| 摘要 |
PURPOSE: To reduce the production cost by transmitting radiant light between two device units directly or through reflection, dispersion, or refraction and providing each device unit with a single frequency oscillator for transmission and reception. CONSTITUTION: The oscillation of an oscillator 4 modulates the power of an optical transmitter 12 through a current source 11 to perform transmission. Radiant light is received by an optical receiver 1 of the other device unit. Two device units are different by a selected average frequency of the frequency oscillator 4. A band filter 2 limits a signal within its spectrum, and its frequency is mixed with the corresponding local frequency of the frequency oscillator 4 in a mixer 3, and the sum of frequencies generated from the reception frequency is given to a frequency demodulator 6. Another band filter 7 is prepared following the frequency demodulator 6, and a frequency modulator 8 generates an electric signal of transmission/reception functions. The reception function is obtained by subtracting the transmission function from the signal of the frequency modulator 8 by a subtractor 9. |
