| 摘要 |
PROBLEM TO BE SOLVED: To provide a mode synchronous laser device capable of performing repetitive frequency stable pulse oscillation over a long period of time without using the electronic component of wide band characteristics or the Fabry-Perot filter of high finesse though being a high order mode synchronous laser capable of generating the pulses of a high repetitive frequency. SOLUTION: In a mode synchronous laser and a harmonic mode synchronous laser for performing modulation at a fixed frequency, when the optical path length of a resonator changes with a temperature change, the change of the envelope of a laser spectrum is caused from the spectrum spread characteristics of the optical path. The change is detected as the electric signal of the spectrum intensity difference of a modulation side band, it is amplified and then applied to an optical path length adjuster and negative feedback is applied to the change of the optical path length. By the negative feedback, the change of the optical path length by the temperature change of the laser resonator is compensated and the characteristics of the output light of the mode synchronous laser are stabilized. |
