Digital illumination and imaging subsystem employing despeckling mechanism employing high-frequency modulation of laser diode drive current and optical beam multiplexing techniques
US7665665B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 30, 2007 |
| Grant date | Feb 23, 2010 |
| Priority date | — |
| Expiry date | Feb 7, 2028 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06K2207/1012
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A digital illumination and imaging system employing one or more planar laser illumination modules (PLIMs) each including: (i) a laser illumination source driven preferably by high frequency modulated (HFM) diode current drive circuitry; (ii) a beam collimating optics disposed beyond the laser source; (ii) an optical beam multiplexer (OMUX) device disposed beyond the collimating optics; and (iv) a planarizing-type illumination lens array disposed beyond the OMUX device, and arranged for generating a plurality of substantially planar coherence-reduced laser illumination beams (PLIBs) that form a composite substantially planar laser illumination beam (PLIB) having substantially reduced spatial/temporal coherence. A digital image detection array for detecting digital images of an object illuminated by the composite substantially planar laser illumination beam. By virtue of the present invention, the power of speckle pattern noise, observed in a digital image of an object detected at the digital image detection array, is substantially reduced when the digital image is formed using the substantially planar laser illumination beam.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.