Polaroid

Polaroid is the name of a plastic type of sheet in synthetic which is employed for to polarize the Lumière. It is a Registered trademark of Polaroid Corporation.

The original material, patented in 1929 and improved in 1932 by Edwin H. Land, is composed of many microscopic crystals of Sulfate of iodo Quinine (Herapathite) built-in a transparent film of Polymère of Nitrocellulose. The crystals Aciculaire S are aligned during the manufacture of film by drawing or by applying electric fields or magnetic. The crystals being aligned, the sheet is Dichroïque: it tends to absorb the light which is parallel to polarized the direction of the alignment of the crystals, but transmits the light which is polarized perpendicular to it. This makes it possible this matter to be employed like Polariseur of light.

This material, known under the name of sheet J , was replaced by the sheet H , improvement invented by Land in 1938. The sheet H is a polymer of the polyvinyl Alcool (PVA) soaked with Iode. During manufacture, the polymer chains of PVA are stretched so that they form a line of molecules aligned and linear in material. Iodine doping sticks to the molecules of PVA and makes them conducting over the length of the chains. The parallel to polarized light the chains is absorbed while the perpendicularly polarized light is transmitted.

The Polaroid sheets are used in screens with liquid crystals, Microscope S optics, stereoscopic Lunettes, and even, with an orientation different from the filters, Sunglasses which have the property to bar the light coming from the top, just like the reflections coming from bottoms, asphalt roads or water level.

The mark Polaroid is also used as commercial name for a variety of market products by Polaroid Corporation, of which camera and film and sunglasses based on the Polaroid polarizers with instantaneous impression.

The Polaroid gave its name to the artistic current Photographisme Polaroid.

See too

Articles on Wikipédia

External bond

  • Official site
  • French-speaking Patent
  • Forum of impassioned Polaroid

Random links:Larger than the love | Valicha | Vanessa gonerilla | Kiawak Ashoona | Guadalope | Liste_de_personnes_de_Tamil_Nadu