| 摘要 |
PROBLEM TO BE SOLVED: To provide an optical branch circuit with which temperature dependence of a branched wavelength is eliminated. SOLUTION: This optical branch circuit consists of an optical circulator 102 that outputs a signal light received at a 1st port to a 2nd port as an input means and outputs a signal light received by the 2nd port to a 3rd port as an output means, plural temperature compensated fiber Bragg gratings 103, 104 that are provided for the 2nd port and whose reflecting wavelength bands differ from each other, a chirped fiber grating 106 that receives the signal light transmitted through plural fiber Bragg gratings are provided for the 2nd port, and a temperature compensated fiber Bragg grating 105 that receives the signal light transmitted through the chirped fiber grating and provided for the 2nd port, so that a temperature independence optical branch circuit is obtained. |
