| 摘要 |
PURPOSE:To extract many divided pieces of projection luminous flux, by making light incidence in one direction upon an optical deflecting element fixed in a housing through an optical fiber, and connecting optical fibers to projection ends of resulted zero-order diffracted luminous flux and plural pieces of diffracted projection luminous flux. CONSTITUTION:An optical demultiplexer is contained in a housing 11 which is fixing the optical deflection system consisting of an optical deflecting medium 7 made of tellurium dioxide or lead molybdate, transducer 8, and absorber 9. A signal processor 10 which drives the transducer 8 is modulated by an input signal (a) to output a high-frequency pulse signal (b). Incident light from a trunk optical fiber 12, on the other hand, strikes the optical deflecting medium 7 at an angle theta of incidence different slightly from the Bragg angle. For this purpose, the incident light is shifted within a range of + or -0.5-1 deg. from the Bragg angle and passed through a concave lens 13 and a reflecting mirror 14 to enter optical fibers 15-19 respectively, obtaining 5-7 pieces of diffracted projection luminous flux. |
