Drum scanner focusing system
US5410420A · kind A · utility
1Cited by
4References
7Claims
0Family size
Inventors
Key dates
| Filing date | Apr 14, 1993 |
| Grant date | Apr 25, 1995 |
| Priority date | — |
| Expiry date | Apr 14, 2013 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N1/028
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A focusing system for the optical head of a rotary drum scanner establishes focus quickly and automatically by iteratively scanning a line of a document on the drum and repeatedly adjusting the focus of the head in accordance with a focus optimizing function until the region of optimal focus is found.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.