Bar code scanner with intuitive head aiming and collimated scan volume

• US 6,182,898 B1
• Filed: 11/22/1999
• Issued: 02/06/2001
• Est. Priority Date: 11/24/1993
• Status: Expired due to Term

• Current Assignee: Metrologic Instruments Incorporated (Honeywell International Inc.)
• Original Assignee: Metrologic Instruments Incorporated (Honeywell International Inc.)
• Inventors: Schmidt, Mark C., Wilz, David M. Sr., Rockstein, George B., Knowles, Carl H.
• Primary Examiner(s): Lee, Michael G
• Application Number:
  US09/444,587
• Time in Patent Office: 442 Days
• Field of Search: 235/462.45, 235/462.14, 235/462.17, 235/462.18, 235/462.2, 235/462.25, 235/462.32, 235/462.48, 235/472.01, 235/454
• US Class Current: 235/462.45
• CPC Class Codes: A61K 38/00 Medicinal preparations containing peptides peptides containing beta-lactam rings A61K31/00; cyclic dipeptides not having in their molecule any other peptide link than those which form their ring, e.g. piperazine-2,5-diones, A61K31/00; ergot alkaloids of the cyclic peptide type A61K31/48; containing macromolecular compounds having statistically distributed amino acid units A61K31/74; medicinal preparations containing antigens or antibodies A61K39/00; medicinal preparations characterised by the non-active ingredients, e.g. peptides as drug carriers, A61K47/00
• CPC Class Codes: A61K 39/00 Medicinal preparations containing antigens or antibodies materials for immunoassay G01N33/53
• CPC Class Codes: C07K 14/205 from Campylobacter (G)
• 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 2207/1017 Programmable
• 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: G06K 7/1443 : locating of the code in an image
• 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

Abstract

A fully automatic bar code symbol reading system comprising an automatic (i.e., triggerless) portable bar code symbol reading device with an omnidirectional projection laser scanning engine mounted within the head portion of its hand-supportable housing, and an associated base unit positioned within the data transmission range thereof without a physical wiring connection thereto. The hand-supportable bar code symbol reading device produces a narrowly confined scanning volume for omnidirectional scanning of code symbols presented therein, while preventing unintentional scanning of code symbols on nearby objects located outside thereof.

Claims

1. A laser scanner comprising:

(a) a hand-supportable housing having a light transmission window through which laser light can exit said hand-supportable housing, travel towards an object bearing a code symbol and reflect therefrom, and at least a portion of said reflected laser light travel back through said light transmission window and enter said hand-supportable housing;

(b) an optical bench mounted in said hand-supportable housing and having a longitudinal extent which extends along a central reference axis;

(c) a laser beam producing mechanism disposed within said hand-supportable housing for producing a laser beam;

(d) a laser beam sweeping mechanism mounted within said hand-supportable housing with respect to said optical bench for rotation about a rotational axis intersecting said central reference axis, where the intersection of said rotational axis and said central reference axis defines a central reference plane which extends along the longitudinal extent of said optical bench,

said laser beam sweeping mechanism having a plurality of rotating light reflective surfaces each being disposed at a different acute angle with respect to said rotational axis, for sequentially sweeping the laser beam about said rotational axis along a plurality of different paths;

(e) a stationary array comprised of a plurality of stationary light reflective surfaces mounted within said hand-supportable housing with respect to said optical bench and disposed substantially under said light transmission window;

wherein at least two of the plurality of said stationary light reflective surfaces are symmetrically disposed on opposite sides of said central reference plane, and closely adjacent said laser beam sweeping mechanism;

(f) a light collection subsystem disposed within said hand-supportable housing, and including

(1) a light collection element, mounted along said central reference plane and adjacent at least two of said stationary light reflective surfaces, for allowing the laser beam produced from said laser beam producing mechanism to pass along a portion of said central reference plane, to said laser beam sweeping means, for sweeping about said rotational axis thereof along said plurality of different paths, and

(2) a light receiver for receiving light from said light collection element at a point substantially within said central reference plane, and detecting the intensity of said received light and producing an electrical signal indicative of said detected intensity;

(g) a signal processor disposed within said hand-supportable housing, for processing said electrical signal and producing scan data representative of a scanned code symbol;

(h) a control mechanism within said hand-supportable housing for controlling the operation of said hand-supportable projection laser scanner so that, during scanner operation, the laser beam produced from said laser beam producing mechanism passes along a portion of said central reference plane, to at least one of the rotating light reflective surfaces of said laser beam sweeping mechanism, and as the laser beam sequentially reflects off a plurality of the rotating light reflective surfaces, the laser beam is repeatedly swept across a plurality of the stationary light reflective surfaces thereby producing a plurality of groups of plural scan lines, respectively, which are projected out through said light transmission window and intersect about a projection axis within a collimated scanning volume having an approximately columnar extent and extending from adjacent said light transmission window to at least about six inches therefrom so as to produce a highly collimated projected scanning pattern; and

