Method of and system for reading visible and/or invisible code symbols in a user-transparent manner using visible/invisible illumination source switching during data capture and processing operations

• US 8,408,468 B2
• Filed: 12/13/2010
• Issued: 04/02/2013
• Est. Priority Date: 12/13/2010
• Status: Active Grant

• Current Assignee: Metrologic Instruments Incorporated (Honeywell International Inc.)
• Original Assignee: Metrologic Instruments Incorporated (Honeywell International Inc.)
• Inventors: Kearney, Sean Philip, Van Horn, Erik
• Primary Examiner(s): Le, Thien M
• Assistant Examiner(s): TAYLOR, APRIL ALICIA
• Application Number:
  US12/966,256
• Publication Number:
  US 20120145788A1
• Time in Patent Office: 841 Days
• Field of Search: 235/462.01, 235/462.09, 235/462.25, 235/462.31, 235/462.32, 23546241-46245, 235/462.48, 235/472.01, 235/462.07
• US Class Current: 235/462.25
• CPC Class Codes: G06K 2207/1011 Aiming
• CPC Class Codes: G06K 2207/1012 Special detection of object
• CPC Class Codes: G06K 2207/1018 Source control
• CPC Class Codes: G06K 7/0004 Hybrid readers
• CPC Class Codes: G06K 7/10574 Multiple sources
• CPC Class Codes: G06K 7/10584 Source control
• CPC Class Codes: G06K 7/10732 Light sources
• CPC Class Codes: G06K 7/10821 further details of bar or optical code scanning devices
• CPC Class Codes: G06K 7/12 using a selected wavelength, e.g. to sense red marks and ignore blue marks
• CPC Class Codes: G06K 7/1404 Methods for optical code recognition

Abstract

Method of and system for reading visible and/or invisible code symbols in a user-transparent manner using visible/invisible illumination switching during data capture and processing operations.

Claims

1. A digital-imaging code symbol reading system comprising:

a hand-supportable housing having alight transmission aperture;

an image formation and detection subsystem, disposed in said hand-supportable housing, having image formation optics for producing, and projecting a field of view (FOV) through said light transmission aperture and onto an area-type image detection array for detecting one or more digital images of an object within said FOV supporting one or more visible and/or visible code symbols, during object illumination and imaging operations;

a multi-mode illumination subsystem, disposed in said hand-supportable housing, said multi-mode illumination subsystem includes;

(i) a visible illumination array for producing a field of visible illumination within said FOV, and illuminating a visible code symbol on said object detected in said FOV, so that said illumination reflects off said object and is transmitted back through said light transmission aperture and onto said image detection array to form said digital image of said visible code symbol, and

(ii) an invisible illumination array for producing a field of invisible illumination within said FOV, and illuminating an invisible code symbol on said object detected in said FOV, so that said illumination reflects off said object and is transmitted back through said light transmission aperture and onto said image detection array to form said digital image of said invisible code symbol;

an image capturing and buffering subsystem, disposed in said hand-supportable housing, for capturing and buffering digital images of visible and/or invisible code symbols detected by said image formation and detection subsystem;

a digital image processing subsystem, disposed in said hand-supportable housing, for processing said one or more digital images of visible and/or invisible code symbols captured and buffered by said image capturing and buffering subsystem and reading visible and/or invisible bar code symbols represented in said digital images;

an input/output subsystem, disposed in said hand-supportable housing, for outputting processed image data to an external host system or other information receiving or responding device; and

a system control subsystem, disposed in said hand-supportable housing, and responsive to a triggering event to initiate object illumination and imaging operations within said digital-imaging code symbol reading system, and controlling and/or coordinating said subsystems within said digital-imaging code symbol reading system, during object illumination and imaging operations;

wherein upon detecting said triggering event, said system controller generates a first control signal, and in response thereto, said multi-mode illumination subsystem generates said field of visible illumination within said FOV, and illuminates any visible code symbol on said object detected in said FOV, so that said visible illumination reflects off said visible code symbol and is transmitted back through said light transmission aperture and onto said image detection array to form said digital image of said visible code symbol, and thereafter said digital image is decoded processed by said digital image processing subsystem in effort to read said visible code symbol on said object;

