摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a thin film substrate for a wavelength transformation element, a substrate having a uniform composition and film thickness over a large area. <P>SOLUTION: In the first process, a first and second substrates 11, 12 are superposed in a clean atmosphere, with diffusion joining performed by a heat treatment for one hour at 400°C. Then, in the second process, the first substrate 11 is polished until the thickness becomes 20μm to obtain submicron parallelism nearly over the entirety; thus, a thin film substrate suitable for the manufacture of the wavelength transformation element is prepared. Further, in the third process, by using the thin film substrate thus prepared, a periodic polarization reversing structure is produced so that phase matching conditions are fulfilled with a 1.5μm band; thus, the thin film substrate for a wavelength transformation element is manufactured. <P>COPYRIGHT: (C)2004,JPO</p> |