| 摘要 |
PURPOSE:To improve the accuracy of detection by polarizing light having single wavelength to transmitted light and reflected light, composing these polarized light by a polarized beam splitter through an optical fiber loop and converting the composite light into circularly polarized light to detect the light intensity of an interference wave. CONSTITUTION:Light rays having single wavelength projected from a light emitting element 1 are divided into two straight polarized light of which polarized surfaces are intersected at right angles each other by the polarized beam splitter 2. The reflected light is made incident to a terminal B of the optical fiber loop 5 through a coupled lens 4, transmitted into the optical fiber loop 5 as counterclockwise (CCW) light, projected from a terminal A as a horizontally polarized wave, and passed through an electrooptical element 7 as a horizontally polarized light through a lens 3. The transmitted light passes the electrooptical element 7 from left to right as vertically and straightly polarized wave. Clockwise (CW) light and the CCW light are composed after passing through the polarized light beam splitter 2 and converted into a circularly polarized wave through a lambda/4 plate 10 to detect the intensity of interference light by a photodetector 6. |
