Polaroid polarizing sheet
Lámina polarizadora Polaroid
- Date
- 1929-1933 · confidence high
- Place
- Cambridge, Massachusetts, United States
- Credited to
- Edwin Land
- Field
- Communication
What it is
A plastic film with aligned microscopic herapathite crystals that polarizes light, cheap and large in area, unlike natural crystals. It enabled polarized sunglasses, filters and displays.
Land started with herapathite (found by Herapath in 1852) and later used polyvinyl-alcohol sheets with iodine (H-sheet, 1938).
What it led to
- polarized sunglasses and photographic filters
- polarized-light stereoscopic cinema
- liquid-crystal displays with polarizers