| 摘要 |
PURPOSE:To attain an optical fiber type pressure sensor which can have the diameter narrowed and is easy to produce by combining an optical elastic element and a polarization plane maintaining optical fiber. CONSTITUTION:The light from a light source 4 is made incident to a polarization plane maintaining optical fiber 6 through a beam splitter 9, a 1/2 wavelength plate 11, and a microlens 13. This light is propagated as linearly polarized waves in the fiber 6 and is made incident to an optical elastic element 7 through a microlens 14 and a 1/8 wavelength plate 12. The reflected light reflected on a reflective face 8 of the optical elastic element 7 is propagated to the 1/2 wavelength plate 11 in the opposite direction through the same path as the incident light. This reflected light is made incident to a photodetector 52 for measurement through a beam splitter 9 and a polarizing plate 10. When a pressure (p) is applied to the optical elastic element 7 in this constitution, the photo detection level of the photodetector 52 is changed in accordance with the pressure (p). Thus, the optical fiber type pressure sensor which can have the diameter narrowed and is easy to produce is attained. |
