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.
© 2002 Optical Society of America
(070.6020) Fourier optics and signal processing : Continuous optical signal processing
(120.2440) Instrumentation, measurement, and metrology : Filters
(230.0230) Optical devices : Optical devices
(260.1440) Physical optics : Birefringence
Rui Hong Chu and Graham Town, "Birefringent Filter Synthesis by Use of a Digital Filter Design Algorithm," Appl. Opt. 41, 3412-3418 (2002)