Faramarz E. Seraji - Optical Communication Group, Iran Telecom Research Center, Tehran, Iran.
Fatemeh Asghari - Physics Group, Payam Noor University, Hassan Abad Br., Shahr Rey.

This paper presents a first principle analysis of the tuning characteristics of optical filter based on fiber optic ring resonator (FORR) using polarization and birefringence effects in the resonance loop. It is shown that at some operational conditions of FORR, the effects of polarization and birefringence in the resonance loop can be easy tools of tuning the filter response. We show that by simultaneously changing polarization and birefringence in the loop fiber, the filtering wavelength can be altered. In case of no polarization change and radians birefringence changes, the filtering wavelength will not alter. The result of the analysis is useful in a design of wavelength division multiplexing systems

Optical filter, FORR, tuning, polarization, birefringence