| 摘要 |
PURPOSE:To increase the threshold value of the optical damage of an optical function element and to improve diffraction efficiency by forming electrodes to a part on the surface of a lithium niobate crystal substrate, etc. and implanting proton to the other region of the surface. CONSTITUTION:An optical function element using an electrooptic effect (EO) is constituted of an LiNbO3 crystal substrate 1, a diffused layer 13 of Ti in the part implanted with proton in the Ti diffused layer, comb-shaped electrodes 24, optical couplers 10, 11, etc. The element is formed by a method for manufacture consisting in including a process for forming the electrodes in part on the surface of the LiNbO3 crystal substrate or LiTaO3 crystal substrate and a process for implanting proton into the substrate in the part not covered with said electrodes. Laser light 9 is conducted from the grating optical coupler 10 to the inside of the optical waveguide of such element. |
