CCD Color image sensor with a light source having a spectrum distribution characteristic having peaks at 470 nm and 590 nm and having no wavelengths above 700 nm
US4716456A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Sep 22, 1986 |
| Grant date | Dec 29, 1987 |
| Priority date | — |
| Expiry date | Sep 22, 2006 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N1/484
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
In a color image sensor, CCD chips having peculiar spectrum distribution characteristics are arranged in two rows on a base with the CCD chips in one row staggered with respect to those in the other row. A pair of convergent rod lens arrays is located between a color document and the array of CCD chips for projecting an image of the document onto the CCD element array. The CCD elements each having a plurality of photosensitive areas with white, yellow and cyan filters, or yellow, green and cyan filters, or red, green and blue filters, provided thereon. A pair of fluorescent lamps for illuminating the document is each provided in the neighborhood of each of the pair rod lens arrays. They have spectrum distribution characteristics not covering wavelengths above 700 nm. One of them has a spectrum distribution characteristic with a peak substantially at 450 nm, and the other has a spectrum distribution characteristic with a peak substantially at 590 nm. The composite spectrum distribution characteristic of the two lamps has peaks substantially at 480 nm and 590 nm, and has no wavelengths above 700 nm.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.