Precision from every angle.

The fields with the red border are required.
    Useful Optical Formulas  
    (Prepared by : Gener Gatmaitan, 6/4/2012 for ios OpticsTM)  
      Reflection Factor              
      P = 2n/(n2 + 1)   n is the refractive index of glass        
    Refractive index of glass @ Helium (587.6nm) d line =
    Reflection Factor




    Optical Density and Transmission

      D(ג) = Log 1/T(ג)   D is the optical density and T is the transmittance      
        Optical Density (D(ג))     =    
        Transmittance (T(ג)), given D(ג)   = %  
        Transmittance (T(ג))     = %  
        Optical Density (D(ג)), given T(ג)   =    



    Abbe Number

      vd = (nd - 1) / (nF - nc) vd is the abbe number          
            nd is the refractive index at He line (587.6nm)      
            nF is the refractive index at H line (486.1nm)      
            nc is the refractive index at H line (656.3nm)      
      Refractive index at He line (587.6nm) nd =    
      Refractive index at H line (486.1nm) nF =    
      Refractive index at H line (656.3nm) nC =    
      Abbe Number     vd =    





    Temperature Conversion
      Farenheit to Celcius   oF = oC  
      Celcius to Farenheit   oC = oF  





    Glass Combination Transmittance (assume adhesive index matched to glass)
      External Transmittance of 1st glass T1 = %  
      External Transmittance of 2nd glass T2 = %  
    External tranmittance of combination





    Internal Transmittance of glass
      Kx = Ln (T1/T2) / (t1 - t2) Kx is the absorption ratio        
            T1 is the external transmittance at thickness t1      
            T2 is the external transmittance at thickness t2      
            t1 is the glass thickness with T1 transmittance      
            t2 is the glass thickness with T2 transmittance      
          τ = ℮ (thickness x Kx) τ is the Internal transmittance        
      Glass thickness     t1 = mm  
      External transmittance   T1 = %  
      Glass thickness     t2 = mm  
      External transmittance   T2 = %  
      Thickness of glass     t3 = mm, (values from t1 ~ t2)
    Internal Transmittance
    τ = %





    Glass Thickness vs Transmittance
      Thickness of glass (catalog thickness) t1 = mm  
    Refractive Index (catalog value)
    n =
      Internal Transmittance at t1 (catalog value) τ1 = %  
    Computed Reflection Factor
    P =
    Transmittance with known thickness of glass
      Thickness of given glass   t2 = mm  
      Internal Transmittance at thickness t2 τ2 = %  
      External Transmittance of glass at t2 T2 = %  
    Thickness Calculation with known glass transmittance
      Desired External transmittance of glass T3 = %  
      Computed Internal Transmittance   τ3 = %  
      Thickness of glass at transmittance T3 t3 = mm