High-efficiency reflective holographic diffuser and method for making thereof
US5721630A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 12, 1996 |
| Grant date | Feb 24, 1998 |
| Priority date | — |
| Expiry date | Mar 12, 2016 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B5/32
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A high-efficiency holographic diffuser is provided, the holographic diffuser being comparatively thin, yet characterized by good optical density along a broad bandwidth. In particular, the high-efficiency holographic diffuser comprises a light-transmissive substrate; and a planar hologram layer, the planar hologram layer having an interference pattern holographically recorded therein, the interference pattern producing a diffuse light pattern in reflection when irradiated with light, the interference pattern being resultant of the combination of an incident wavefront and a counterpropagating wavefront substantially coherent with the incident wavefront, the incident coherent wavefront having impinged upon the planar hologram layer from a first side, the counterpropagating coherent wavefront having impinged upon the planar hologram layer from a second side opposite the first side, the incident coherent wavefront being a diffused coherent wavefront, the counterpropagating coherent wavefront also being a diffused coherent wavefront. The high-efficiency holographic diffuser can be formed by diffusing a coherent wavefront prior to its incidence on a holographic recording medium, transmit…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.