OPTICAL SEMICONDUCTOR DEVICE, OPTICAL COMMUNICATING SYSTEM USING THE SAME AND OPTICAL COMMUNICATION SYSTEM

摘要

PURPOSE:To provide an optical semiconductor device and an optical communication system using the same for canceling polarization dependency in the case of optical communication. CONSTITUTION:In the case of optical communication for branching a signal by using a semiconductor waveguide filter 1 on a reception side, two signals having difference wavelengths are transmitted on a transmission side while modulating semiconductor lasers 2 and 3 with the same modulated signal. Among two difference wavelengths on the transmission side, one wavelength is made coincident with the transmissive wavelength of the TE mode of the semiconductor waveguide filter 1 on the reception side, and the other wavelength is made coincident with the transmissive wavelength of the TM mode of the semiconductor waveguide filter 1. Otherwise, light is splitted into two beams and can be directly detected by two photodetectors.