A test of the qualities of polarizing filters was performed for a set of specimens including a bulk Nicol prism, standard polaroids, and special polyvinyl alcohol (PVA)-iodine thin-film filters coated on both sides by vertically oriented carbon nanotubes. The residual transmission of polarizing filters depending on the incidence angle of polarized light was examined in detail. The superior quality of polarizing film filters treated with carbon nanotubes was found. This fact allows us to propose a new application for polarizing films with carbon nanotubes for a polarizing cover glass. In such a way the cover glass may serve as an analyzer in a light polarizing microscope. Some features of optical scheme arrangement for the polarizing technique are discussed. The polarizing cover glass allows elimination of depolarization of light, which is inserted in a microscope objective. Test results of the proposed polarizing technique attest to the efficiency of using the polarizing cover glass. The new scheme for polaroid arrangement shows image-contrast enhancement by several percent in comparison with the standard layout.
Keywords: light microscopy; nanotubes; polarization technique; polarizing cover glass; polarizing film.