PHOTODETECTING MODULE AND WAVELENGTH MULTIPLEXING SIGNAL TRANSMISSION AND RECEPTION MODULE USING THIS MODULE

摘要

PURPOSE:To obtain the photodetecting module which is small in size and has high coupling efficiency by polishing the front end of an optical fiber to 45 deg., providing a 1st interference film filter to the front end thereof, changing the progressing direction of the light propagated in the optical fiber and making the light incident on a photodetector via a 2nd interference film. CONSTITUTION:The photodetecting module part of the photodetector 2 is constituted by having a piece of the optical fiber 4 which is polished to 45 deg. at the front end, a supporting member 1 which is used to support and fix the optical fiber 4, the 1st interference film filter 17 which presses the 1st interference film 16 to the diagonally polished front end of the optical fiber, and the 2nd interference film 18 which is interposed in the route for directing the light reflected by the 1st interference film 16 of the 1st interference film filter 17 toward the photodetector 2. The light propagated in the optical fiber 4 is reflected by the 1st interference film 16 of the 1st interference film filter 17 provided in the part polished to 45 deg. and is made incident on the photodetector 2 provided near the optical fiber 4 via the 2nd interference film 18. The photodetecting module which is small in size and has the high coupling efficiency is obtd. in this way.