| 摘要 |
PROBLEM TO BE SOLVED: To realize a very small optical multiplexer/demultiplexer in spectrum spread and superior in wavelength flatness of a loss in a wavelength pass region. SOLUTION: The optical multiplexer/demultiplexer, which is composed of plural optical multiplexing/demultiplexing circuits having an optical path including a waveguide and where respective multiplexing/demultiplexing circuits is provided with first to fourth ports, the first port being connected to a second port via the optical path including a third port, the fourth port and the waveguide, and an outputting optical path is different according to a port, to which an optical signal having a prescribed wavelength is inputted. One of the ports of the first step multiplexing/demultiplexing circuit is connected to one of the ports of the second multiplexing/demultiplexing circuit, and when the signal is inputted to the other port of the first step multiplexing/ demultiplexing circuit, the optical path of the first step multiplexing/ demultiplexing circuit, through which the signal passes is provided with a spectrum spread characteristics inverse to that of the optical path of the second step multiplexing/demultiplexing circuit. |
