Laser code symbol scanning system with high-resolution 2-D scanning field steerable with 3-D scanning volume

• US 6,457,646 B1
• Filed: 09/17/1999
• Issued: 10/01/2002
• 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:
  US09/398,741
• Time in Patent Office: 1,110 Days
• Field of Search: 235/462, 235/472, 235/494, 235/454, 235/470, 235/468, 235/375
• US Class Current: 235/472.01
• 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 provisions 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

The first scanner generates an omnidirectional laser scanning pattern within a large 3-D scanning volume in order to detect the location of a code symbol therewithin and produce data indicative of its location therewithin. Using this location data, the second scanner produces a high density scanning pattern to aggressively scan the region in which the code symbol has been detected, and collect scan data for decode processing. In the illustrative embodiment, the first scanner is realized as a multiple-focal plane holographic scanner, whereas the second scanner is realized as a high-speed 2-D scanner. By virtue of the system and method of the present invention, it is now possible to read bar code symbols located anywhere within very large volume of space, with a high degree of accuracy hitherto impossible using prior art techniques.

Claims

1. A code symbol reading system comprising:

a first scanner for automatically scanning a laser beam and producing a first laser scanning pattern within a 3-D scanning volume for scanning a code symbol on an object located within said 3-D scanning volume, detecting the location of said code symbol within said 3-D scanning volume, and producing location specifying data indicative of said location of said code symbol; and

a second scanner, being responsive to said location specifying data produced by said first scanner, for producing a second laser scanning pattern and moving said second laser scanning pattern within said 3-D scanning volume so as to automatically scan the region in which the code symbol is detected, and collecting scan data for decode processing.

2. The code symbol reading system according to claim 1, wherein said first scanner is a holographic laser scanner for producing said 3-D scanning volume using multiple focal zones and a depth of field of at least 24 inches.

3. The code symbol reading system of claim 1, wherein said second scanner is a 2-D type scanner for producing said second laser scanning pattern within a 2-D scanning field.

4. The code symbol reading system of claim 3 which further comprises means, responsive to said location specifying data, for steering said second laser scanning pattern within said 3-D scanning volume about said region in which said code symbol is detected.

5. The code symbol reading system of claim 4, wherein said 2-D type scanner is a CCD-based scanner having means for capturing scan data within said 2-D scanning field about said region.