Extended depth of field imaging system using chromatic aberration
US7626769B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 22, 2007 |
| Grant date | Dec 1, 2009 |
| Priority date | — |
| Expiry date | Mar 22, 2027 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06K7/10702
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
An imaging system (FIG. 3) is disclosed that has a wavelength dependent focal shift caused by longitudinal chromatic aberration in a lens assembly (203) that provides extended depth of field imaging due to focal shift (213,214) and increased resolution due to reduced lens system magnification. In use, multiple wavelengths of quasi-monochromatic illumination, from different wavelength LEDs (206,207) or the like, illuminate the target, either sequentially, or in parallel in conjunction with an imager (200) with wavelength selective (colored) filters. Images are captured with different wavelengths of illumination that have different focus positions (208,209), either sequentially or by processing the color planes of a color imager separately. Extended depth of field, plus high resolution are achieved. Additionally, information about the range to the target can be determined by analyzing the degree of focus of the various colored images.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.