| 摘要 |
PURPOSE:To allow the communication equipment to hardly receive a transmission fault in air by converting plural beams with different wavelength modulated by a transmission data into one beam by means of a prism, propagating the beam in air and allowing a reception side to separate the beam into plural different beams with different wavelength by means of a prism. CONSTITUTION:Three beams with different wavelength modulated by a transmission data is collimated into one beam with a prism PR1 and the beam radiates into space. The one beam is made incident a prism PR2 of a receiver R through space and the prism PR2 separates one incident beam into 3 collimated beams with different wavelength equal to the three beams before the incident in the prism PR1. One beam is propagated in space and the passing area is enough to be less, then the probability of receiving effect due to an obstacle such as smoke is reduced on the way of propagation. |
