| 摘要 |
PURPOSE:To efficiently utilize a light emitting element and to reproduce pulses without any error by using a differentiated signal as the driving signal for a light emitting element and obtaining pulses before differentiation by the use of a flip-flop circuit at the time of the reproduction. CONSTITUTION:A digital signal 11 is differentiated by a differentiating circuit 22 to obtain the differentiated signal. A separating circuit 23 which uses a diode, etc., divides the signal into a plus-directional differentiated signal 13 and a minusdirectional differentiated signal 14, which is inputted to a multiplexing circuit 28 through an inverting circuit 26 and a clamp circuit 27 which clamps the signal to 0V. The plus-directional differentiated signal 13 is clamped to 0V through a delay circuit 24 and a clamping circuit 25 and inputted to the multiplexing circuit 28. With the driving signal for the light emitting element 29, the light emitting element 29 emits light to a space and after the light is converted into an electric signal by a light receiving element 30, a flip-flop circuit 31 which changes in direction in response to each rising pulse can obtains the same reproduced signal 17 with the digital signal 11, thereby removing the influence of jitters generated by a transmission system. |
