Optical changing-over switch device

PURPOSE:To enable changing-over to be accomplished easily by forming a tapered surface having a perfect reflection surface to one end face of a single optical fiber and enabling the coupling from the ends of a plurality of optical fibers to be selected. CONSTITUTION:If a single optical fiber 5 is positioned in a solid line position and a surface 7 is abutted against the end of an optical fiber 3, the light of the single optical fiber 5 totally reflects on a tapered surface 6 and is entered into the optical fiber 3 by way of the surface 7 as shown by the arrow. On the other hand, if the signale optical fiber 5 is moved to the position shown by a dotted line, said light is entered to the optical fiber 1. In this way, the optical changing-over operations to the optical transmission lines of the optical fibers 1, 2, 3 are made easily by moving the single optical fiber 5. In addition, the light perfectly reflects on the tapered surface 6 and the losses of the light on the surface where both fibers are abutted are less.