| 摘要 |
PURPOSE:To branch the light with an equal branching ratio and without receiving a limitation of the number of branches, by using plural branching devices of a face- centered monoclinic shape containing an evaporated dielectric thin film. CONSTITUTION:The dielectric multilayer film 2 is formed on the single side of the quartz-made light branching device 4 having a face-centered monocline shape that is formed by three pairs of planes parallel to each other plus a pair of inclined planes 40 and 41 crossing other two pairs of inclined planes at 90 and 45 each. Then a serial adhesion is given among plural numbers of such devices 4 (for instance N units) via the resin having an equal refractive index as the quartz glass. In this case, a light reflection factor of 1/[N-(K-1)] and 1<=K<=N-1 is secured for the K-th dielectric multilayer film 2. As a result, the incident light P1 sent from the optical fiber 10-1 is branched into the lights P2, P3-PN+1 showing an intensity of 1/N to the intensity of the incident light to be put into each of the optical fibers 10-2, 10-3-10-(N+1). |
