Patent ID: 6282000
Filing Date: 2001-08-28
Classification: G02B

Abstract:
An optical transmitting and receiving module provided with a returning-light preventing means, comprising:a casing block;a light-emitting device for emitting a transmitting light beam, a first lens for collimating the transmitting light beam emitted from the light-emitting device, an optical demultiplexing filter for passing the light beam collimated by the first lens, and a second lens for collecting the light passing through the optical demultiplexing filter at an end face of an optical fiber, said light-emitting device, said first lens, and said second lens being coaxially disposed in said casing block;a third lens for collecting a receiving light beam emitted from the end face of the optical fiber, collimated by the second lens, and reflected from the optical demultiplexing filter, and a light-receiving device for receiving the light collected by the third lens, said third lens and said light-receiving device being disposed in said casing block; anda cover for covering a front space adjacent to a mounting surface on said casing block, said mounting surface being provided for mounting the optical demultiplexing filter on the casing block,wherein the cover is provided with the returning-light preventing means for preventing the transmitting light beam reflected from the optical demultiplexing filter from reaching the light-receiving device, said returning-light preventing means comprising a tongue piece formed by cutting and folding a part of the cover.