Fiber optics telecommunication systems (FOTS) are developing at a very high rate. The reasons for this steady growth include the availability of optical fibers with small attenuation and dispersion characteristics, invention of powerful and narrow band lasers, development of high-speed optical modulators and use of very sensitive optical receivers. Due to rapidly growing capacity requirements for FOTS high-speed high-density wavelength division multiplexing (HDWDM) systems are advancing into high data transmission rate and narrow channel spacing is used to utilize the available bandwidth more effectively [1]. In HDWDM communication systems optical wave’s polarization becomes the main effect. In principle, external electric, magnetic and electromagnetic (EM) fields can affect light transmission in optical fibers through Kerr effect, Faraday effect and Pockels effect.