| 摘要 |
PROBLEM TO BE SOLVED: To provide a semiconductor laser element and an optical semiconductor device capable of achieving both improvement in frequency characteristics and improvement in manufacturing yield.SOLUTION: A semiconductor laser element comprises: a diffraction grating in which a first diffraction grating region of a first pitch, a second diffraction grating region of a second pitch, and a third diffraction grating region of the first pitch are aligned in contact sequentially from a light emission side; a reflection suppression film formed on an end surface at the light emission side; and a reflection film formed on an end surface at an opposite side to the light emission side. The first diffraction grating region is longer than the third diffraction grating region, and a phase of the first and third diffraction grating regions is shifted in a range from 0.6 &pgr; to 0.9 &pgr;. The second diffraction grating region has the second pitch and a length of the second diffraction grating region so that a phase is continuous at a boundary between the first and second diffraction grating regions and a phase is continuous at a boundary between the second and third diffraction grating regions. |
