| 摘要 |
PROBLEM TO BE SOLVED: To provide quartz glass for forming grating, which is easy to form grating and in which the light induced refractive index change occurs easily and effectively by irradiating it with an ultraviolet ray having a wavelength of longer wavelength side(low photon energy side) than the conventional wavelength. SOLUTION: It is possible to rapidly increase the absorption coefficient at the photon energy of about 4 eV and to form high absorption band at the high photon energy range of >4 eV, in the absorption characteristic prescribed by the relation of the photon energy and the absorption coefficient, by co-doping Sn in addition to Ge. The induction of GeE' center is accelerated by co-doping Sn into quartz glass for forming grating under an oxygen-deficient environment. |
