| 摘要 |
PURPOSE:To control an oscillating wavelength of a laser by controlling temperature of a semiconductor laser in response to a received output of a diffracted light due to an emission of a diffraction grating. CONSTITUTION:A diffraction grating 4 is irradiated with a part of an emitted light of a semiconductor laser 1, and a diffracted light is generated. The diffracted light in which when an oscillation wavelength is increased, its output becomes small is received and detected by a detector 5 to control temperature of the laser 1 through a controller 6 and a temperature control mechanism 2, thereby setting the oscillation wavelength to a predetermined value. Thus, the oscillation wavelength of the laser is stably controlled to a predetermined constant value. If the supplying current is controlled instead of the temperature, the same result is obtained. |
