Patent ID: 6547451
Filing Date: 2003-04-15
Classification: G02B

Abstract:
An optical communications module for use in an optical transfer system for bidirectionally transferring a light signal through an optical fiber, the optical communications module having a light signal transmission capability, wherein the optical communications module comprises:a semiconductor laser; an optical fiber coupled to a front facet of the semiconductor laser; a light splitting element for light which is emitted from the front facet of the semiconductor laser and propagated within the optical fiber, an output-monitoring photodiode for reserving a portion of the light which has been split by the light splitting element as monitoring light, and generating a photocurrent based on the monitoring light, the photocurrent being used for controlling optical output of the semiconductor laser; an optical fiber-embedding type optical circuit, the optical fiber-embedding type optical circuit comprising the optical fiber being embedded in an optical fiber-embedding substrate; a reception photodide mounted on an upper face of the optical fiber-embedding substrate; a metal total reflection film provided on an bottom face of the optical fiber-embedding substrate; wherein the light splitting element comprises a half mirror which is inserted in the optical fiber-embedding substrate at an angle with respect to a central axis of the optical fiber, the half mirror laying in an optical path within the optical fiber, wherein the output-monitoring photodiode is mounted on the upper face of the optical fiber-embedding substrate, and wherein an external light signal propagated through the optical fiber is reflected from the half mirror so as to be received by the reception photodiode, and the monitoring light is reflected by the half mirror and the metal total reflection film so as to be received by the output-monitoring photodiode, whereby the optical communications module has an optical signal transmission/reception capability.