Patent ID: 7442912

Claim:
An optical logic device for use in an optical communication system, which performs a logic operation on a plurality of input pulsed light signals having bit rates of 10 Gbps or more, comprising: a photoelectric conversion portion, in which photoreceivers for receiving the input pulsed light signals at bit rates of 10 Gbps or more are provided in parallel, that outputs a pulsed electric signal obtained by directly adding up pulsed outputs of the photoreceivers; and a comparator that compares a voltage level of the pulsed electric signal outputted from the photoelectric conversion portion with a predetermined voltage level wherein said photoreceivers comprise an anode and a cathode, and the anodes of said plurality of photoreceivers are electrically coupled together and the cathodes of said plurality of photoreceivers are electrically coupled together, whereby there is direct addition of the pulsed outputs of said photoreceivers.