| 摘要 |
PROBLEM TO BE SOLVED: To provide an optical switch which has a high extinction ratio over a wide range, with an insertion loss less dependent on wavelengths and will not degrade the extinction ratio and insertion loss, even if there are variations when manufacturing the optical branching couplers composing the circuit. SOLUTION: In the optical switch built by cascade connecting the Mach-Zehnder interferometers, consisting of two optical branching couplers and two arm optical waveguides connecting them and phase adjusters provided to the arm optical wave guides, the optical branching couplers, constituting the Mach Zehnder interferometers, are made in two or more kinds. Accordingly, even if transmissivity errors are caused in either one of the optical branching couplers due to the variations in manufacturing, the other one is hard to make the same transmissivity errors since its kind is different. COPYRIGHT: (C)2007,JPO&INPIT |
