Fast iterative algorithms for birefringent filter design

Abdelhak Boukharouba

doi:10.1016/j.aci.2018.08.004

Abstract

Fast iterative algorithms for designing birefringent filters with any specified spectral response are proposed. From the Jones formalism, we derive two polynomials representing the transmitted and rejected response of the filter, respectively. Once the coefficients of the filters are obtained, the orientation angle of each birefringent section and the phase shift introduced by each compensator can be determined by an iterative algorithm that gives an efficient solution to the birefringent filter design problem. Afterward, some design examples are presented to demonstrate the effectiveness of the proposed approach. In comparison with results reported in the literature, this approach provides the best performance in terms of accuracy and time complexity.

Highlights

Optical filters are most commonly used in modern optical telecommunication systems [1] and used for biomedical spectral imaging [2,3,4] such as Raman chemical imaging [5] and fluorescence microscopy applications [6]
5.1 Flat-top birefringent interleaver filter we study the case of an asymmetric flat-top birefringent interleaver synthesized using ParksMcClellan optimal equiripple finite impulse response (FIR) filter design algorithm
In this paper, iterative algorithms for designing optical FIR filters with any specified spectral response have been presented. They have been tested using different examples and it is observed that they provide exact results in many applications such as asymmetric flat-top birefringent filter, multi-channel selector, and dispersion compensation in wavelength division multiplexed (WDM) communication systems

Summary

Introduction

Optical filters are most commonly used in modern optical telecommunication systems [1] and used for biomedical spectral imaging [2,3,4] such as Raman chemical imaging [5] and fluorescence microscopy applications [6]. Interference birefringent filters are optical finite impulse response (FIR) filters based on the changes induced in the state of polarization of light by birefringent materials. They are composed of a stack of retardation plates of birefringent material placed between a polarizer and an analyser. A wide range of filters can be achieved by orienting birefringent elements in an appropriate way. They play an important role in dense wavelength division multiplexing (DWDM) systems, as in gain equalization, dispersion compensation, prefiltering, and channels add/drop applications

Methods

Discussion

Conclusion