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In optical systems for information processing based on spatial light modulators, the polarization components are widely used. Those components should provide a homogeneous polarization state over all their aperture. At the same time, numerous studies have revealed that there exists a large spatial scattering of the parameters of these elements. Determination of the quality of polarizers with the aid of polarimeter is known to be one of the most acceptable methods. One of the possible ways for solving this problem is just suggested here. Its advantage is that imperfections of polarizers which ensure creation and analysis of polarized light do not influence the values of parameters for testing polarizers.© (1997) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

Using the high-accuracy principles, spontaneous and induced parametric phenomena are studied in lead germanate-silicate Pb5(Ge1-xSix)3O11 (x equals 0.4) crystals near the ferroelectric phase transition. The symmetry of the phasers is appropriate for simultaneous measuring all the effects. It is essential that at re- polarizing crystals under the electric field, the optical activity sign changes, while the linear birefringence remains unaltered. This enables to find easily the parameters related to the systematic polarimetric errors. Although the crystals mentioned may be regarded as typical ferroelectrics with the second order phase transition, the temperature and the field dependencies of the effects measured depends notably on the sample conductivity, the domain structure and the light scattering at structural defects.© (1997) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

In most of modern polarimeters and ellipsometers a compensator is present which is used to change the ellipticity of light incident at a crystal in the PCSA system or compensate the ellipticity of light emergent from a crystal in the PSCA system. Most often, a quarter wave plate is used as a compensator. A problem of using the quarter wave plates of which fast axis has to be replaced by the slow one often arises in polarimetric experiments. For this aim the authors study the quarter wave plates made of Gd2(MoO4)3, and DKDP which allow to carry out the mentioned procedure by applying the external electric field to those crystals. In this work the possibility is analyzed for utilizing the compensator of this type in polarimetric investigations with elliptic polarizer. Use of electrically switched compensators in the polarizer-sample- compensator-analyzer system enables to analyze experimentally the 'HAUP maps' dynamics, when changing the output analyzer ellipticity, and evaluate the correspondence of the adopted mathematical model for the polarization scheme concerning the parasitic ellipticities p and q of polarizers.© (1997) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.