Laser projector with reduced speckle
US9122145B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 26, 2010 |
| Grant date | Sep 1, 2015 |
| Priority date | — |
| Expiry date | Jan 24, 2032 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N9/3135
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A projector using coherent light as a light source includes: one or more coherent light sources emitting coherent light beams; a beam scanner which changes a direction of the coherent light beam; and a beam splitter which splits a beam into multiple segments and changes a phase of light of each split segment, the beam splitter being located in an optical path between the beam scanner and the coherent light source. This projector reduces speckle noises. The beam splitter includes a pair of transparent substrates; a plurality of parallel electrodes disposed on each surface of the pair of transparent substrates, the pair of the parallel electrodes being disposed in a perpendicular direction to each other. Voltages are applied to the respective electrodes at predetermined time intervals so as to produce different potentials in a liquid crystal sandwiched by the transparent substrates.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.