| 摘要 |
PURPOSE:To execute a digital transmission from a direct current up to a high frequency by means of a single module by dividing a light-receiving signal obtained from one light-receiving element into a high band component and a low band component, binarizing them for each frequency component, and thereafter, executing an addition (OR operation) again. CONSTITUTION:An amplifier 5 amplifies a light-receiving output signal by a light-receiving element 4, and a capacitor 7 causes only an alternating current signal component in the output of the amplifier 5 to pass. A comparator 9 compares the alternating signal component (voltage) to pass the capacitor 7 and a fixed reference voltage from a fixed reference voltage generating circuit 8, the comparator 9 outputs a digital signal, a comparator 11 compares an output signal (voltage) from the amplifier 5 and a variable reference voltage from a variable reference voltage generating circuit 10, and the comparator 11, outputs the digital signal. An OR circuit 12 executes the OR of the digital outputs of the comparator 9 and comparator 11, and the result is outputted to an output terminal B. Thus, an optical signal transmission from the direct current up to the high frequency can be executed by means of a single module. |
