Polarization Optics, Polarimeters and Polarization Spectrometers

Abstract

Polarimeters, employing polarization optics, are well known as highly precise and accurate instruments for determining optically active substances. Even simple manual polarimeters offer high accuracies compared to other analytical methods. Also, more sophisticated devices with half‐shadow adjustment and with quartz‐wedge compensation were already constructed in early times of polarimetry. High improvement of polarimeters has been obtained with modern automated and semiautomated instruments. Until now, polarimetry has been the main analytical standard method for determining sucrose in the sugar and beverage industries and is an important tool for controlling production processes of optically active substances. For obtaining high precision and accuracy, the brightness and monochromaticity of the light source is important. While polarimetry is based on intrinsic optical activity, polarization spectroscopy also measures anisotropies that may be induced into isotropic atomic or molecular species by DC electric or magnetic fields or also by interaction with radiation. Doppler‐free methods of nonlinear polarization spectroscopy yield high spectral resolution and result in the suppression of interferences by extremely close‐lying lines. Polarization spectroscopy based on an applied DC magnetic field, which is also denoted as coherent forward scattering spectroscopy (CFS), allows simultaneous multielement determination in combination with continuum light sources and the measurement over an extremely wide dynamic range.

Desenvolvimento de um protótipo para medição de filtros polarizadores de óculos de sol de acordo com a NBR15111

“…Os polarizadores artificiais são construídos utilizando um dos seguintes efeitos: dicroísmo, birrefringência ou reflexão (HERMANN, 2007). A maioria dos polarizadores vendidos utiliza do dicroísmo, que é a anisotropia da absorção de luz, onde o coeficiente de absorção de luz é diferente para cada tipo de polarização (IIZUKA, 2002).…”