JPS5555595A - Semiconductor light amplifier - Google Patents

Abstract

PURPOSE:To totally reflect or partially reflect light incident on an active totally waveguide path in zigzag manner on the end surfaces thereof to amplify the same, and to drive the thus amplified light by a current pulse synchronizing with the light pulse line of input signal thereby to amplify and shape the light pulse line of the input signal having a widened pulse width. CONSTITUTION:Reflection preventive films 24 made of Al2O3, SiO, CaWO4 and the like are evaporated on parts at the end surfaces on which input light 6 is injected and parts at the end surfaces from which output light 7 is emitted. At the end surfaces on which light is reflected, evaporated are dielectric films made of SiO, Al2O3 and the like in a certain length, and thereon provided is a reflection film 18 made of a metal such as copper, silver or the like. Light 6 propagated in the active layer at an angle of deflection theta', and advances in the width of a light waveguide path 51. Light 71 which has partially permeated is converted into an electric signal 73 by a photodetector 72 and a timing component 75 is extracted in a timing extraction circuit 74, and a driving current pulse 77 is produced in a pulse generator 76 on the basis of the component 75, the thus produced driving current pulse is applied to a lead wire 16. Thereafter, light amplified by the waveguide 51 is picked up as a light 7.