Contrast enhancement of electrographic imaging
US5163075A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 8, 1991 |
| Grant date | Nov 10, 1992 |
| Priority date | — |
| Expiry date | Aug 8, 2011 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03G15/222
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
The contrast of an electrographic image or a region of interest of an electrographic image having low contrast is enhanced by developing the electrographic image with toner using a development electrode which is biased to a potential which has a value near the average potential of the image but outside of the range of values of potential corresponding to image features selected for enhancement. The voltage potential of the electrographic image is measured to determine the average potential in the region of interest. The development electrode bias is set at a potential near the average potential but outside of the range of potentials corresponding to the image features selected for enhancement in the region of interest of the image. When developed with toner, the toner image has enhanced contrast. If the image is a xeroradiographic image, diagnostic capability of low contrast regions can be enhanced.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.