| 摘要 |
PURPOSE:To enable the omitting of evaporation processes of an insulating film and gold on a reflection terminal plane so as to facilitate mass production, by forming two branches of waveguides before at least one side in the resonance axis direction and terminating the two-branching waveguides respectively on specifically separated reflection terminal planes. CONSTITUTION:In a distributed feedback type laser device which performs an optical feedback operation by disposing a diffraction grating 14 in its inner part of waveguide structure, two branches 13b and 13b' of waveguides 13 are formed before at least one side in the resonance axis direction, and their two-branching waveguides 13a and 13a' are terminated respectively on separated reflection terminal planes 12 and 12'. A pair of the reflection terminal planes 12 and 12' are disposed on a position, where an optical wave propagated on one of said branching waveguides 13a and 13a' is reflected twice on the reflection terminal planes 12 and 12' respectively and then focused on the other one of said branching waveguides. Said distributed feedback type laser device, for example, is composed of a compound semiconductor as a main element, and a pair of said reflection terminal planes 12 and 12' are formed of crystal planes which are at an angle of 45 deg. to their cleavage planes and perpendicular to each other. |
