Optical path switching device

Abstract

With the invention, it is possible to suppress losses of light for monitoring and enhances the optical confinement efficiency into an optical fiber for output over the related art. The optical path switching device 20 includes: a platform 22 housed in an enclosure 21 and mounting various types of optical components; optical fiber collimators 23, 24 as optical input means; an optical fiber collimator 25 as optical output means; a parallelogram prism 26 for switching over the optical path between the optical fiber collimators 23, 24 and 25 based on a change in its position; and light receiving elements 31, 32 for detecting a portion of the light inputted from the optical fiber collimators 23, 24 in order to monitor the light; and controls the position of the parallelogram prism 26 in accordance with the monitoring result of the light. The light receiving elements 31, 32 are arranged to detect only a portion of the light in the outer part in radial direction.

Dependencies are inferred from the claim text.