| 摘要 |
PURPOSE:To provide a magneto-optical element using Faraday effect and a magnetic field measuring device using the element, which have stable characteristics against thermal change in particular around room temperature. CONSTITUTION:A magneto-optical element according to the invention consists of rare earth garnet crystal having a constant sensitivity against thermal change around room temperature, wherein the composition is expressed by Eq. I where X, Y, Z, and W shall range 0.8<=X<=1.3, 0.1<=Y<=0.3, 0.1<=Z<=1.0, and 0.3<=W<=0.8. This element constitutes a magnetic field measuring device together with a light source having the center wavelength in 0.8mum band. The thermal change in the sensitivity constant of this magneto-optical element is + or -4.0% in the temp. range from -50 deg.C to +100 deg.C. The magnetic field measuring device using this element achieves a thermal stability which does not present ant practical problem. |
