Patent ID: 11914163
Assignee: INTERDIGITAL MADISON PATENT HOLDINGS, SAS
Field: Optics (Instruments)
Classification: CPC G | IPC G

Claim 8:
9. The device of claim 8, wherein the second refractive index value of the first layer is equal to the third refractive index value of the second layer, wherein the first step structure and the third step structure have a same first height H1, and wherein the second distance d2 is described according to, (
      
        
          d
          2
        
        2
      
      )
    
    =
    
      
        -
        
          (
          
            
              d
              1
            
            2
          
          )
        
      
      -
      
        
          H
          1
        
        ·
        
          
            
              tan
              ⁢
              
                
              
              ⁢
              
                Θ
                
                  B
                  ⁢
                  1
                
                ′
              
            
            +
            
              tan
              ⁢
              
                
              
              ⁢
              
                Θ
                
                  B
                  ⁢
                  1
                
                ″
              
            
          
          2
        
      
    
  
  ,, wherein, Θ
        
          B
          ⁢
          1
        
        ′
      
      ≈
      
        
          
            
              9
              ⁢
              
                0
                ∘
              
            
            -
            
              Θ
              TIR
            
          
          2
        
        +
        
          
            Θ
            i
          
          2
        
      
    
    ,
    and
  

  
    
      
        Θ
        
          B
          ⁢
          
            
          
          ⁢
          1
        
        ″
      
      ≈
      
        
          
            
              9
              ⁢
              
                0
                ∘
              
            
            -
            
              Θ
              TIR
            
          
          2
        
        -
        
          
            Θ
            i
          
          2
        
      
    
    ,, where d1 is the first distance, and, Θ
    TIR
  
  =
  
    
      sin
      
        -
        1
      
    
    ⁡
    
      (
      
        
          n
          1
        
        
          n
          2
        
      
      ), is a critical angle of refraction, n1 is the first refractive index value of the host medium, and n2 is the second refractive index value of the first layer.