wherein, in the event that said visible code symbol is not read after a predetermined number of illumination, imaging and processing attempts, then said system control subsystem generates a second control signal, said multi-mode illumination subsystem generates said field of invisible illumination within said FOV, and illuminates any invisible code symbol on said object detected in said FOV, so that said invisible illumination reflects off said invisible bar code symbol and is transmitted back through said light, transmission aperture and onto said image detection array to form said digital image of said invisible code symbol, and thereafter said digital image is decoded processed by said digital image processing subsystem in effort to read said invisible bar code symbol on said object; and

wherein, in the event that said invisible code symbol is not read after a predetermined number of illumination, imaging and processing attempts, then said system control subsystem resumes detection of a subsequent triggering event.

2. The digital-imaging code symbol reading system of claim 1, which further comprises an automatic object detection subsystem, disposed in said hand-supportable housing, for automatically detecting the presence of said object within said FOV and generating said triggering event.

3. The digital-imaging code symbol reading system of claim 1, which further comprises a manual trigger switch for generating said triggering event whenever an operator manually actuates said manual trigger switch.

4. The digital-imaging code symbol reading system of claim 1, which further comprises an illumination control subsystem, disposed in said hand-supportable housing, for controlling the operation of said visible and invisible illumination arrays within said multi-mode illumination subsystem.

5. The digital-imaging based code symbol reading system of claim 1, wherein said visible illumination array comprises an array of visible LEDs, and said invisible illumination array comprises an array of invisible LEDs.

6. The digital-imaging code symbol reading system of claim 1, wherein said visible and/or invisible code symbols are symbols selected from the group consisting of 1D bar code symbols, 2D bar code symbols and data-matrix type code symbols.

7. A method of reading code symbols carried out by a digital-imaging based code symbol reading system, comprising the steps of:

(a) bringing in proximity with an object bearing one or more visible and/or invisible code symbols, a digital-imaging based bar code symbol reading system having a hand-supportable housing with a light transmission window and containing (i) an image formation and detection subsystem for forming and detecting digital images of objects within a field of view (FOV) of said image formation and detection subsystem, (ii) an illumination subsystem for generating either a field of visible illumination with said FOV or a field of invisible illumination within said FOV, (iii) a digital image processing subsystem for processing digital images, (iv) an input/output subsystem, and (v) a system control subsystem;

(b) detecting an object in said FOV of said image formation and detection subsystem and generating a triggering event;

(c) in response to the generation of said triggering event, said image formation and detection subsystem detecting and capturing a digital image of an said object in the FOV while being illuminated with said field of visible illumination generated by said illumination subsystem;

(d) said digital image processing subsystem processing said digital image in effort to read said visible bar code symbol graphically represented in said digital image detected in step (c);

(e) in the event that said digital image processing subsystem reads the visible bar code symbol during step (d), then said digital image processing subsystem producing symbol character data representative of said read visible bar code symbol, and said input/output subsystem transmitting said symbol character data to a host system;

(f) in the event that said digital image processing subsystem cannot read said visible bar code symbol during step (d) after one or more attempts at doing so, then said image formation and detection subsystem detects and captures said digital image of said object in the FOV while being illuminated with said field of invisible illumination generated by said illumination subsystem;

(g) said digital image processing subsystem processing said digital image detected in step (e) in effort to read an invisible bar code symbol graphically represented in said digital image detected in step (f);

(h) in the event that said digital image processing subsystem reads said invisible bar code symbol during step (g), then said digital image processing subsystem producing symbol character data representative of said read invisible bar code symbol, and said input/output subsystem transmitting said symbol character data to said host system; and

(i) in the event that said digital image processing subsystem cannot read an invisible bar code symbol during step (g) after one or more attempts at doing so, then said system control subsystem returns control to step (b) and resumes object detection or re-detection operations.

