TWO-BEAM INTERFEROMETER FOR MEASURING OF REFRACTIVE INDEX OF ISOTROPIC AND ANISOTROPIC MATERIALS Russian patent published in 1998 - IPC

FIELD: measurement technology. SUBSTANCE: two-beam interferometer has laser light source 1 and semitransparent mirror 2. Plane of light incidence on mirror for exclusion of depolarization of radiation of laser 1 is parallel or perpendicular to laser radiation polarization plane. Interferometer is also provided with optical modulator 3 optical axis of which is at angle of 45 deg. to laser radiation polarization plane, polarizer 4 cross-positioned or parallel to laser radiation polarization plane. After passing through polarizer, beam gets on specimen 5 under test made as plane-parallel plate manufactured of material being tested. Interferometer has also two reflecting mirrors 7, 8 positioned at its output, photomultiplier 9 with slit at input, narrow-band amplifier 10, and recorder 11. EFFECT: higher accuracy of measurement. 2 dwg