Method for despeckling in laser display systems
US9063357B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 27, 2012 |
| Grant date | Jun 23, 2015 |
| Priority date | — |
| Expiry date | Feb 21, 2033 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02F2203/03
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A device used in laser display systems for despeckling includes a liquid crystal cell disposed in sandwiched relation between an input and a grounded electrode. A glass cover overlies each electrode. In a first embodiment, the cell may include vertically or randomly oriented liquid crystal molecules and the liquid crystal cell is larger than a laser beam in size for random phase modulation or retardation. Light loss due to diffraction and scattering are substantially eliminated in the absence of pixel structures. In another embodiment, the input electrode is divided into two separate parts. Vertically aligned liquid crystal molecules rotate and follow field fringes created by applying a first voltage to the input electrodes. Additional embodiments include a device that has two wedge-shaped liquid crystal layers, a device that includes plural field-induced gradient index prisms, a device including a tilted mirror, and composite devices.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.