| 摘要 |
<p>PROBLEM TO BE SOLVED: To detect a highly sensitive electric field by leading an incident light beam onto the upper surface of an electro-optic crystal which changes its refractive index depending upon an electric field so that the light beam incident upon the crystal is totally reflected at a boundary surface at its lower surface in order to return the incident light in the incident direction. SOLUTION: The upper and lower surfaces of an electro-optic crystal 41 made of ZnTe are optically polished, and the upper surface of the crystal 41 is bonded to a prism 42 made of, for example, BK7. An incident light beam 41 is reflected upon a boundary surface between the lower surface of the crystal 41 and the air, having an incident angle of about 20deg. if the refractive index of the crystal 41 is 2.9. The prism 42 has an inverted trapezoidal shape so that a light beam from thereabove is incident upon the crystal 41 and the beam reflected at the lower surface of the crystal is returned upward. With this arrangement, an electric field having a high intensity is applied only to the boundary surface in order to measure an electric field intensity of the boundary surface of the crystal 41, thereby it is possible to enhance the detecting sensitivity.</p> |
