| 摘要 |
PURPOSE:To always execute optical space transmission with high quality by using a laser diode of the single mode having any oscillation wavelength among preycribed wavelengths so as to avoid the adverse effect of an absorption spectrum. CONSTITUTION:The optical space transmission employing a laser beam is implemented between optical space transmitters 81, 82 and the laser beam generated by the transmitter 81 is emitted via a lens 83 and the transmitter 82 receives the laser beam from the transmitter 81 via a lens 84. Similarly the optical space transmission from the transmitter 82 to the transmitter 81 is implemented. The frequencies for transmission and reception differ from each other in the transmitters 81, 82. In this case, the laser diode in the single mode state having a stimulated wavelength among wavelengths of 770-810nm is employed. As a result, the probability of deteriorated S/N caused when the laser beam approaches an absorbed spectrum region is remarkably reduced. |
