Method for the formation of outline images corresponding to the peripheral outlines of document's images
US4828953A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 21, 1987 |
| Grant date | May 9, 1989 |
| Priority date | — |
| Expiry date | May 21, 2007 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03G13/045
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
The present invention relates to a method for forming an outline of an image. By this method, at first, an electrostatic latent image bearing member is charged and then irradiated to a negative image to form an electrostatic latent image. Thereafter, the irradiated member is re-charged with a scorotron charger while applying a voltage to a grid, said voltage being lower than the surface potential of the non-image portion of the latent image, being higher than the potential of the image portion of the latent image and being of the same porality as that of the charging. By this re-charging, in one embodiment, the outline portion of the image has lower potential than the other portion. Then, the outline portion of the image with lower potential is visualized with a reversal development by using a toner charged to a polarity same as the polarity of charging. Or in another embodiment, the outline portion of the image has higher potential than the other portion. Then, the outline portion of the image with high potential is visualized with a normal development by using a toner charged to a polarity opposite to the polarity of charging.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.