Lighting unit and image scanner using same
US9167121B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 24, 2012 |
| Grant date | Oct 20, 2015 |
| Priority date | — |
| Expiry date | Oct 24, 2032 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03B27/54
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A lighting unit is provided with: LED arrays in which light-emitting elements are positioned in an array in a main scanning direction; cylindrical parabolic mirrors that project light emitted from the LED arrays on an illumination region of an illuminated item; and a housing that houses or holds the LED arrays and the cylindrical parabolic mirrors. Each cylindrical parabolic mirror forms a shape in which a cylindrical paraboloid having curvature with respect to a sub-scanning direction has been clipped by an axial plane that is perpendicular to the vertex of the cylindrical paraboloid in the main scanning direction. The LED arrays are positioned so as to include the focal position of the cylindrical paraboloid in the light-emitting region, the central axis in the light-emitting direction being perpendicular to the axial plane.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.