Automatically-triggered digital video-imaging based code symbol reading system for us in point-of-sale (POS) environment

• US 20080041957A1
• Filed: 06/13/2007
• Published: 02/21/2008
• Est. Priority Date: 11/13/2003
• Status: Active Grant

• Current Assignee: Metrologic Instruments Incorporated (Honeywell International Inc.)
• Original Assignee: Metrologic Instruments Incorporated (Honeywell International Inc.)
• Inventors: Zhu, Xiaoxun, Veksland, Michael, Good, Timothy, Kotlarsky, Anatoly, Hou, Richard, Meagher, Mark, Hu, Daniel, Au, Ka
• Granted Patent: US 7,770,798 B2
• Time in Patent Office: Days
• US Class Current: 235/462.42
• CPC Class Codes: G06K 7/10683 Arrangement of fixed elements
• 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 7/10801 Multidistance reading
• CPC Class Codes: G06K 7/10831 Arrangement of optical elements, e.g. lenses, mirrors, prisms optical elements per se G02B
• 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

Abstract

An automatic digital video-imaging based code symbol reading system for use in point of sale (POS) environments, employing automatic illumination control, multi-tier modular software architecture and digital video-imaging based code symbol reading techniques, which ensures the reliable reading of code symbols graphically represented in digital images, in high-throughput point-of-sale and other environments, while providing the versatility required to accommodate the different ways in which operators present objects for code symbol reading at POS environments.

Claims

1. An automatically-triggered digital video-imaging based code symbol reading system for reading code symbols on objects presented at point of sale (POS) environments, comprising:

a housing having an imaging window;

a digital image formation and detection subsystem, disposed in said housing, and having (i) image formation optics for projecting a field of view (FOV) from an area-type image detection array, through said imaging window and upon an object to be imaged during object illumination and video-imaging operations, and (ii) said area-type image detection array for detecting frames of digital video image data of the object during said object illumination and video-imaging operations;

an illumination subsystem, disposed in said housing, having an illumination array for producing a field of illumination in said FOV during said object illumination and video-imaging operations;

said illumination subsystem including (i) an illumination board supported within said housing and having a central aperture through which said FOV passes during object illumination and video-imaging operations, and on which said illumination array is mounted, and (ii) an assembly of lenses, supported on said illumination board, for focusing and/or shaping illumination emanating from said illumination array so as to produce said field of illumination within said FOV;

wherein said a central aperture in said illumination board is spatially aligned with said imaging window in said housing;

an automatic object detection subsystem, disposed in said housing, for automatically detecting the presence of the object in said FOV, and in response thereto, generating a trigger signal indicative of a triggering event;

an automatic illumination control subsystem, disposed in said housing, for controlling illumination produced from said illumination array during said object illumination and video-imaging operations, said automatic illumination control subsystem including circuitry for providing drive signals to said illumination array;

a digital video image capturing and buffering subsystem for capturing and buffering said frames of digital video image data during said object illumination and video-imaging operations;

a digital video image processing subsystem, disposed in said housing, for processing said frames of digital video image data and reading one or more 1D and/or 2D code symbols graphically represented in said frames of digital video image data, and producing symbol character data representative of said read one or more 1D and/or 2D code symbols;

an input/output subsystem, disposed in said housing, for transmitting said symbol character data to an external host system or other information receiving or responding device; and

a system control subsystem, disposed in said housing, and responsive to said trigger signal, for controlling and/or coordinating the operation of said subsystems above.

2. The automatically-triggered digital video-imaging based code symbol reading system of claim 1, wherein said automatic object presence detection subsystem comprises an IR-based object detection subsystem.

3. The automatically-triggered digital video-imaging based code symbol reading system of claim 2, wherein said IR-based object detection subsystem further comprises an IR-based light emitting diode (LED) and an IR-based photo-receiving diode.

4. The automatically-triggered digital video-imaging based code symbol reading system of claim 1, wherein said area-type image detection array comprises a 2D CMOS image detection array.

5. The automatically-triggered digital video-imaging based code symbol reading system of claim 1, which further comprises:

an automatic exposure measurement subsystem, disposed in said housing, for measuring the intensity of illumination reflected and/or scattered off the illuminated object during object illumination and video-imaging operations, and producing an electrical signal representative of said measured intensity; and

wherein said circuitry in said automatic illumination control subsystem provides drive signals to said illumination array, in response to said electrical signal produced by said automatic exposure measurement subsystem.

6. The automatically-triggered digital video-imaging based code symbol reading system of claim 1, wherein each said code symbol is a bar code symbol selected from the group consisting of a 1D bar code symbol, a 2D bar code symbol, and a data matrix type code symbol structure.

7. The automatically-triggered digital video-imaging based code symbol reading system of claim 1, wherein said image formation optics comprises a lens barrel assembly for supporting a plurality of lenses.

8. The automatically-triggered digital video-imaging based code symbol reading system of claim 1, wherein said field of illumination comprises narrow-band illumination produced from said illumination array.

9. The automatically-triggered digital video-imaging based code symbol reading system of claim 11, wherein said narrow-band illumination is visible to the human vision system.

10. The automatically-triggered digital video-imaging based code symbol reading system of claim 1, wherein said illumination array comprises a plurality of light emitting diodes (LEDs).

11. The automatically-triggered digital video-imaging based code symbol reading system of claim 1, which further comprises a computing platform, disposed in said housing, for implementing said digital video image processing subsystem, said input/output subsystem and said system control subsystem.