8. The method of claim 7, wherein step (b) comprises generating said triggering event by actuating a manual trigger switch integrated with said hand-supportable housing.

9. The method of claim 7, wherein step (b) comprises generating said triggering event by automatically detecting said object in said FOV using an automatic objection detector disposed in said hand-supportable housing.

10. The method of claim 7, wherein said visible and/or invisible code symbols are symbols selected from the group consisting of 1D bar code symbols, 2D bar code symbols and data-matrix type code symbols.

11. A hand-supportable laser scanning code symbol reading system for reading visible and/or invisible code symbols in a user-transparent manner using visible/invisible illumination switching during scan data detection and processing operations, comprising:

a hand-supportable housing with a light transmission window;

a multi-mode laser scanning module, disposed in said hand-supportable housing, responsive to first and second control signals generated by a system controller, wherein said multi-mode laser scanning module includes;

(i) a laser drive module for driving a visible laser source to produce a visible laser beam in response to receiving said first control signal from said system controller, and for driving an invisible laser source to produce an invisible laser beam in response to receiving said second control signal from said system controller, and

(ii) a laser scanning mechanism for scanning said visible laser beam across a laser scanning field defined external to said light transmission window, and any visible code symbol on an object in said laser scanning field, and for scanning said invisible laser beam across said laser scanning field and any invisible code symbol on said object in said laser scanning field;

light collection optics, disposed in said hand-supportable housing, for collecting light reflected/scattered from scanned object in said laser scanning field;

a photo-detector, disposed in said hand-supportable housing, for detecting the intensity of collected light from said code symbols, and generating an analog scan data signal corresponding to said detected light intensity during laser scanning operations;

an analog scan data signal processor, disposed in said hand-supportable housing, for processing said analog scan data signals and converting the processed analog scan data signals into digitized data signals;

a programmed decode processor, disposed in said hand-supportable housing, for decode processing said digitized data signals, and generating symbol character data representative of each visible code symbol scanned by said visible laser beam and each invisible code symbol scanned by said invisible laser beam; and

an input/output (I/O) communication interface, disposed in said hand-supportable housing, for interfacing with a host system and transmitting symbol character data to said host system, via a wired or wireless communication link, supported by said hand-supportable laser scanning code symbol reading system and said host system; and

said system controller for controlling and/or orchestrating operations within said hand-supportable laser scanning bar code symbol reading system;

wherein when said system controller generates said first control signal, said visible laser source generates said visible laser beam and said laser scanning mechanism scans said visible laser beam across any visible code symbol on said object in said laser scanning field during laser scanning operations, so as to generate said analog scan data signal which is processed and converted into a digitized data signal, which is then decoded processed in effort to read said visible bar code symbol on said object;

wherein, in the event that said visible code symbol is not read after a predetermined number of scanning and decode processing attempts, then said system controller generates said second control signal, said invisible laser source generates said invisible laser beam and said laser scanning mechanism scans said invisible laser beam across any invisible code symbol on said object located in said laser scanning field during laser scanning operations, so as to generate said analog scan data signal which is processed and converted into a digitized data signal, which is then decoded processed in effort to read said invisible bar code symbol on said object; and

wherein, in the event that said invisible code symbol is not read after a predetermined number of scanning and decode processing attempts, then said system controller returns to detecting or re-detecting an object in said laser scanning field.

12. The hand-supportable laser scanning code symbol reading system of claim 11, which further comprises a manual trigger switch for generating a trigger event upon an operator actuating said manual trigger switch.

13. The hand-supportable laser scanning code symbol reading system of claim 11, which further comprises object detection circuit for generating a triggering event when said object is automatically detected in said FOV.

14. The hand-supportable laser scanning code symbol reading system of claim 11, wherein said visible and/or invisible code symbols are symbols selected from the group consisting of 1D bar code symbols, 2D bar code symbols and data-matrix type code symbols.

