EXTERNAL RESONATOR-TYPE LIGHT EMITTING DEVICE

摘要

An external resonator-type light emitting device comprising: a light source that oscillates a semiconductor laser light; and a grating element configuring this light source and an external resonator. The light source comprises an active layer that oscillates semiconductor laser light. The grating element comprises: an optical waveguide having an incident surface to which the semiconductor laser light is incident and an emission surface that emits an emission light of a desired wavelength; a Bragg grating formed inside the optical waveguide; and a propagation section provided between the incident surface and the Bragg grating. The relationships in formulas 1 to 4 are fulfilled.