| 摘要 |
PURPOSE:To obtain a large quenching rate and remove the necessity of consideration of insertion loss by making a demultiplexer to have a construction so that it separates and amplifies only a fixed wavelength by means of a semiconductor laser. CONSTITUTION:For instance, three wavelengths lambda1, lambda2 and lambda3 are made incident to an incident terminal 1. They are branched respectively by a branch circuit 5 and made incident to semiconductor lasers 6-8. The central wavelengths of gains of the lasers 6-8 are lambda1, lambda2 and lambda3, and three waves of lambda1-lambda3 are seperated by the lasers 6-8. In this case, the inrush current of lasers 6-8 is kept at a value less than threshold current Ith such as 0.99Ith. As a result, a large quenching rate is obtained and there is no need to consider insertion loss because only a specific wavelength can be separated and amplified. |
