MODULE FOR OPTICAL COMMUNICATION AND OPTICAL ISOLATOR TO BE USED FOR THE SAME

摘要

PROBLEM TO BE SOLVED: To prevent characteristics from getting unstable by the return of light reflected on the end face of a lens side optical element at an optical isolator to a light emitting element by inclining the light incident plane of this optical element larger than the angle of tapered light at least. SOLUTION: Emitted light 50 from a light emitting element 20 is converged by a lens 30 and becomes tapered light. The angleαof tapered light to a center line X connecting the light emitting element 20 and an optical fiber 40 is adjusted almost into 3 deg.-5 deg.. This tapered light is passed through an optical isolator 10 and converged just on the end face of the optical fiber 40. A light incident plane 11a of a polarizer 11 as the optical element closest to the lens 30 at the optical isolator 10 is inclined toward the plane vertical to the center line X connecting the light emitting element 20 and the optical fiber 40 and its angleβis made larger than the angleαof tapered light.