Investigation of a Fabry-Perot-based optical filter for broadband multichannel communication systems

Based on Fabry-Perot structure, a multiple-channel filter is obtained in theory by changing the structure of spacer layers. This paper is concerned with the design of optical filters, based on thin-film interference, for multichannel optical communication systems with Ta2O5 and SiO2 materials for 1550 nm operation. The performance of the filter configuration is analyzed and the numerical results of the optimization parameters, such as central wavelength, 3-dB bandwidth, figure of merit and ripple in the passband, are reported. The variation of these parameters is also studied for various modified filter configurations. The angular performance of the filter is investigated in terms of spectral shift of transmittance towards shorter wavelengths. It is concluded that the width of adjacent routeways can be changed by changing the structure of spacer layers. The variation of these parameters is also studied for adding irregularly suited layers. The layer sensitivity of the ultra broadband multichannel thin-film-based optical filter, is thoroughly analysed.