12. The automatically-triggered digital video-imaging based code symbol reading system of claim 1, wherein housing is supportable on a countertop surface at a point-of-sale (POS) station or other work environment.

13. The automatically-triggered digital video-imaging based code symbol reading system of claim 1, wherein said housing is also hand-supportable.

14. The automatically-triggered digital video-imaging based code symbol reading system of claim 1, wherein said housing is hand-supportable for enabling hand-supportable digital video-imaging of objects.

15. The automatically-triggered digital video-imaging based code symbol reading system of claim 1, wherein said housing is supportable upon a counter top surface for enabling presentation-type digital video-imaging objects.

16. An automatically-triggered digital video-imaging based code symbol reading system for reading code symbols on objects presented at point of sale (POS) environments, comprising:

a housing having an imaging window;

a digital image formation and detection subsystem, disposed in said housing, and having (i) image formation optics for projecting a field of view (FOV) from an area-type image detection array, through said imaging window and upon an object to be imaged during object illumination and video-imaging operations, and (ii) said area-type image detection array for detecting frames of digital video image data of the object during said object illumination and video-imaging operations;

an illumination subsystem, disposed in said housing, having an illumination array for producing a field of illumination in said FOV during said object illumination and video-imaging operations;

said illumination subsystem including (i) an illumination board supported within said housing and having a central aperture through which said FOV passes during object illumination and video-imaging operations, and on which said illumination array is mounted, and (ii) an assembly of lenses, supported on said illumination board, for focusing and/or shaping illumination emanating from said illumination array so as to produce said field of illumination within said FOV;

wherein said a central aperture in said illumination board is spatially aligned with said imaging window in said housing;

an automatic object detection subsystem, disposed in said housing, for automatically detecting the presence of the object in said FOV, and in response thereto, generating a trigger signal indicative of a triggering event;

an automatic illumination control subsystem, disposed in said housing, for controlling illumination produced from said illumination array during said object illumination and video-imaging operations;

a digital video image capturing and buffering subsystem for capturing and buffering said frames of digital video image data during said object illumination and video-imaging operations;

a digital video image processing subsystem, disposed in said housing, for processing said frames of digital video image data and reading one or more 1D and/or 2D code symbols graphically represented in said frames of digital video image data, and producing symbol character data representative of said read one or more 1D and/or 2D code symbols;

an input/output subsystem, disposed in said housing, for transmitting said symbol character data to an external host system or other information receiving or responding device;

a system control subsystem, disposed in said housing, and responsive to said trigger signal, for controlling and/or coordinating the operation of said subsystems above;

a computing platform, disposed in said housing, and operably connected to said illumination board, for implementing said digital video image processing subsystem, said input/output subsystem and said system control subsystem;

wherein said computing platform includes

(i) a multi-tier modular software architecture characterized by an Operating System (OS) layer, and an Application layer; and

(ii) a microprocessor for running one or more applications stored in one or more software libraries maintained in said Application layer, and

wherein said one or more software libraries contains code associated with a digital video capturing and processing application which is responsive to the generation of said triggering signal.

17. The automatically-triggered digital video-imaging based code symbol reading system of claim 16, wherein said multi-tier modular software architecture further comprises a System CORE (SCORE) layer positioned between said OS layer and said Application layer.

18. The automatically-triggered digital video-imaging based code symbol reading system of claim 16, wherein said OS layer comprises one or more software modules selected from the group consisting of an OS kernel module, an OS file system module, and device driver modules.

19. The automatically-triggered digital video-imaging based code symbol reading system of claim 17, wherein said SCORE layer includes one or more of software modules selected from the group consisting of a tasks manager module, an events dispatcher module, an input/output manager module, a user commands manager module, the timer subsystem module, an input/output subsystem module and an memory control subsystem module.

20. The automatically-triggered digital video-imaging based code symbol reading system of claim 16, wherein said Application layer includes one or more software modules selected from the group consisting of a code symbol decoding module, a function programming module, an application events manager module, a user commands table module, and a command handler module.

21. The automatically-triggered digital video-imaging based code symbol reading system of claim 16, wherein said automatic object presence detection subsystem comprises an IR-based object detection subsystem.

22. The automatically-triggered digital video-imaging based code symbol reading system of claim 21, wherein said IR-based object detection subsystem further comprises an IR-based light emitting diode (LED) and an IR-based photo-receiving diode.

23. The automatically-triggered digital video-imaging based code symbol reading system of claim 22, wherein said area-type image detection array comprises a 2D CMOS image detection array.

24. The automatically-triggered digital video-imaging based code symbol reading system of claim 16, wherein each said code symbol is a bar code symbol selected from the group consisting of a 1D bar code symbol, a 2D bar code symbol, and a data matrix type code symbol structure.

25. The automatically-triggered digital video-imaging based code symbol reading system of claim 16, wherein said field of illumination comprises narrow-band illumination produced from said illumination array.

26. The automatically-triggered digital video-imaging based code symbol reading system of claim 25, wherein said narrow-band illumination is visible to the human vision system.

27. The automatically-triggered digital video-imaging based code symbol reading system of claim 16, wherein said illumination array comprises a plurality of light emitting diodes (LEDs).

28. The automatically-triggered digital video-imaging based code symbol reading system of claim 16, wherein said housing is hand-supportable for enabling hand-supportable digital video-imaging of objects.

29. The automatically-triggered digital video-imaging based code symbol reading system of claim 16, wherein said housing is supportable upon a counter top surface for enabling presentation-type digital video-imaging objects.