MULTILAYER FILM FILTER FOR OPTICAL MULTIPLEXER/DEMULTIPLEXER

摘要

PROBLEM TO BE SOLVED: To provide multilayer film filters which are inexpensive and have low loss and small variance in large quantities.

SOLUTION: Insertion loss is reduced to ≤-0.4 dB by setting the surface roughness of a multilayer membrane formed surface (base material A-surface) of a base material to 0.2 to 0.7 nm and the surface roughness of an antireflective membrane formed surface (base material B-surface) of the base material to 0.2 to 1.4 nm, thereby suppressing variance in insertion loss. Mass-production is attained at a low cost by setting the lower limit of the surface roughness of the base material to 0.2 mm.

COPYRIGHT: (C)2004,JPO