| 摘要 |
PURPOSE:To enable setting of the light-sensing face of a photodetector in an arbitrary shape by a method wherein a light to be measured which enters from the lateral side of an optical fiber is taken in as a core transmission light or is guided inside a core as an excitation light and taken in as a propagation light. CONSTITUTION:A photodetector 2, a waveform storage device 3 and a computer 4 are connected sequentially to one end of an optical fiber 1. A signal light enters from an arbitrary side of the fiber 1 and is propagated through a core part thereof, and the power of the light is detected by the photodetector 2. The optical fiber 1 has a clad 6 and a coating layer 7 provided outside a core 5, and for the layer 7, a material being transparent in the wavelength region of the signal light is used. The outer peripheral part of the clad 6 is formed of a scattering layer 8. The layer 8 may be provided also inside the layer 7. Accordingly, the signal light is transmitted as an incident light through the layer 7 and scattered in the layer 8 and part of it is taken in the core 5 and transmitted as a propagation light through the core and reaches the detector 2. As to a method of taking a transmission light in the core 5, the fluorescence of the signal light may be utilized as well. |
