| 摘要 |
PURPOSE:To improve the detection sensitivity, by branching a linearly polarized light to a transmitted light and a reflected light and allowing these lights to pass through a coil-shaped polarization plane preserving optical fiber and detecting the phase difference between both lights through a 1/4 wavelength plate. CONSTITUTION:The light from a laser light source 1 is linearly polarized completely by a polarizer 2 and has the direction adjusted optionally by a 1/2 wavelength plate 3 and is branched by a beam splitter 4. When the light is branched to the transmitted light and the reflected light by the beam splitter 4, one is incident to one intrinsic polarization axis from one end of a coil-shaped polarization plane preserving optical fiber 6 through a Farrady element 5, and the other is incident to said intrinsic polarization axis from the other end of said fiber 6 without passing the element 5. Lights propagated to the polarization plane preserving optical fiber are led to a 1/4 wavelength plate 7 by the beam splitter 4. |
