Patent ID: 7835606
Filing Date: 2010-11-16
Classification: G02B

Abstract:
1. An optical multiplexing/demultiplexing device comprising: a substrate; and first and second optical waveguides that are arranged in parallel and formed on the substrate, with one end of each of the first and second optical waveguides being configured as a first optical input/output port and the other end of each of the first and second optical waveguides being configured as a second optical input/output port, wherein the first and second optical waveguides between the first and second optical input/output ports include three or more Mach-Zehnder interferometers in series, multiplexed light comprising at least first light and second light whose wavelengths are different and which is input to either one of the first optical input/output ports is separated by wavelength and outputted from each of the second optical input/output ports of the first and second optical waveguides, the absolute value of an optical path difference ΔL with respect to light that propagates through the first and second optical waveguides in each of the Mach-Zehnder interferometers is constant, and the three or more Mach-Zehnder interferometers include at least one pair of successive Mach-Zehnder interferometers where the sum of optical path differences of the two interferometers becomes +2ΔL or −2ΔL and at least one pair of successive Mach-Zehnder interferometers where the sum of optical path differences of the two interferometers becomes 0.