ARRAY WAVEGUIDE TYPE WAVELENGTH MULTIPLEXER -DEMULTIPLEXER

摘要

PROBLEM TO BE SOLVED: To provide an array waveguide type wavelength multiplexer -demultiplexer which can realize a flat spectrum with low loss and whose transmission characteristic is variable. SOLUTION: The change in a light focusing position at an output end which occurs in principle due to optical path length differences of the waveguide array 13 is suppressed with a particular wavelength region by providing a field distribution modulation element 16 in which a peak position of a field distribution continuously and periodically changes with respect to frequency at an incident side of the waveguide array 13.