PHOTODETECTOR AND OPTICAL DEMULTIPLEXER USING IT

摘要

PROBLEM TO BE SOLVED: To solve the problem that, when a light receiving element array 11 is mounted in a photodetector 1 inside a package 13 having a limited size, the package 13 becomes an obstacle even when an optical fiber and the array 11 are arranged so as to become an ideal Littrow arrangement, and that the optical fiber and the photodetector 1 cannot be arranged adjacent closer than a certain distance. SOLUTION: The photodetector 1 is provided with the light receiving element array 11, the package 13 on which the array 11 is mounted and a transmissive window 13 through which light to be detected is made incident on the light receiving face of the array 11. An opening 14 which can transmit a beam of light parallel with the light to be detected is formed in a position adjacent of the array 11 in the package 13.