Image processing apparatus and method with locking feature
US6570708B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 18, 2000 |
| Grant date | May 27, 2003 |
| Priority date | — |
| Expiry date | Jan 24, 2021 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06V10/89
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
An optical coherent processor or correlator for processing an input image produced by an imaging device illuminated by a coherent light source utilizes an optical key for preventing unauthorized use of the processor. The principle underlying processing apparatus and method according to the invention uses an optical lock in combination with an encoded software key superimposed on a filter image. The optical lock, which is preferably in hardware form, consists of a first optical mask implementing a locking mask function that is preferably complex (phase and/or amplitude), which first optical mask is included in the optical path of the processor. The mask is fixed during assembly of the processor or correlator and a unique pattern is encoded thereon. The software key consists of a pattern defined by a key mask function that is displayed preferably using a spatial light modulator as part of a second optical mask included on the processor optical path. The key mask function is designed to compensate for the wave-front distortion generated by the locking mask function of the first optical mask. Therefore, an optical processor or correlator provided with its unique hardware lock cannot ge…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.