Polaroid (polarizer) Polaroid (polarizer) Polaroid is a type of synthetic plastic sheet which is used as a polarizer or polarizing filter. A trademark of the Polaroid Corporation, the term has since entered common use. The original material, patented in 1929 and further developed in 1932 by Edwin H. Land, consists of many microscopic crystals of iodoquinine sulphate (herapathite) embedded in a transparent nitrocellulose polymer film. The needle-like crystals are aligned during manufacture of the film by stretching or by applying electric or magnetic fields. With the crystals aligned, the sheet is dichroic: it tends to absorb light which is polarized parallel to
Polaroid Corporation Originals" later in 2017. In the 1990s, Polaroid was involved in corporate sponsorship of NASCAR. For several years, Polaroid was the principal sponsor of NASCAR's 125 mile Featherlite Modified race at Watkins Glen and it was called the "Polaroid 125". The Polaroid name was also used in sponsorship in the NASCAR Busch Series. In 1992, Polaroid was the principal sponsor of female NASCAR driver Shawna Robinson's #25 Oldsmobile in the Busch Series. They continued as her principal sponsor when she moved to the other car numbers in 1993 and 1994. Polaroid formerly sponsored the Target Chip Ganassi entry of Juan