Measurement of field-induced orientation of molecular aggregates is carried out simultaneously with measurements of dichroism and bi-refringence, using pulsed, polarized laser beams

摘要

Outputs from two or more modulated lasers (2, 3) are polarized differently. An optical system directs the beams through a sample (4) to a focal point. Light sensors detect signals from the lasers individually, each detecting a corresponding modulation. The signals are fed to an evaluation unit. An Independent claim is included for corresponding equipment to carry out the process. Preferred features: The evaluation unit determines double refraction , intensity, orientation and dichroism. The sample is preferably completely transparent, or translucent. Sample concentration is adjusted by applied pressure. The laser is pulse-modulated. It is fired in rapid succession, or the wavelength (color) is varied correspondingly. The modulation employed, is used in synchronizing measurements. The laser light is pulsed at a frequency between 102 Hz and 1010 Hz. Photodiode detectors (7) are employed. Laser polarizations are at differing angles; the lasers are laser diodes. Detected values are translated into mean values, by the evaluation unit. Evaluation is made from a succession of modulation states. A set of equations provided, is used to make the determinations cited above, with inputs of laser intensity, wavelength, and optical element orientations. A feature noted in the apparatus, is the semi-silvered mirror located at the intersection of the laser beams.