| 摘要 |
PROBLEM TO BE SOLVED: To suppress the effect of Fresnel diffraction and to increase sensitivity to ultraviolet light, even if an intensity modulation mask having a small slit width is used when a sampled grating is formed in a photosensitive core in an optical waveguide. SOLUTION: Each optical fiber 27 with a photosensitive core is put in a high pressure vessel 111, hydrogen is diffused in the optical fiber 27 in an atmosphere of high pressure hydrogen 113, the optical fiber 27 is irradiated with monochromatic incoherent light 131 of a UV lamp through slits 177 in an intensity modulation mask, the hydrogen 153 is released from the optical fiber in a heated oven 151, and the optical fiber is irradiated with coherent UV laser light 171. COPYRIGHT: (C)2005,JPO&NCIPI |
