| 摘要 |
PURPOSE:To restrain instability of laser oscillation within the bandwidth for transmitting a signal by setting the driving characteristics such that the oscillation wavelength is shifted more than the spectral width of each longitudinal mode occurring in a semiconductor laser before an emitted light is reflected back to the semiconductor laser. CONSTITUTION:A semiconductor laser 11 wavelength tube characteristics large enough to shift the wavelength of laser oscillation more than the spectral width of each longitudinal mode occurring in the semiconductor laser 11 before a light 12 emitted therefrom is reflected 16 back to the semiconductor laser 11. Since the wavelength is shifted within the semiconductor laser 11 itself, the probability of matching the wavelength of reflected light 16 with laser oscillation mode can be lowered significantly and the interference has no effect on the laser oscillation process to cause instability in the laser oscillation. This constitution allows errorless optical transmission. |
