Device for optically multiplexing a laser beam

• US 20080142601A1
• Filed: 10/30/2007
• Published: 06/19/2008
• Est. Priority Date: 11/24/2000
• Status: Active Grant

• Current Assignee: Metrologic Instruments Incorporated (Honeywell International Inc.)
• Original Assignee: Metrologic Instruments Incorporated (Honeywell International Inc.)
• Inventors: Zhu, Xiaoxun, Veksland, Michael, Ren, Jie, Knowles, C. Harry, Xian, Tao, Liu, Yong, Good, Timothy, Giordano, Patrick, Schmidt, Mark, Kotlarsky, Anatoly, Tao, Xi, Liu, JiBin, Essinger, Steven, Gardner, John, Kearney, Sean, Ellis, Duane, Ciarlante, Nicholas, Hernandez, Mark, Zhuo, Ming, Furlong, John A.
• Granted Patent: US 7,762,465 B2
• Time in Patent Office: Days
• US Class Current: 235/462.42
• CPC Class Codes: A47F 9/046 Arrangement of recording means in or on check-out counters record carriers or readers per se G06K
• CPC Class Codes: G02B 27/48 Laser speckle optics
• CPC Class Codes: G06K 2207/1012 Special detection of object
• CPC Class Codes: G06K 7/10544 by scanning of the records by radiation in the optical part of the electromagnetic spectrum
• CPC Class Codes: G06K 7/10564 Light sources
• CPC Class Codes: G06K 7/10574 Multiple sources
• CPC Class Codes: G06K 7/10613 by rotation, e.g. polygon
• CPC Class Codes: G06K 7/10623 Constructional details
• CPC Class Codes: G06K 7/10693 for omnidirectional scanning
• CPC Class Codes: G06K 7/10712 Fixed beam scanning
• CPC Class Codes: G06K 7/10722 Photodetector array or CCD scanning
• CPC Class Codes: G06K 7/10732 Light sources
• CPC Class Codes: G06K 7/10782 Slot readers
• CPC Class Codes: G06K 7/10792 Special measures in relation to the object to be scanned
• CPC Class Codes: G06K 7/10851 Circuits for pulse shaping, amplifying, eliminating noise signals, checking the function of the sensing device basic electronic circuitry H03
• CPC Class Codes: G06K 7/10861 sensing of data fields affixed to objects or articles, e.g. coded labels postal sorting B07C3/14, conveying articles B65G47/48
• CPC Class Codes: G06Q 20/208 Input by product or record sensing, e.g. weighing or scanner processing
• CPC Class Codes: G06Q 30/06 Buying, selling or leasing transactions
• CPC Class Codes: G06V 10/141 Control of illumination
• CPC Class Codes: G07G 1/0036 Checkout procedures
• CPC Class Codes: G07G 1/0045 : with a code reader for reading of an identifying code of the article to be registered, e.g. barcode reader or radio-frequency identity [RFID] reader
• CPC Class Codes: G07G 3/00 : Alarm indicators, e.g. bells
• CPC Class Codes: G07G 3/006 : False operation

Abstract

A device for optically multiplexing a laser beam, having a glass plate construction with an input surface and an output surface, and bearing reflective and semi-reflective coatings arranged so as to optically multiplex an input laser beam entering the input surface, into multiple spatial-coherence reduced output laser beams exiting from the output surface. Through such optical multiplexing, and recombination, the coherence of the resulting laser beam is substantially reduced, as is the power of speckle pattern noise observed at an image detection array detecting an image of an object illuminated by said laser beam.

Claims

1. A device for optically multiplexing a laser beam, comprising:

a single glass plate having an input surface and an output surface, and bearing reflective and semi-reflective coatings on said input and output surfaces, arranged so as to optically multiplex an input laser beam entering said input surface, into multiple output laser beams which are recombined into a spatial-coherence reduced laser beam exiting from said output surface.

2. The device of claim 1, wherein said spatial-coherence reduced output laser beam is planarized into a composite substantially planar laser illumination beam (PLIB) by a multi-cylinder planarizing-type illumination lens array disposed in close proximity to said output surface.

3. The device of claim 1, wherein said laser beam is generated from a visible laser diode.

4. An optical beam multiplexer (OMUX) device comprising:

a pair of glass plates coupled together and having an input surface, an interface surface and n output surface, and bearing reflective and semi-reflective coatings, and deployable in a laser bean despeckling module having a laser beam source, arranged so as to optically multiplex an input laser beam entering said input surface, into multiple output laser beams which are recombined into a spatial-coherence reduced laser beam exiting from said output surface.

5. The OMUX device of claim 4, wherein said spatial-coherence reduced output laser beam is planarized into a composite substantially planar laser illumination beam (PLIB) by a multi-cylinder planarizing-type illumination lens array disposed in close proximity to said output surface.

6. The OMUX device of claim 4, wherein said laser beam is generated from a visible laser diode.