| 摘要 |
PROBLEM TO BE SOLVED: To facilitate the control of the free-running frequency of a laser used for an injection locking filter by making detuning between the self-running frequency of the laser and the frequency of injected light observable. SOLUTION: A reference beam, the frequency of which changes at regular time intervals, is generated by means of an optical ring circuit composed of an optical multiplexer/demultiplexer 4, an optical delay line 5-1, an optical frequency shifter 6, an optical switch 3-2, a lens 7, a semiconductor laser 8, an optical demultiplexer 9-1, an optical delay line 502, and an optical fiber 2 which couples them with each other, a normal light source 1, and an optical switch 3-2 which controls the light source 1. The frequency difference between the output light of the multiplexer/demultiplexer 4 and that of the demultiplexer 9-1 is observed, by making the outputs of the multiplexer/demultiplexer 4 and a demultiplexer 9-2 incident to a photodetector 11 through an optical demultiplexer 9-2 and an optical multiplexer 10. |
