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
Land Camera to expose, develop, and fix the photo into a plastic envelope commonly associated with a Polaroid photo. The Polaroid SX-70 camera was the first to utilize this film. Improvements in SX-70 film led to the higher speed 600 series film, then to different formats such as 500 series (captiva), and spectra. The original cameras folded into the body and used bellows to protect the light path. The film was put on two spools, one with the negative roll, and one with the positive paper and reagent pods. The film developed inside the camera. The exception to this is the Polaroid