Method and apparatus for reading color images using a plurality of color light sources in which one of the light sources is turned on continuously
US4652913A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 11, 1984 |
| Grant date | Mar 24, 1987 |
| Priority date | — |
| Expiry date | Apr 11, 2004 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N1/484
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
In a method and an apparatus for reading a color image wherein the color image is illuminated and scanned by light from a plurality of light sources having different spectral properties to read the color image on the basis of the reflected light therefrom, at least one light source of the light sources is kept turned on during the scanning operation of the color image, thereby eliminating any problems resulting from its after-glow; and at least one light source of the light sources other than that kept turned on is repeatedly turned on and off with a period corresponding to the period of the scanning operation so as to project the light from the single and plural light sources selected from the light sources, at least once respectively, upon the scanned portions of the color image. The color image is read by detecting colors on the scanned portions of the color image on the basis of levels of the light reflected from the color image. A variety of colors may be detected by the present invention including red, blue, black and cyan. In addition, the present invention also teaches the use of color filters to eliminate the potential after-glow effect of color fluorescent lamps.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.