| 摘要 |
PURPOSE:To prevent the lateral spread of the polarization inversion layer formed within proton exchange layers and to allow the formation of the polarization inversion layers in a short period by forming the periodic proton exchange layers on an LiTaO3 crystal and heat treating these layers to form the polarization inversion layers. CONSTITUTION:After the periodic proton exchange layer are formed on the LiTaO3 crystal 1, striped metallic films 10 are loaded on the proton exchange layers 3 and are subjected to the high-speed heating treatment by an IR heating device, by which the polarization inversion layers 4 are formed. Since the LiTaO3 substrate 1 hardly absorbs IR rays, only the metallic films 10 absorb IR rays to rapidly increase the temp. of the proton exchange layer 3 parts right under the metallic films. The heat treatment is rapidly completed by increasing the heating up speed, by which the diffusion of the proton exchange layers 3 is prevented. Since the proton exchange layers 3 are partially heated, the lateral diffusion of the proton exchange layers 3 is suppressed and the polarization inversion layers 4 of the short period are formed. |
