Projection with curved speckle reduction element surface
US8172403B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | May 21, 2009 |
| Grant date | May 8, 2012 |
| Priority date | — |
| Expiry date | Apr 28, 2030 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B5/02
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
In a coherent light projection system including an image forming system, a relay system, a speckle reduction element, and a projection subsystem, the relay system can have a first f-number, and the projection subsystem can have a second f-number less than the first f-number. The relay system can have a first working distance, and the projection subsystem can have a second working distance less than the first working distance. The image forming system can project an initial image having a first size, and an intermediate image can have a second size greater than or equal to the first size. The speckle reduction element can have a curved surface through which the intermediate image is transferred. The speckle reduction element can include a lenslet arrangement formed on a surface thereof. The speckle reduction element can be moved in a direction parallel to an optical axis of the speckle reduction element.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.