| 摘要 |
PURPOSE:To improve the quality of a receiving signal by shortening a pulse width only for a constant time, and making smaller the change of the pulse width of the receiving signal for the transmitting signal, in an optical receiver which extends the received optical pulse train and makes it into the receiving signal. CONSTITUTION:The optical pulse train sent from the transmitting side through the optical fiber is detected by a photodetecting element 8, amplified 9, compared with a reference electric potential 11 at a comparing circuit 10 and reproduced as the pulse-shaped electric signal. Next, the pulse train is extended by an integrated circuit 12, inputted to the negative terminal of a comparator 13', compared with a reference voltage 14, the signal of the polarity inverted against the original signal is obtained, and through a resistance 16, a transistor (TR) 17 is driven. The collector of the TR17 comes to be an output terminal, outputs a low level in an on-condition and outputs a high level in an off- condition. When the TR17 comes to be from on to off, switching is delayed for the constant time by an accumulating effect. Thus, the pulse width of the receiving signal is made narrow to the transmitting signal to that extent, and the quality of the receiving signal is improved. |