15. A method of reading visible and/or, invisible code symbols in a user-transparent manner using visible/invisible illumination switching during scan data detection and processing operations, comprising the sequence of steps of:

(a) bringing a hand-supportable laser scanning code symbol reading system in proximity with an object bearing one or more visible and/or invisible code symbols, a said hand-supportable laser scanning code symbol reading system including a hand-supportable housing with a light transmission window and containing components including;

(i) a laser scanning module, disposed in said hand-supportable housing, responsive to first and second control signals generated by a system controller, wherein said laser scanning module includds (1) a laser drive module for driving a visible laser source to produce a visible laser beam in response to receiving said first control signal from said system controller, and for driving an invisible laser source to produce an invisible laser beam in response to receiving said second control signal from said system controller, and (2) a laser scanning mechanism for scanning said visible laser beam across a laser scanning field defined external to said light transmission window, and any visible code symbol on said object in said laser scanning field, and for scanning said invisible laser beam across said laser scanning field and any invisible code symbol on said object in said laser scanning field;

(ii) light collection optics for collecting light reflected/scattered from scanned object in the scanning field, and a photo-detector for detecting the intensity of collected light and generates an analog scan data signal corresponding to the detected light intensity during scanning operations;

(iii) an analog scan data signal processor, disposed in said hand-supportable housing, for processing said analog scan data signals and converting the processed analog scan data signals into digitized data signals;

(iv) a programmed decode processor, disposed in said hand-supportable housing, for decode processing said digitized data signals, and generating symbol character data representative of each visible code symbol scanned by said visible laser beam and each invisible code symbol scanned by said invisible laser beam; and

(v) an I/O communication interface for transmitting symbol character data to a host system;

(b) detecting said object in said laser scanning field and generating a triggering event;

(c) in response to the generation of said triggering event, said visible laser beam source generating said visible laser beam, said laser scanning mechanism repeatedly scanning said visible laser beam across any visible code symbol on the object in said laser scanning field, said light collection optics collecting light reflected/scattered from said scanned visible code symbol in said laser scanning field, said photo-detector automatically detecting the intensity of collected light and generating said analog scan data signal corresponding to the light intensity detected during scanning operations, said analog scan data processor processing said analog scan data signal and converting the processed analog scan data signal into a first digitized data signal;

(d) said decode processor processing said first digitized data signal in effort to read a visible code symbol scanned during step (c);

(e) in the event that said decode processor reads said visible code symbol during step (d), then said decode processor producing symbol character data representative of said visible bar code symbol, and said I/O communication interface transmitting said symbol character data to said host system;

(f) in the event that said decode processor cannot read a visible bar code symbol during step (d) after one or more attempts at doing so, then said invisible laser beam source generating said invisible laser beam, said laser scanning mechanism repeatedly scanning said invisible laser beam across any invisible code symbol on the object in said laser scanning field, said light collection optics collecting light reflected/scattered from said scanned invisible code symbol in said laser scanning field, said photo-detector automatically detecting the intensity of collected light and generating said analog scan data signal corresponding to the light intensity detected during scanning operations, said analog scan data processor processing said analog scan data signal and converting the processed analog scan data signal into a second digitized data signal;

(g) said decode processor processing said second digitized data signal in effort to read an invisible code symbol scanned during step (f);

(h) in the event that said decode processor reads an invisible bar code symbol during step (g), then said decode processor producing symbol character data representative of said invisible bar code symbol, and said I/O communication interface transmitting said symbol character data to said host system; and

(i) in the event that said decoder processor cannot read an invisible bar code symbol during step (g) after one or more attempts at doing so, then said system controller returns control to step (b) and resumes object detection operations.

16. The method of claim 15, wherein step (b) comprises generating said triggering event by actuating a manual trigger switch integrated with said hand-supportable housing.

17. The method of claim 15, wherein step (b) comprises generating said triggering event by automatically detecting said object in said FOV using an automatic objection detector disposed in said hand-supportable housing.

18. The method of claim 15, wherein said visible and/or invisible code symbols are symbols selected from the group consisting of 1D bar code symbols, 2D bar code symbols and data-matrix type code symbols.