Patent ID: 6128423
Filing Date: 2000-10-03
Classification: G01R,G02B

Abstract:
A reflection type magneto-optic sensor comprising:a light path assembly having a light-inputting path and a light-outputting path parallel to each other;a lens having, a focal point, an optical axis parallel to the light-inputting path and the light-outputting path, and first and second surfaces normal to the optical axis;a polarizer;a bismuth-substituted rare earth iron garnet single crystal film; anda non-magnetic garnet substrate on which the bismuth-substituted rare earth iron garnet single crystal film is grown by a liquid epitaxial method; anda mirror;wherein the light path assembly, lens, polarizer, bismuth-substituted rare earth iron garnet single crystal film, non-magnetic garnet substrate, and mirror are aligned in this order along the optical axis;said light-inputting path and said light outputting path are disposed in proximity to the focal point so that light exiting said light inputting path enters said lens and is then reflected back by the mirror into said light-outputting path;said polarizer and said non-magnetic garnet substrate are shaped to taper in parallel and opposite directions so that the bismuth-substituted rare earth iron garnet single crystal film is sandwiched between the polarizer and the non-magnetic garnet substrate and inclined at an angle in the range from 3 to 20.degree. with a plane normal to the optical axis.