   
    a
    ·
    b
   
  
 

where, in the calculation expression, IDT represents the test image density, i represents an identification number of the plurality of unit areas, ID(i) represents a density value corresponding to an i-th unit area out of the plurality of unit density values, a represents the first constant obtained by dividing a shorter one of the two target lengths by the unit length, and b represents the second constant obtained by dividing a longer one of the two target lengths by the unit length.