Production of holograms
US4992346A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 19, 1989 |
| Grant date | Feb 12, 1991 |
| Priority date | — |
| Expiry date | Dec 19, 2009 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03C5/26
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
There is described a method of processing exposed holographic material to obtain holograms having a broader band replay a hologram which is of the silver halide in gelatin binder type which method comprises holographically exposing the holographic material by use of coherent light, developing the holographic image by a chemical process and then treating the material sequentially either firstly with a solution of an anionic surfactant which comprises at least one alkyl group having at least four carbon atoms and then with a solution of a quaternary ammonium compound which comprises at least one alkyl group having from 10 to 18 carbon atoms or a polymeric compound which comprises at least one quaternary ammonium group in the repeating unit or firstly with a solution of said quaternary ammonium compound or polymeric compound and then with a solution of an anionic surfactant, the material being subjected to a silver bleaching step at one stage after development. Preferably the anionic surfactant is present either in an acid stop bath after the development bath or in the bleach bath which is an acid bath. Then after the bleach bath the material is treated with the aqueous solution of th…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.