Double beam systems for forming improved holograms
US4458978A · kind A · utility
18Cited by
7References
29Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Jun 1, 1981 |
| Grant date | Jul 10, 1984 |
| Priority date | — |
| Expiry date | Jun 1, 2001 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03H2001/0232
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
The systems of the invention form improved reflection and transmission holograms utilizing two beams and eliminating all of the higher energy spurious holographic recordings that are caused by reflections of rays from the outer surfaces of the cover plates. The systems provide movement of the cover plate or movement of the substrate and recording medium during the recording period to prevent formation of the spurious recordings. In some arrangements of the invention, global phase shifters are utilized to maintain the phase of the primary rays forming the desired hologram at a high level.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.