| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an optical receiver and an optical transmission system using the optical receiver for receiving an optical signal by stale reception characteristics by holding light reception current to be outputted from a light reception element of the optical receiver approximately constant. <P>SOLUTION: An optical preamplifier 1 which has an optical fiber for amplification and a laser light source for supplying an excited light to the optical fiber for amplification, and amplifies the optical signal is installed at the prestage of the optical receiver 3 having a photodiode 30 that detects the optical signal. In addition, an amplification control means 5 for controlling amplification gain of the optical signal in the preamplifier 1 is provided to the optical preamplifier 1 and the optical receiver 3. The amplification control means 5 controls power of the excited light to be supplied from the laser light source to the optical fiber for amplification in the optical preamplifier 1 according to the light reception current outputted from the photodiode 30 of the optical receiver 3. <P>COPYRIGHT: (C)2004,JPO |
