DEVICE FOR HEAT-RESISTANCE STABILIZING TREATMENT, METHOD FOR HEAT-RESISTANCE STABILIZING TREATMENT, AND GRATING

摘要

PROBLEM TO BE SOLVED: To provide a device for heat-resistance stabilizing treatment in which only paramagnetic defects having low stability against heat are eliminated without decreasing paramagnetic defects having high stability against heat, and therefore, the heat resistance of the grating itself can be stabilized. SOLUTION: The device is equipped with a UV irradiation part 11 to irradiate a grating in quartz glass to which at least germanium is added with UV rays having <5.6 eV photon energy and <10 mW/cm2 power density during or after forming the grating. The grating has a plurality of regions having varied refractive indices formed by irradiating the quartz glass with pulse laser light.