Variable acuity non-linear projection system
US5071209A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 7, 1990 |
| Grant date | Dec 10, 1991 |
| Priority date | — |
| Expiry date | May 7, 2010 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B2027/0145
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
The invention provides a non-linear projection system, which includes a variable acuity non-linear holographic optical element (HOE), and an apparatus for creating the HOE. The projection system comprises a computer, a light valve which projects images generated by the computer, a lens train for focusing the images projected by the light valve, an HOE for the non-linear refraction of the focused images and a hemispherical viewing screen. The system additionally provides means for maintaining the center of the projected images in alignment with center of the field of view of an observer. The variation of the pixel size and spacing created by the system matches the variation of the human visual acuity of the observer permitting a realistic view to be presented while requiring a minimum of computer data to be generated and projected. The apparatus for creating the HOE utilizes a laser beam, three lens trains and a holographic recording medium. A procedure for utilizing the apparatus to record the HOE over a large portion of its surface area is also disclosed.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.