Real Time Measurement of Induced Variation of Birefringence in Transparent Media

Abstract

An apparatus permitting high accuracy measurements of fast variation of birefringence in various media has been built using the following principle. A feedback loop cancels automatically the corresponding rotation of the light polarization vector by a calibrated voltage change applied to a KDP crystal. It has been used to measure the optical damage effect in electro-optic crystals such as LiNbO3.

Fast and Simultaneous Measurement of Both Birefringence and Azimuth Angle Using a y-Cut LiNbO3 Phase Modulator

“…Several techniques have been reported for real-time measurement of birefringence for different purposes. These techniques can be sorted into three types: one is using left and right and circularly polarized laser beams with different frequencies, 1) which are generated by an axial Zeeman laser; the second is using photoelasticeffect modulator (PEM) 2) or electro-optic (EO) effect modulator 3,4) to produce the desired polarization-state modulation; the last is using four photo detectors. 5) Since the first method is limited to the Zeeman laser, it is unavailable for measurement of birefringent sample at different wavelength.…”

A Consideration of the Deformation of Rectangular Pattern

“…The optical birefringence can be observed by various methods. Light modulation methods (Primak andKampwirth 1971, Micheron andBismuth 1972) have recently been applied to detect variations of birefringence under external perturbations such as temperature, mechanical stress or electric field. Observation of the phase transition based on the measurement of An has been suggested by W C Walker (1974, private communication), who utilized a photoelastic modulator with a He-Ne laser to measure An down to Our method is analogous to Walker's method.…”