| 摘要 |
PURPOSE:To obtain the amplifier, which can directly amplify a light singal without photoelectric transducing action, can implement the amplification action by using one common element with respect to multiplex wavelength signal light, and has a compact, simple constitution. CONSTITUTION:Two facing reflecting surfaces 3 and 4 are providing in a single current injecting type semiconductor laser amplifier element 1. Light is inputted to one side and outputted from to other side. The reflecting surfaces 3 and 4 act as a half mirror. When a forward direction current is injected from a terminal 2, the element 1 starts laser oscillation at a certain current value or more. Under the bias state lower than this oscillation limit, the Fabry-P erot resonating type linear optical amplifier having a gain vs. frequency characterisic shown by a solid line is obtained. In this amplifier, each carrier wavelength of the incident multiplex wavelength signal light (f1...fN in frequency indication) is set so that it agrees with the frequency of a resonating point. When the multiplex wavelength signal light, whose carrier frequency is the frequency f1... or fN which is equal to the resonance frequency of the amplifier, is inputted into the resonating type optical amplifier 1, respective light is directly amplified, transmitted through the other reflecting surface 4, and taken out. |
