LIGHT MODULE FOR LIGHT AMPLIFIER

摘要

PURPOSE:To provide a compact, high-reliability light module by producing one united body with integrated light functions by partially vapor-depositing various open optical films such as wave dividing film, coupler film and polarization separating film on the surface of first and second parallel flat plateshaped glass substrates and by making optical path configuration for reflection or refraction on the surface and inside substrate of the glass substrates. CONSTITUTION:A light circuit in front of a rare earth dope optical fiber 10 and a light circuit on the rear of said optical fiber relative to the signal light propagation direction are arranged in a common cabinet 42. A coupler prism 58 on which the first coupler film 62 is formed at least on one of the surfaces 60a of the first parallel flat plate glass 60 and an exciting prism 64 on which a wave dividing film 68 is formed at least on one of the surfaces 66a of the second parallel flat plate glass 66 are arranged respectively with a predetermined angle of tilt relative to the optical path of signal light within the cabinet 42. And the first and second light-receiving elements 20 and 36 respectively receiving signal light at input side and signal light at output side reflected and branched by the coupler film 62 are attached to the cabinet 42.