| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a tunable filter which enables selection of arbitrary wavelength and is high-speed despite of a simple configuration. <P>SOLUTION: In an optical circuit of Mach-Zehnder interferometer, physical lengths of the parts (that is, branched waveguide) located between 3-dB couplers 13, 14 of input/output waveguides 11, 12 are equal to each other. Ring resonators 23, 24 having different physical lengths to each other are connected with the branched waveguide by optical couplers 21, 22 and the current injection and the voltage application to the ring resonators 23, 24 are made possible by electrodes 25, 26. The tunable filter F1 having such a configuration is allowed to transmit only signal light of a wavelength having a specified frequency interval (FSR). In addition, by changing the value of injection current and applied voltage, the outputted wavelength can be made variable. <P>COPYRIGHT: (C)2004,JPO</p> |
