Junichi Hasegawa and Kazutaka Nara
There is an urgent need for an arrayed waveguide grating (AWG), the device that handles the function of wavelength multiplexer/demultiplexer, that is unaffected by temperature, i.e., athermal. To satisfy this requirement we have applied proprietary athermalizing technique, resulting in development of a multi-channel athermal AWG, which had not been achieved previously. Also, by design of the circuit pattern it has been possible to achieve a 100-GHz 48-channel athermal AWG module that has an insertion loss of less than 2.8 dB. For all channels, temperature dependence is less than ±0.015 nm for center wavelength and ±0.1 dB for insertion loss.