| 摘要 |
PURPOSE:To oscillate in a phase synchronous state by so forming light emitting regions that the arranging pitch of the diffraction gratings of the regions are different as to correct the displacement of the oscillation wavelength of the regions generated due to the difference of temperatures at the time of oscillation. CONSTITUTION:The arranging pitch of diffraction gratings 30 is so set, for example, that the light emitting region of the center is shortest and the pitches are gradually increased toward the periphery. To this end, the part except a semiconductor laser of a center on a substrate coated with resist is shielded, only the center is exposed, the exposure of the periphery is sequentially repeated similarly while altering the pitch of interference fringes, developed and etched to form a diffraction grating. Thereafter, third growth is conducted, and a semiconductor laser device is manufactured in the same steps as those in a conventional one. The arranging pitch of the gratings is shortened in a light emitting region in which temperature relatively becomes high, and the arranging pitch of the gratings is lengthened in the light emitting region in which temperature relatively becomes low, thereby correcting the displacement of the oscillation wavelength of each region. |
