PRODUCTION OF OPTICAL CIRCUIT ELEMENT

摘要

PURPOSE:To permit formation of a rugged pattern constituting an optical circuit element with an ordinary UV exposing device by using a material which is formed by sintering after putting the same into a sol state and gel state as an optical waveguide layer or a substrate for supporting said layer. CONSTITUTION:A sol soln. 22 which forms quartz when subjected to a gelling and sintering stage is put into a vessel 21. After the soln. is gelled, a mold 24 expanded in the size of a grating is pressed to a gel 23. The size of the gel is reduced by about half when the gel is subjected to drying and sintering in a port stage. The gel 23 transferred with the mold 24 is dried and is then sintered at a temp. lower than the temp. for finally forming the quartz to form a sintered gel 25. Ge is diffused successively onto the surface of the sintered gel 25 in a soln. prepd. by dissolving tetraethoxy germanium into ethanol to change the refractive index and to form a diffused layer 26. Sintering is further executed to form a quartz substrate 11 having the grating 13 and the optical waveguide layer 12 on the surface.