| 摘要 |
PURPOSE:To extract single wavelength laser beams with excellent directivity in the vertical direction to a P-N junction surface while inhibiting an unnecessary mode resulting from reflection by burying a light-emitting region and simplifying a lateral mode and reducing driving currents while confining beams changed into a uniaxial mode in a ring shape by using a diffraction grating. CONSTITUTION:A striped region 14 consisting of an InGaAsP active layer 2, a P-InGaAsP guide layer 3, a diffraction grating 4, a P-InP clad layer 5 and a P- InGaAsP contact layer 6 is formed on an N-InP substrate 1 to a ring shape with mutually parallel two straight line sections. The striped region 14 is buried by a P-InP optical confinement layer 7 and an N-InP current stopping layer 8. A projecting section 13, which is shaped along the direction of the striped region 14 and a section thereof takes an arcuate form, is formed to a section corresponding to one of both straight line sections of the surface on the electrode 9 side of the substrate 1. The semiconductor laser device avoids a utilization for an optical resonator of a section where a semiconductor crystal is directly in contact with the outside air such as a cleavage plane, utilizes periodic index distribution shaped in a liquid crystal for the feedback of beams, and reduces reflection resulting from a large refractive index difference. |
