Semiconductor laser controlled by external cavity.

摘要

P One end of a semiconductor laser (1) is coated with an antireflection film (1A). An external resonator is constructed with a diffraction grating (2) and an external reflection mirror (4). In addition, a beam splitter (3) is provided between the diffraction grating (2) and the external reflection mirror (4). An output light from the laser is transformed into a parallel light (13A) and supplied to the beam splitter (3). The parallel light (13A) changes its light path at the beam splitter (3), and is then supplied to the external resonator. BR/ The beam splitter (3) is an external reflector on the side of the antireflection film (1A) and said external resonator transforms its resonance characteristic into a reflective characteristic by said beam splitter (3). / P