Image reader for an image recording apparatus
US4989100A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jun 22, 1989 |
| Grant date | Jan 29, 1991 |
| Priority date | — |
| Expiry date | Jun 22, 2009 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N1/4076
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An image reader for an image forming apparatus has an array of CCD sensors in the form of chips which are arranged in a zigzag configuration along an image reading line. A reference white plate is located in association with the position of and outside of the effective image reading range of one of two CCD sensors which are situated at opposite ends of the array. The CCD sensor with which the reference white plate is associated produces a reference white signal by reading the reference white plate. The output gain of this CCD sensor is controlled on the basis of the reference white signal. The reference white signal is added to output signals of the other CCD sensors in the form of a pilot signal, whereby the output gains of the other CCD sensors are controlled.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.