Devices and methods for speckle reduction in scanning projectors
US10108022B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | May 21, 2018 |
| Grant date | Oct 23, 2018 |
| Priority date | — |
| Expiry date | May 21, 2038 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N9/3167
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
Devices and methods are described herein that use a first solid figure element, a polarizing beam splitter, and a second solid figure element or array of mirrors to reduce speckle in projected images. Specifically, laser light is generated and split into two portions having orthogonal polarizations. The first portion of laser light is reflected in the second solid figure element or the array of mirrors and is then spatially recombined with the second portion of laser light in the first solid figure element. The difference in path length followed by the two portions generates a temporal incoherence in the recombined laser light beam, and that temporal incoherence reduces speckle in the projected image.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.