Image reader and method for correcting the quantity of light source
US6975435B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 23, 2000 |
| Grant date | Dec 13, 2005 |
| Priority date | — |
| Expiry date | Feb 23, 2020 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N2201/044
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
In the correction of the quantity of light of a light source used in an image reader which irradiates an original document with the light source, receives the reflected light by a CCD and reads the original document image, at the time of a document moving mode in which the document moves, correction of the quantity of irradiation light of the light source is performed by reading a first standard white board which extends over the whole area in the main scanning direction, prior to the initiation of readout of the moving document, and upon initiation of readout of the moving document, a second standard white board arranged outside the document passing area is read by using the same light source, with the read operation of the moving document, and correction of the quantity of irradiation light of the light source is performed based on the reflected light from the second white board.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.