PURPOSE: To achieve the improvement of S/N and the improvement of frequency characteristics simultaneously by feeding the signal voltage appearing at the load terminal of a photo diode converting the light signal received to electric signal in in- phase back to another terminal of the diode.
CONSTITUTION: The input part of an amplifier 13 is connected to the load terminal 12 of a photo diode (PD) 11 which receives the photo signal P and from its output part, the light-electricity conversion output V0 is obtained. The electric signal from the output part of the amplifier 13 is fed back to the power source side terminal 14 or the PD 11 and therefore if the same signal is applied alternately between both terminals of the PD 11, the impedance of the PD 11 becomes extremely large and the PD 11 may be regarded as an ideal current source, thus it turns out that the capacity of the PD is virtually negligible.
| WO/2008/078819 | OPTICAL ACCESS NETWORK, REMOTE DEVICE, OPTICAL COMMUNICATION METHOD, AND OPTICAL COMMUNICATION PROGRAM |
| JP2002023118 | OPTICAL CIRCUIT |
| JP2000252925 | OPTICAL TRANSMISSION APPARATUS |
HANANO NAOMASA
IGUCHI KAZUO
| JPS4921049A | 1974-02-25 |
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