| 摘要 |
<p>PURPOSE:To manage with one optical fiber, and to reduce the size and improve the operativity by providing a sensor part atop of the optical fiber and returning light to a photodetection part through a reflecting mirror. CONSTITUTION:Light from a light source 1 is incident on the optical fiber 8 through a coupler 6a, half-mirror 7, and coupler 6b, and then incident on a polarization beam splitter 9 through a coupler 6c, so that linear polarized light passes through a Pockels element 3 applied with an electric field E. This transmitted light is passed through a 1/8-wavelength plate 10, reflected by the reflecting mirror 11 and passes through the wavelength plate 10 again, and further transmitted through the splitter 9. Then, the light returns to the optical fiber 8 and is incident on and detected by a photodetecting element 12 through the coupler 6b, mirror 7, and coupler 6b. Then, the light is amplified by an amplifier 13 and separated by a filter 14 into the AC and DC components; and a divider 15 outputs a signal proportional to the applied electric field E, thereby measuring the applied electric field E.</p> |
