Patent ID: 6933001

Claim:
A method for manufacturing an optical filter comprising: depositing a material on a substrate; predicting a deposition stop time during the depositing of the material but prior to reaching the predicted stop time; and stopping deposition substantially at the predicted stop time, wherein said predicting comprises measuring an optical property of the deposited material at a plurality of times after the start of material deposition, and comparing the measurements to values predicted by a defined functional relationship between said optical property and time of deposition, and wherein said functional relationship defines transmittance f(t) as a function of time, and is defined as: f ⁢ ( t ) = 1 a 0 + a 1 ⁢ cos ⁢ ( a 2 ⁢ t + a 3 ) + a 4 wherein a 0 , a 1 , a 2 , a 3 , and a 4 are constant coefficients.