Holographic laser scanning system for omni-directional laser scanning of bar code symbols with 3-D scanning volume having a large depth of field

• US 6,024,282 A
• Filed: 10/03/1997
• Issued: 02/15/2000
• Est. Priority Date: 08/17/1994
• Status: Expired due to Fees

• Current Assignee: Metrologic Instruments Incorporated (Honeywell International Inc.)
• Original Assignee: Metrologic Instruments Incorporated (Honeywell International Inc.)
• Inventors: Dickson, LeRoy, Amundsen, Thomas, Knowles, Carl Harry, Groot, John
• Primary Examiner(s): LE, THIEN MINH
• Application Number:
  US08/943,239
• Time in Patent Office: 865 Days
• Field of Search: 235/462.01, 235/462.24, 235/462.25, 235/472.01, 235/472.02, 359/17, 359/18
• US Class Current: 235/462.01
• CPC Class Codes: B82Y 15/00 Nanotechnology for interacting, sensing or actuating, e.g. quantum dots as markers in protein assays or molecular motors
• CPC Class Codes: G02B 26/10 Scanning systems
• CPC Class Codes: G02B 26/106 having diffraction gratings as scanning elements, e.g. holographic scanners holographic optical elements G02B5/32, holography G03H
• CPC Class Codes: G06K 17/0022 arrangements or provisious for transferring data to distant stations, e.g. from a sensing device "transfer between computer elements G06F13/00 "; data-transmission H04L
• CPC Class Codes: G06K 2207/1012 Special detection of object
• CPC Class Codes: G06K 2207/1013 Multi-focal
• CPC Class Codes: G06K 2207/1016 Motor control or optical moving unit control
• CPC Class Codes: G06K 2207/1017 Programmable
• CPC Class Codes: G06K 2207/1018 Source control
• CPC Class Codes: G06K 7/10 by electromagnetic radiation, e.g. optical sensing; by corpuscular radiation
• CPC Class Codes: G06K 7/10564 Light sources
• CPC Class Codes: G06K 7/10584 Source control
• CPC Class Codes: G06K 7/10594 Beam path
• CPC Class Codes: G06K 7/10603 Basic scanning using moving elements
• CPC Class Codes: G06K 7/10663 using hologram
• CPC Class Codes: G06K 7/10673 Parallel lines
• CPC Class Codes: G06K 7/10693 for omnidirectional scanning
• CPC Class Codes: G06K 7/10702 Particularities of propagating elements, e.g. lenses, mirrors G06K7/10831 takes precedence
• CPC Class Codes: G06K 7/10792 Special measures in relation to the object to be scanned
• CPC Class Codes: G06K 7/10801 Multidistance reading
• CPC Class Codes: G06K 7/10811 : Focalisation
• 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: G06K 7/10871 : randomly oriented data-fields, code-marks therefore, e.g. concentric circles-code
• CPC Class Codes: G06K 7/10881 : constructional details of hand-held scanners
• CPC Class Codes: G06K 7/10891 : the scanner to be worn on a finger or on a wrist
• CPC Class Codes: G06K 7/109 : adaptations to make the hand-held scanner useable as a fixed scanner
• CPC Class Codes: G06K 7/14 : using light without selection of wavelength, e.g. sensing reflected white light G06K7/10831 - G06K7/1097 take precedence
• CPC Class Codes: G07F 9/002 : Vending machines being part of a centrally controlled network of vending machines
• 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 1/0054 : with control of supplementary check-parameters, e.g. weight or number of articles

Abstract

A holographic laser scanning system for producing a highly defined 3-D scanning volume for omni-directional laser scanning of bar code symbols therein having a minimum element width on the order of about 0.017 inches or less. The holographic laser scanning system comprise a housing, a plurality of laser sources, a holographic scanning disc and a plurality of photodetectors. The plurality of lasr sources are disposed within the housing, for producing a plurality of laser beams. The holographic scanning disc is disposed within the housing, and has a plurality of holographic optical elements for scanning the laser beams and producing a plurality of laser scanning planes for scanning a code symbol. Each laser scanning plane has predefined beam characteristics and is spatially confined within a highly-defined 3-D scanning volume having at least three focal zones, a depth of field of at least 10 inches, and a scanning volume of at least 1,440 cubic inches. The plurality of laser scanning planes intersect within the highly defined 3-D scanning volume and the predefined beam characteristics of the laser scanning planes cooperate within the highly defined 3-D scanning volume so as to produce an omnidirectional laser scanning pattern for omnidirectional scanning therewithin, code symbols having a minimum element width on the order of about 0.017 inches or less.

Claims

1. A holographic laser scanning system for producing a highly defined 3-D scanning volume for omni-directional laser scanning of bar code symbols therein having a minimum element width on the order of about 0.017 inches or less, said holographic laser scanning system comprising:

a housing;

a plurality of laser sources disposed within said housing, for producing a plurality of laser beams;

holographic scanning disc disposed within said housing, rotating about an axis of rotation, and having a plurality of holographic optical elements for scanning said plurality of laser beams and producing a plurality of laser scanning planes for scanning a code symbol, each said laser scanning plane having predefined beam characteristics and being spatially confined within a highly-defined 3-D scanning volume having at least three focal zones, a depth of field of at least 10 inches, and a scanning volume of at least 1,440 cubic inches;

a plurality of photodetectors disposed within said housing, each said photodetector being associated with one said laser source and being capable of detecting laser light reflected off a code symbol scanned by the laser beam produced by said associated laser source;

wherein said plurality of laser scanning planes intersect within said highly defined 3-D scanning volume and said predefined beam characteristics of said laser scanning planes cooperate within said highly-defined 3-D scanning volume so as to produce an omnidirectional laser scanning pattern for omnidirectional scanning therewithin, code symbols having a minimum element width on the order of about 0.017 inches or less.

2. The holographic laser scanning system of claim 1, wherein said highly-defined 3-D scanning volume is in the shape of a 3-D polygonal shaped object.

3. The holographic laser scanning system of claim 2, wherein said 3-D polygonal shaped object has at least four substantially rectangular shaped side surfaces.

4. The holographic laser scanning system of claim 1, wherein each said laser source comprises a laser diode for producing a visible laser beam.

5. The holographic laser scanning system of claim 1, wherein said laser diodes are symmetrically arranged about said holographic scanning disc.

6. The holographic laser scanning system of claim 1, wherein each said holographic optical element is a volume hologram.

7. The holographic laser scanning system of claim 6, wherein each said volume hologram is a transmission-type volume hologram.

8. The holographic laser scanning system of claim 1, wherein said plurality of laser sources comprises at least three laser diodes, said plurality of holographic optical elements comprises at least sixteen volume transmission-type holograms, and said plurality of laser scanning planes comprises at least forty-eight laser scanning planes.