| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a semiconductor laser device that is suitable for a forward- direction exciting light source of a Raman amplifier. <P>SOLUTION: The semiconductor laser device 100 is provided with an active layer 45 having a multiple quantum well structure and separation closing hetero structure (SCH) layers 42, 44, 50, and 52 that are formed above and under it. An intermediate layer 15 is adhered to an upper surface of the uppermost SCH layer 52. An upper clad layer 16 is adhered to the upper surface of the intermediate layer 15. A constant diffraction grating 36 is provided along the total length of the active layer 45 on a boundary between the intermediate layer 15 and the clad layer 16. The semiconductor laser device oscillates in multi mode, so that its output light hardly scatters in an optical fiber. Furthermore, the semiconductor laser device is lower in RIN and superior in wavelength stability. <P>COPYRIGHT: (C)2003,JPO</p> |
