Patent ID: 7061669

Claim:
An optical apparatus having loss compensation capability, provided with an optical amplifier for compensating any loss generated in a loss medium, wherein said optical amplifier comprises: an optical amplification unit provided between an input terminal and an output terminal; an input side monitor unit for monitoring the power of the light transmitted from the input terminal to the optical amplification unit; an output side monitor unit for monitoring the power of the light transmitted from the optical amplification unit to the output terminal; and a gain control unit for controlling the gain in the optical amplification unit based on each monitor result of the input side monitor unit and the output side monitor unit, wherein said loss medium is connected to the optical path between the output end of the optical amplification unit and the input end of the output side monitor unit, and said loss medium is configured such that the amount of reflection attenuation on all points, on which the light is reflected on the optical path from the output end of the optical amplification unit to the output terminal, is smaller than the amount of reflection attenuation on an end face of the output terminal; and said gain control unit controls the operation of the optical amplification unit such that a gain at least equal to a loss generated in the loss medium is obtained.