The optical receiver

PROBLEM TO BE SOLVED: To provide an optical receiver of low cost and low power consumption, which can demodulate signal light whose differential phase is deviated and modulated by orthogonal phase components by using a general purpose framer. SOLUTION: The optical receiver includes: a branch part 11 for branching an input optical signal into two optical signals; first and second delay interferometers 12A, 12B arranged on paths through which each branched light is propagated; first and second photoelectric conversion parts 13A, 13B for receiving output light from respective delay interferometers 12A, 12B; a clock reproduction circuit 14 for reproducing a clock signal on the basis of a data signal A output from one photoelectric conversion part 13A; a multiplexing part 15 for multiplexing data signals A, B output from respective photoelectric conversion parts 13A, 13B in accordance with the clock signal C; the framer 16A for framing a data signal D output from the multiplex part 15; and a delay interferometer control part 20 for resetting the operation states of respective delay interferometers 12A, 12B when frame synchronization is not taken. COPYRIGHT: (C)2008,JPO&INPIT