GENERALIZED METHOD OF SPECKLE-NOISE PATTERN REDUCTION AND PARTICULAR FORMS OF APPARATUS THEREFOR BASED ON REDUCING THE SPATIAL-COHERENCE OF THE PLANAR LASER ILLUMINATION BEAM AFTER IT ILLUMINATES THE TARGET BY APPLYING SPATIAL INTENSITY MODULATION TECHNIQUES DURING THE DETECTION OF THE REFLECTED/SCATTERED PLIB
US6971576B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 30, 2002 |
| Grant date | Dec 6, 2005 |
| Priority date | — |
| Expiry date | Sep 30, 2023 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01S5/02325
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A planar laser illumination and imaging (PLIIM) based camera system capable of producing digital images with reduced levels of speckle-pattern noise. The PLIIM based camera system comprises a planar laser illumination array (PLIA) including a plurality of laser diodes for producing and projecting a planar laser illumination beam (PLIB) so as to illuminate an object as it is moving past said PLIIM based camera system. An image formation and detection (IFD) module is provided having a image detection array and imaging forming optics for providing the image detection array with a field of view (FOV). The PLIB and FOV are arranged in a coplanar relationship along the working range of the PLIIM based camera system so that the PLIB illuminates primarily within the FOV of the IFD module. A speckle-pattern noise reduction subsystem is integrated with the IFD, for reducing the spatial-coherence of said planar laser illumination beam (PLIB) after the PLIB has illuminated and reflected/scattered off the target object. The speckle-pattern noise reduction subsystem carries out a spatial intensity modulation technique after the reflection/scattering of the PLIB off the target, so that the laser …
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.