Tone reproduction method and apparatus
US4701811A · kind A · utility
22Cited by
3References
3Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | May 14, 1985 |
| Grant date | Oct 20, 1987 |
| Priority date | — |
| Expiry date | May 14, 2005 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N1/4057
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
In a half-tone recording method and apparatus, half-tone expressing units, each consisting of several recording picture elements, express gradations of density in a document. The recording picture elements in the units are assigned various half-tone levels with the half tone level of at least one of the recording picture elements both increasing and decreasing as the gradation of the half-tone expressing unit increases.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.