ETHOCEL ethylcellulose polymers from Dow Chemical provide an alternative material to tri-acetyl cellulose (TAC) for LCD retardation films to increase viewing angle and contrast through its unique birefringence optics, excellent optical transparency, and low haze. Moreover, a new ETHOCEL-based polymer system has recently been developed with new optical properties such as tunable birefringence an...

Polarization decorrelation in single-mode fibers with randomly varying elliptical birefringence is studied. It is found that the effects of ellipticity on the polarization decorrelation length depend on the relative sizes of the beat length and the autocorrelation length of the birefringence fluctuations in the fiber. However, the evolution of the differential group delay remains unaffected by ...

We report an unusually large birefringence modulation in fiber-optic phase modulators formed with cylindrical piezoelectric transducers when driven at a few hundred kilohertz. The magnitude of the birefringence modulation is a strong function of modulation frequency. A simple model is used to explain the phenomenon, and the theoretical predictions agree well with the experimental results.

The spectral resolution is a main index of evaluating the performance of the designed acousto-optic tunable filter (AOTF). In this letter, an accurate expression of the spectral resolution is presented by considering both the birefringence and the rotatory property of TeO2 crystal. The deduced expression is significant in improving the accuracy of the design of an AOTF and pushing the developme...

Vacuum birefringence is governed by the amplitude for a photon to flip helicity or polarisation state in an external field. Here we calculate the flip and non-flip amplitudes in arbitrary plane wave backgrounds, along with the induced spacetime-dependent refractive indices of the vacuum. We compare the behaviour of the amplitudes in the low energy and high energy regimes, and analyse the impact...

In this work, an experimental approach of speckle photography was used for measuring birefringence of thermotropic liquid crystals mixtures at different wavelengths in the visible region. Also the dispersion relations were investigated. The values of the refractive indices were measured for these mixtures of thermotropic liquid crystals in isotropic and liquid crystal phase at different wavelen...

Purpose Glaucoma damages the retinal nerve fiber layer (RNFL). This study used precise multimodal image registration to investigate the changes of the RNFL reflectance spectrum and birefringence in nerve fiber bundles with different degrees of axonal damage. Methods The reflectance spectrum of individual nerve fiber bundles in normal rats and rats with experimental glaucoma was measured from ...

A particularly sensitive birefringence technique is used to analyze a curved DNA fragment with 118 bp and a standard DNA with 119 bp. At salt concentrations from 0.5 to 10 mM, both fragments show the usual negative stationary birefringence and monotonic transients - differences are relatively small. At 100 mM salt the curved DNA shows a positive stationary birefringence and non-monotonic transi...

The electro-optical effect of a magnetically biased ferronematic liquid-crystal film is investigated by using birefringence measurements. When a magnetic field is applied, the threshold voltage of the Freedericksz transition no longer exists. The dependence of the birefringence on the magnetic field strength in the low field regime is presented. A theory that accounts for the results is given.