| 摘要 |
<p>An external resonator type variable-wavelength LD light source which can compensate errors of a change in an oscillation wavelength caused by a change in an LD driving current, a change in the oscillation wavelength caused by a change in a temperature of an entire light source unit, a difference between set and actual wavelengths caused by mechanical factors to thereby ensure a wavelength reproducibility of 0.001 nm even when the LD driving current or operational temperature varies. The light source includes a light source unit temperature detection member for detecting a temperature of an entire semiconductor laser light source unit; a storage unit for storing therein oscillation wavelength changes of the semiconductor laser light source unit on the basis of a change in a driving current to the semiconductor laser, of a change in the temperature of the entire semiconductor laser light source unit detected by the light source unit temperature detection member, and of a change in an encoder output value measured by an encoder; and a wavelength change compensation member for compensating a change of the oscillation wavelength of the semiconductor laser light source unit on the basis of the oscillation wavelength changes stored in the storage unit. <IMAGE></p> |
