Birefringent filter synthesis by use of a digital filter design algorithm.
We present an efficient method for designing birefringent filters comprising a number of birefringent sections with equal length and arbitrary orientation between two polarizers and for producing a specified spectral response in transmission. The method uses a digital filter design algorithm (i.e., the Remez algorithm) to determine an optimal polynomial approximation to obtain a specified finite impulse response, and a layer-peeling algorithm to calculate the filter structure parameters. The design procedure is demonstrated for a 14-section bandpass filter with sidelobes below -40 dB. The influence of errors in length and orientation of the birefringent sections on the filter's spectral response is also discussed.
Chu
Rui Hong
RH
University of Sydney, School of Electrical and Information Engineering, NSW, Australia.
Town
Graham
G