Patent ID: 8885675
Filing Date: 2014-11-11
Classification: H01S

Abstract:
1. A wavelength variable laser device, comprising: an optical filter formed by three ring resonators having different optical path lengths from each other, wherein the ring resonators are formed by optical waveguides that are formed in a planar lightwave circuit; a semiconductor optical amplifier being of a Fabry-Perot type that supplies light supplies light to the optical filter, the semiconductor optical amplifier including: a single active layer that is formed entirely with a same composition, and a phase-modulation electrode that performs high-speed phase modulation for suppressing stimulated Brillouin scattering of output light by changing a refractive index of the active layer through implanting electric current to the active layer; a light reflecting section that returns the light transmitted through the optical filter to the semiconductor optical amplifier via the optical filter; optical waveguides which are formed in the planar lightwave circuit and connect the semiconductor optical amplifier, the optical filter, and the light reflecting section; a wavelength variable section comprising three film-like heaters that change a wavelength of the light transmitting through the optical filter by separately changing temperatures of the optical waveguides that constitute the three ring resonators; a phase variable section comprising a film-like heater that performs a phase adjustment for optimizing a phase of a laser resonance of the light propagated on the optical waveguides by changing temperatures of one of the optical waveguides connecting the semiconductor optical amplifier, the optical filter, and the reflective section or temperature of one of the optical waveguides connecting the plurality of ring resonators; a light-receiving element that detects light from at least one of the plurality of ring resonators via a through-port; and