Bioptical holographic laser scanning system

• US 6,758,402 B1
• Filed: 04/18/2000
• Issued: 07/06/2004
• 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: Good, Timothy, Dickson, LeRoy, Check, Frank, Groot, John
• Primary Examiner(s): Le, Thien M.
• Application Number:
  US09/551,887
• Time in Patent Office: 1,540 Days
• Field of Search: 235/462-2-4, 235/472.01, 235/472.02, 235/472.03, 235/375, 235/494, 235/370
• US Class Current: 235/462.34
• 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 bioptical holographic laser scanning system employing a plurality of laser scanning stations about a holographic scanning disc having scanning facets with high and low elevation angle characteristics, as well as positive, negative and zero skew angle characteristics which strategically cooperate with groups of beam folding mirrors having optimized surface geometry characteristics. The system has an ultra-compact construction, ideally suited for space-constrained retail scanning environments, and, generate a 3-D omnidirectional laser scanning pattern between the bottom and side scanning windows during system operation. The laser scanning pattern of the present invention comprises a complex of pairs of quasi-orthogonal laser scanning planes, each composed by a plurality of substantially-vertical laser scanning planes for reading bar code symbols having bar code elements (i.e. ladder-type bar code symbols) that are oriented substantially horizontal with respect to the bottom scanning window, and a plurality of substantially-horizontal laser scanning planes for reading bar code symbols having bar code elements (i.e. picket-fence type bar code symbols) that are oriented substantially vertical with respect to the bottom scanning window.

Claims

1. A bioptical holographic laser scanning system comprising:

a bottom scanning window;

a side scanning window;

a holographic scanning disc supporting a plurality of holographic scanning facets; and

a plurality of laser scanning stations arranged about said holographic scanning disc;

wherein each laser scanning station has at least one laser beam folding mirror; and

wherein said laser scanning stations collectively produce a laser scanning pattern having a plurality of pairs of quasi-orthogonal laser scanning planes that are projected within predetermined regions of space contained within a 3-D scanning volume defined between said bottom and side scanning windows.

2. The bioptical holographic laser scanning system of claim 1, wherein said plurality of pairs of quasi-orthogonal laser scanning planes are produced using said holographic scanning disc supporting holographic scanning facets having high and low elevation angle characteristics and left, right and zero skew angle characteristics.

3. The bioptical holographic laser scanning system of claim 2, wherein said plurality of pairs of quasi-orthogonal laser scanning planes are capable of reading a bar code symbol that is orientated with bar code elements arranged in either a substantially vertical (i.e. picket-fence) or substantially horizontal (i.e. ladder) configuration with respect to said horizontal scanning window.

10. The bioptical holographic laser scanning system of claim 1, wherein the size of the laser beam folding mirrors employed at each said laser scanning station is minimized.

11. The bioptical holographic laser scanning system of claim 1, wherein blocking of light return paths by said laser beam folding mirrors is eliminated.

12. The bioptical holographic laser scanning system of claim 1, wherein mechanical interference between said laser beam folding mirrors is eliminated.

13. The bioptical holographic laser scanning system of claim 1, wherein the angles of the laser scanning beams at said horizontal scanning window is optimized.

14. The bioptical holographic laser scanning system of claim 1, wherein said laser scanning pattern provides 360 degrees of scan coverage at a POS station, while the internal mirror-space volume of the scanning system is minimized.

4. A bioptical holographic laser scanning system comprising:

a horizontal scanning window;

a vertical scanning window;

first, second, third and fourth laser scanning stations arranged about a holographic scanning disc supporting a plurality of holographic scanning facets;

wherein each laser scanning station includes one or more groups of laser beam folding mirrors; and

wherein said first and third laser scanning stations employ groups of laser beam folding mirrors and scanning facets having only high elevation characteristics and left and right skew angle characteristics so as to produce a plurality of pairs of quasi-orthogonal laser scanning planes capable of reading bar code symbol orientated with bar code elements arranged in either a substantially vertical (i.e. picket-fence) or substantially horizontal (i.e. ladder) configuration with respect to said horizontal scanning window.

5. The bioptical holographic laser scanning of claim 4, wherein said second laser scanning station employs a group of laser beam folding mirrors and scanning facets having only low elevation characteristics and zero skew angle characteristics so as to produce a plurality of pairs of quasi-orthogonal laser scanning planes capable of reading bar code symbol orientated with bar code elements arranged in either a substantially vertical (i.e. picket-fence) or substantially horizontal (i.e. ladder) configuration with respect to said horizontal scanning window.

6. The bioptical holographic laser scanning system of claim 4, wherein said fourth laser scanning station employs a group of laser beam folding mirrors and scanning facets having only high elevation characteristics and zero skew angle characterictics so as to produce a plurality of laser scanning planes capable of reading bar code symbol orientated with bar code elements arranged in either a substantially vertical (i.e. picket-fence) configuration with respect to said horizontal scanning window.

7. The bioptical holographic laser scanning system of claim 6, wherein said plurality of pairs of quasi-orthogonal laser scanning planes are produced using S-polarized laser beams directed incident said holographic scanning disc.

8. The bioptical holographic laser scanning system of claim 4, wherein four visible laser diodes (VLDs) symmetrically places about said holographic scanning disc are used create said plurality of pairs of quasi-orthogonal laser scanning planes.

9. The bioptical holographic laser scanning system of claim 4, wherein a single VLD is used to produce a scan pattern that is projected through said vertical scanning window so as to minimize crosstalk at said laser scanning stations.