| 摘要 |
<p>PURPOSE:To prevent the mutual interference between both emitted light signals by detecting the phase difference between the frequency divided signal of a first frequency dividing circuit and the frequency divided signal of a second frequency dividing circuit in a phase detector circuit, and feeding back a correcting signal corresponding to the phase difference into a first oscillating circuit. CONSTITUTION:The oscillating frequency of the transmitted signal from a first oscillating circuit OSC 1 is automatically adjusted to the oscillating frequency in a second oscillating circuit OSC 2. The phase of the transmitted signal form the OSC 1 agrees with the phase of the transmitted signal from the OSC 2. Therefore, the signal is applied into a synchronization detecting circuit 7 under the state wherein the amplified signal in an amplifier 4 is perfectly synchronized with the transmitted signal from the OSC 2. Since the manual adjustment of the oscillating frequency from the OSC 1 is not required in this way, the adjustment of the oscillating frequencies and the phases of the OSC 1 and the OSC 2 become easy and correct. Furthermore, when a noise N in the figure A is generated at the time other than a pulse generating period, the transmitted signal in the figure C becomes a low level all the time, and the circuit 7 does not detect the synchronization. Therefore, the generation of erroneous detected synchronization signal is prevented, and the erroneous operations in circuits in succeeding stages are prevented.</p> |
