Voltage and electric field measuring device using light.

摘要

A voltage and electric field measuring device using light, including a polariser (2), an electro-optic crystal (4) consisting of a material having an optical rotatory power, and an analyser (5) arranged in this order in the direction of advance of applied light. A quarter-wave plate (3) is disposed between the polariser (2) and crystal (4) or between the crystal (4) and analyser (5). The angle of orientation Ψ of the analyser (5), relative to the optical axis of the crystal (4), is set to the product of 0 and f, where θ represents the optical rotatory power, with respect to the applied light, of the crystal (4) near a point at the centre of a range of varying temperatures at the installation environment, and e represents the thickness of the crystal (4) measured in the direction of advance of light. The specified relation between Ψ and θ·ℓ maximises the temperature stability of the device by ensuring that the sensitivity of the device is substantially independent of temperature.