LIGHT SIGNAL BRANCHING CIRCUIT WITH MONITOR

摘要

PURPOSE:To stabilize the mode distribution of light incident to the photo branching circuit and stabilize the quantity of branching by providing a mode distribution shaper for removing of undesired modes or shaping of mode distribution to the optical fibers connecting a light source and the photo branching circuit. CONSTITUTION:In the light signal branching circuit which connects a light source 301 and a photo branching circuit 303 having a monitoring terminal by means of optical fibers and outputs light signal to two or more output terminals of the photo branching circuit 303, a mode distribution shaper 302 intended for removing undesired modes or shaping mode distribution is provided between the optical fibers 304, 305 connecting the light source 301 and photo branching circuit 303, whereby the mode distribution of the light entering the photo branching circuit 303 may be stabilized, hence the quantity of branching of the photo branching circuit 303 may be stabilized.