| 摘要 |
PURPOSE:To embody a small-sized, stable and highly efficient shorter-wavelength light source required for high-density recording of an optical disc, picture processing, etc., and a low-noise and stable light source demanded for measurement. CONSTITUTION:In a constitution composed of a semiconductor laser 601. collimating lens 602 and diffraction grating 603, the longitudinal mode of the semiconductor laser is brought to a multiple state when the collimating lens is placed in a defocused state, and stable green or blue shorter wave length laser light is made possible when the laser light is the excited light of a solid-state laser or polarization and inversion waveguide element. Also, the same effect can be realized when the period of the diffraction grating is divided or chirped. |
