| 摘要 |
<p>PURPOSE:To achieve the measurement of a DC electric field by rotating a medium having an electrooptic effect provided to an electric field detecting section in an electric field measuring apparatus comprising a light source, an electric field detecting section and a photometry section. CONSTITUTION:Output of a light source 1 comprising a light emitting diode enters an optical fiber 2 and introduced into a detection section A, which is composed of a lens 3, a polarizer 4, an electrooptic crystal 5, a Wollaston prism 6 and lenses 3-1 and 3-2. Light separated into two beams of linear polarized light with a prism 6 is introduced to a measuring section B through optical fibers 3-1 and 3-2. The measuring section B computes detection outputs P1 and P2 of PIN photodiodes 9-1 and 9-2 with an arithmetic circuit 10 and outputs an AC output signal S to measure the intensity of an electric field. A crystal 5 is held with jigs 7-1 and 7-2 and turned on axis N2 gas blown through a plastic tube 8 from outside. Thus, the DC electric field shown by the arrow E can be detected as change in the signal S.</p> |
