| 摘要 |
PURPOSE:To modulate the quantity of light to be passed through optical fibers by sticking a total reflection preventing film on the fibers in the area along the axial direction thereof where there are not clads and controlling the elastic deformation rate of the part where said film is stuck. CONSTITUTION:The core 111 and clad 112 of an input optical fiber 11, and the core 121 and clad 122 of an output optical fiber 12 are formed continuously. The clad parts are stripped by a length L from these same optical fiber elements and a total reflection preventing material 18 formed of a material having a refractive index larger than the refractive index of the clad material is covered on the stripped parts thereof by coating. When the fiber 11 is fixed, and the angle theta of the fiber 12 is oscillated at theta=thetamSINomegat, the quantity of light to be passed therethrough can be changed periodically. As the refractive index of the total reflection preventing material is larger and the coating width is longer, the sharper pulsative light is obtained, but the absolute value in the quantity of light passed through the fiber is decreased. |
