| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a semiconductor laser device which can restrain an increase of light loss in a ring resonator and which can enlarge a free spectral range (FSR) of the ring resonator. <P>SOLUTION: A semiconductor laser element 1A comprises: a gain region 10a including a gain waveguide; a variable DBR region 10b where a diffraction grating is formed; a light reflection end surface 4b which faces the variable DBR region 10b with the gain region 10a in-between; first and second ring resonators 10d and 10f including respective circular waveguides and light couplers; a light waveguide 3 which extends along a predetermined axis direction of light with one end thereof optically coupled to the light reflection end surface 4b. The first and second ring resonators 10d and 10f are optically coupled to the light waveguide 3 through the respective light coupler. The variable DBR region 10b, the gain region 10a, and the light reflection end surface 4b together constitute a laser resonator. The FSR of the first ring resonator 10d is different from the FSR of the second ring resonator 10f. <P>COPYRIGHT: (C)2012,JPO&INPIT |
