To obtain a wavelength stabilizing unit for performing the wavelength control of a laser beam stably at high speed.
A wavelength stabilizing unit is equipped with an LD 101 which is capable of changing a laser beam in wavelength with a temperature change; a Peltier element 102 and a Peltier drive circuit 110 which control the temperature of the LD 101; a thermistor 109 which detects the temperature of the LD 101; a PD1 (104) which detects the volume of light emitted from the LD 101 as a first PD current; a PD2 (105) which detects light penetrating through an etalon filter 103 as a second PD current so as to detect a wavelength; and a memory in which a table is previously stored wherein the temperature of the LD 101, the wavelength of a laser beam emitted from the LD 101, the first PD current, and the second PD current are measured while the LD 101 is changed in temperature, and are tabled with the measurement data as a target value. A CPU 107 computes a present wavelength from outputs of the PD2 and the PD1, and the present wavelength is compared with the data stored in the memory to detect a present position for control.
KITAGAWA FUSAYASU
UTO KENICHI
Michiharu Soga
Hidetoshi Furukawa
Suzuki Kenchi
Kajinami order