WAVEGUIDE TYPE OPTICAL DEVICE

摘要

In a waveguide type of optical device a waveguide layer for propagating light is provided on the front surface of a substrate. A compensation layer having a coefficient of thermal expansion substantially equal to that of the waveguide layer is formed on the rear surface of the substrate. The result is to reduce fluctuations of light propagation characteristics due to thermal stress; also to avoid warping or cracking of the substrate.