| 摘要 |
PURPOSE:To detect the production of a bit error in all circuits including the lighting means by decoding an output electric signal of a photodiode monitoring a back face light of a laser diode, and utilizing it for the detection of a bit error. CONSTITUTION:An input signal is code-converted by a coding circuit 2 and outputted to an optical transmitter 3. The optical transmitter 3 monitors the back light of the output light of the laser diode 5 by means of a photodiode 6 and the optical output is made stable at an APC circuit 4 by using a monitor waveform amplitude. The monitor waveform output of the photodiode 6 is supplied an identification device 7, from which the identified and subject to photoelectric conversion is outputted from the optical transmitter 3. The electric signal is decoded by a decoding circuit 9 and outputted to a bit error detection circuit 10. The bit error detection circuit 10 synchronizes the output signal of the decoding circuit 9 with the input signal 1 to apply error detection by bit by bit collation. |
