LIGHT SOURCE DEVICE AND WAVELENGTH CONVERSION METHOD

摘要

A ferroelectric crystal (20) has an input part for light, an output part for light and a polarization inversion structure (22). The polarization inversion structure (22) is provided between the input part and the output part. An output light source (10) makes output light incident on the input part of the ferroelectric crystal. The wavelength of the output light is converted by the polarization inversion structure (22) of the ferroelectric crystal (20). A temperature control light source (30) irradiates the polarization inversion structure (22) of the ferroelectric crystal (20) with temperature control light. The temperature control light has a wavelength that is absorbed by the ferroelectric crystal (20). A control unit (32) controls the output of the temperature control light source (30).