Light-collecting device, light-collecting device array, exposure device and image-forming apparatus
US8081360B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 11, 2009 |
| Grant date | Dec 20, 2011 |
| Priority date | — |
| Expiry date | Dec 27, 2029 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N1/12
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A light-collecting device is provided, a light-collecting device, including: a first volume hologram recorded in a hologram recording layer by interference of a first spherical wave and a planar wave, the first spherical wave passing through a light path of diffused light which radiates from a light incident point, passes through the hologram recording layer and spreads to a predetermined diameter; and a second volume hologram recorded in the hologram recording layer by interference of a second spherical wave and the planar wave, the second spherical wave passing through a light path of converging light which radiates from the same side as the first spherical wave, passes through the hologram recording layer and converges at an image-forming point distanced from the hologram recording layer by a predetermined distance, the planar wave intersecting with the first spherical wave and the second spherical wave.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.