Abstract: A polyimide resin layer is formed on an inner surface of a metal pipe or a non-metallic pipe having a metal thin film on an inner surface to provide an optical hollow waveguide. The polyimide resin layer is transparent relative to a wavelength band of a laser light transmitted through the optical hollow waveguide. The optical hollow waveguide is fabricated by supplying solution of polyimide precursor to a hollow internal of the metal pipe or the non-metallic pipe, and heating and drying the solution to provide a polyimide resin layer. The solution-supplying step and the solution-heating and drying step are repeated to increase a thickness of the polyimide resin layer up to a predetermined value.
Type:
Grant
Filed:
January 15, 1997
Date of Patent:
March 17, 1998
Assignees:
Hitachi Cable Ltd., Mitsunobu Miyagi, J. Morita Manugacituring Corporation