(i) said hand-supportable housing being supportable relative to an object bearing a code symbol so that when a code symbol is presented within said collimated scanning volume,

(i) the code symbol is scanned omnidirectionally by said highly collimated scanning pattern,

(ii) at least a portion of the laser light reflected from said scanned code symbol is directed through said light transmission window, reflected off at least one of said stationary light reflective surfaces, and then reflected off at least one of said rotating light reflective surfaces of said laser beam sweeping means, and

(iii) thereafter said reflected laser light is collected by said light collection element, and received by said light receiver for detection, whereupon said electrical signal is produced for processing by said signal processor;

wherein said hand-supportable housing allows the user to easily control the direction of said projection axis by way of the handle portion of said hand-supportable housing, and thus align said collimated scanning volume with the bar code symbol on the object to be scanned and identified.

2. The laser scanner of claim 1, wherein said signal processor further comprises a data processor for decoding said scan data and producing data representative of said scanned code symbol.

3. The laser scanner of claim 1, wherein said different acute angles are selected so that the scan lines in each said group of scan lines are substantially equidistant from each other throughout at least a range of distances from said light transmission window.

4. The laser scanner of claim 1, wherein said laser beam producing mechanism comprises a laser diode mounted with respect to said optical bench.

5. The laser scanner of claim 1, wherein said first, second, third, and fourth stationary light reflective surfaces comprise first, second, third, and fourth mirrors, respectively.

6. The laser scanner of claim 1, wherein said hand-supportable housing has a head portion and handle portion extending from said head portion, and said light transmission window is disposed within said head portion.

7. The laser scanner of claim 1, wherein said highly collimated scanning pattern is oriented along the longitudinal extent of said hand-supportable housing so as to facilitate scanning of code symbols presented to said collimated scanning volume.

8. The laser scanner of claim 1, which further comprises a scanner support stand positionable upon a counter surface, and including a supporting mechanism for supporting said hand-supportable housing in any one of a plurality of positions above said counter surface so that said highly collimated scanning pattern is projected about said projection axis above said counter surface in any one of a plurality of orientations corresponding to said plurality of positions.

9. The laser scanner of claim 1, wherein said optical bench comprises a shock-mounted support structure upon which said stationary light reflective surfaces are mounted.

10. The laser scanner of claim 1, wherein said light receiver comprises a photodetector.

11. The laser scanner of claim 10, wherein said photodetector is located on a circuit board, at a height above said laser beam sweeping mechanism, substantially within said central reference plane.

12. The laser scanner of claim 1, wherein said code symbol is a bar code symbol.

13. The laser scanner of claim 1, wherein said light collecting element is a light collecting mirror having a focal distance, substantially at which said light receiver is located.

14. The laser scanner of claim 1, wherein

each scan line in a first group of scan lines is substantially parallel to each other scan line in said first group of scan lines, and

each scan line in a second group of scan lines is substantially parallel to each other scan line in said second group of scan lines.

15. An automatic projection laser scanning system comprising:

a hand-supportable housing having a light transmission aperture through which visible light can exit and enter into said hand-supportable housing;

an object detector in said hand-supportable housing, for detecting an object located in a scanning volume extending externally from said hand supportable housing, and automatically generating an activation signal in response to the detection of said object located therein;

an activatable scan data reading mechanism in said hand-supportable housing, for reading scan data from a detected object located in said scanning volume, said scan data reading mechanism including;

a laser beam generator for generating a visible laser beam and directing said visible laser beam through said light transmission aperture and into said scanning volume,

a laser beam scanner for repeatedly scanning said visible laser beam so as to produce a highly collimated scanning pattern of approximately columnar extent within said scanning volume, for scanning a code symbol on said detected object presented therein,

a laser light detector for detecting the intensity of laser light reflected off said bar code symbol and passing through said light transmission aperture as said visible laser beam is repeatedly scanned within said scanning volume, and

a receiver for automatically producing scan data indicative of said detected intensity;

an activatable scan data processor for processing produced scan data so as to detect and decode said bar code symbol on said detected object, and automatically producing symbol character data representative of said decoded bar code symbol; and

a control mechanism for controlling the operation of said automatic bar code symbol reading system;

wherein said hand-supportable housing allows the user to control the direction of said projection axis by way of the handle portion of said hand-supportable housing, and thus align said approximately columnar scanning volume with the bar code symbol on the object to be scanned and identified.

16. The automatic projection laser scanning system of claim 15, wherein said laser beam generator comprises a laser diode.

17. The automatic projection laser scanning system of claim 15, wherein said bar code symbol has first and second envelope borders, and wherein said scan data processor comprises a detector adapted to detect the first and second envelope borders of said bar code symbol, and a mechanism for decoding said detected bar code symbol.

