Optical device and image reading apparatus
US6115187A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 26, 1998 |
| Grant date | Sep 5, 2000 |
| Priority date | — |
| Expiry date | Oct 26, 2018 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N2201/03141
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
In an image sensor having a photoelectric conversion element for receiving light, an illumination unit, and a lens array in which a plurality of gradient index lens elements for focusing light reflected by an original onto the photoelectric conversion element are arrayed, part of the peripheral portion of the lens of the gradient index lens element in the radius direction contains a light absorber for absorbing light having a predetermined wavelength other than the wavelength distribution of light emitted by the illumination unit. With this arrangement, since the optical influences of the peripheral portion of the lens element, which degrade the lens resolution can be eliminated, and the lens elements can be accurately arrayed, there can be provided an image sensor which is free from crosstalk between the lens elements although the lens elements are arrayed in tight contact with each other, and has a large focal depth by changing the angular aperture, high performance, and hardly any performance variations in mass production, and an information processing system using the image sensor.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.