Wide-band light amplifier/receiver using double electrode type light amplifier

PURPOSE: To increase series resistance and junction resistance of a second amplifying part used for detecting an optical signal which is higher than that of a single electrode optical amplifier having an equivalent optical gain, and to increase the ratio of carrier wave versus noise and band width by using an optical amplifier, equipped with first and second current-injection electrodes. CONSTITUTION: A first current-injection electrode 140 has a length L 1 . An optical amplifier part arranged in the neighborhood of the electrode 140 has a gain G 1 . A second current-injection electrode 142 has a length L 2 . An optical amplifier part arranged in the neighborhood of an electrode 142 has a gain G 2 . A full length L of the amplifier is given as L 1 +L 2 , and a full gain G of the amplifier is given as G 1 +G 2 . A bias current source 144 supplies bias currents I 1 .I 2 through current-injection terminals 146 and 148 to the electrode 140 and 142. The current- injection terminal 148 is connected through a coupling capacitor 150 with a detecting circuit 152 which is a radio frequency or microwave receivign device or another arbitrary suitable circuit, which uses an optical signal to be detected appearing at the current-injection terminal 148. COPYRIGHT: (C)1993,JPO