18. The automatic projection laser scanning system of claim 15, wherein said object detector comprises a receiver for receiving energy reflected from an object within an object detection field defined external to said housing and having an essentially volumetric extent, and

wherein said highly collimated scanning pattern is characterized by at least one scanning plane having an essentially planar extent, and

wherein said object detection field spatially encompasses at least a portion of said highly collimated scanning pattern.

19. The automatic projection laser scanning system of claim 15, wherein said laser beam generator is operated in a pulsed laser mode so as to generate a pulsed visible laser beam, which is directed through said light transmission aperture and repeatedly scanned across said highly collimated scanning pattern and said bar code symbol on said detected object.

20. The automatic projection laser scanning system of claim 19, wherein said object detector includes

a transmitter for transmitting a pulse signal through a first optical element and into said scanning volume,

a signal receiver for receiving said transmitted pulse signal reflected off said object in said scanning volume, and

a signal comparator for comparing said received pulse signal with said transmitted pulse signal and automatically generating an activation signal indicative of the presence of said object in said scanning volume.

21. The automatic projection laser scanning system of claim 15, wherein said hand-supportable housing comprises a head portion and a handle portion, and wherein said object detector and said activatable scan data processor are located in said head portion.

22. The automatic projection laser scanning system of claim 20, wherein said transmitter comprises an infra-red light source in said hand-supportable housing for producing an infra-red light pulse which is transmitted through said first optical element into said scanning volume, and wherein said receiver comprises an infra-red light detector and a second optical element for focusing reflected infra-red light pulses onto said infra-red light detector.

23. A laser scanner comprising:

(a) a hand-supportable housing having a light transmission window through which laser light can exit said hand-supportable housing, travel towards an object bearing a code symbol and reflect therefrom, and at least a portion of said reflected laser light travel back through said light transmission window and enter said hand-supportable housing;

at least some of the exited laser light and at least some of the reflected laser light traveling approximately in a longitudinal direction extending along a central reference axis;

(b) a laser beam producing mechanism disposed within said hand-supportable housing for producing a laser beam;

(c) a laser beam sweeping mechanism mounted within said hand-supportable housing for rotation about a rotational axis intersecting said central reference axis, where the intersection of said rotational axis and said central reference axis defines a central reference plane;

said laser beam sweeping mechanism having a plurality of rotating light reflective surfaces each being disposed at a different acute angle with respect to said rotational axis, for sequentially sweeping the laser beam about said rotational axis along a plurality of different paths;

(d) a stationary array comprised of a plurality of stationary light reflective surfaces mounted within said hand-supportable housing;

wherein at least two of the plurality of said stationary light reflective surfaces are symmetrically disposed on opposite sides of said central reference plane, and adjacent to said laser beam sweeping mechanism;

(e) a light collection mechanism disposed within said hand-supportable housing, and including

(1) a light collection element, mounted along said central reference plane and adjacent at least two of said stationary light reflective surfaces, for allowing the laser beam produced from said laser beam producing mechanism to pass along a portion of said central reference plane, to said laser beam sweeping mechanism, for sweeping about said rotational axis thereof along said plurality of different paths, and

(2) a light receiver for receiving light from said light collection element at a point substantially within said central reference plane, and detecting the intensity of said received light and producing an electrical signal indicative of said detected intensity;

(f) a signal processor situated within said hand-supportable housing, for processing said electrical signal and producing scan data representative of a scanned code symbol; and

(g) a control mechanism within said hand-supportable housing for controlling the operation of said hand-supportable projection laser scanner so that, during scanner operation, the laser beam produced from said laser beam producing mechanism passes along a portion of said central reference plane, to at least one of the rotating light reflective surfaces of said laser beam sweeping mechanism, and as the laser beam sequentially reflects off a plurality of the rotating light reflective surfaces, the laser beam is repeatedly swept across a plurality of the stationary light reflective surfaces thereby producing a plurality of groups of plural scan lines, respectively, which are projected out through said light transmission window and intersect about a projection axis within a collimated scanning volume having an approximately columnar extent and extending from adjacent said light transmission window to at least about six inches therefrom so as to produce a highly collimated projected scanning pattern.

24. The laser scanner of claim 23 further comprising a mechanism adapted for intuitive aiming of the hand-supportable housing such that:

(i) said hand-supportable housing is supportable relative to an object bearing a code symbol wherein, when a code symbol is presented within said collimated scanning volume;

(i) the code symbol is scanned omnidirectionally by said highly collimated scanning pattern,

(ii) at least a portion of the laser light reflected from said scanned code symbol is directed through said light transmission window, reflected off at least one of said stationary light reflective surfaces, and then reflected off at least one of said rotating light reflective surfaces of said laser beam sweeping means, and

(iii) thereafter said reflected laser light is collected by said light collection element, and received by said light receiver for detection, whereupon said electrical signal is produced for processing by said signal processor;

and wherein said hand-supportable housing is adapted to permit a user to control the direction of said projection axis by way of the handle portion of said hand-supportable housing, and thus align said collimated scanning volume with the bar code symbol on the object to be scanned and identified.