Method of illuminating objects on a countertop surface using an automatically-triggered digital image capture and processing system which maintains illumination rays substantially within the field of view (FOV) of said system, above which the field of view (FOV) of human operator and spectating customers are positioned

• US 20080283608A1
• Filed: 01/31/2008
• Published: 11/20/2008
• 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: Veksland, Michael, Ren, Jie, Knowles, C. Harry, Au, Ka Man, Giordano, Patrick, Yan, Weizhen, Smith, Taylor, Mandal, Sudhin, Kotlarsky, Anatoly, Miraglia, Michael V., Foney, Shawn De, Wilz, David M. SR., Zhu, Xiaoxun, Allen, Christopher
• Granted Patent: US 8,052,057 B2
• Time in Patent Office: Days
• US Class Current: 235/462.07
• CPC Class Codes: G06K 7/10722 Photodetector array or CCD scanning
• CPC Class Codes: G06K 7/10732 Light sources
• CPC Class Codes: G06K 7/10752 Exposure time control
• CPC Class Codes: G06K 7/10821 further details of bar or optical code scanning devices
• CPC Class Codes: G06K 7/109 adaptations to make the hand-held scanner useable as a fixed scanner

Abstract

A method of illuminating objects on a countertop surface using an automatically-triggered digital image capture and processing system having a single array of LEDs disposed near and behind the upper edge portion of its imaging window, which is provided with an illumination-focusing lens structure integrated therein. During object detection, illumination and imaging operations on the countertop surface, typically at a retail point of sale (POS) station, visible illumination generated by the LEDs is focused and projected by the illumination-focusing lens structure so that the system maintains its illumination rays substantially within the field of view (FOV) of said system, and above which the field of view (FOV) of human operator and spectators are positioned, so that the field of illumination extends substantially across the working distance of the FOV of the system, and in a way to illuminate objects located anywhere within the working distance of said system, while minimizing annoyance to the system operator, as well as others in the vicinity thereof during system operation.

Claims

1. A method of illuminating objects on a countertop surface using an automatically-triggered digital image capture and processing system which maintains illumination rays substantially within the field of view (FOV) of said system, and above which the field of view (FOV) of human operator and spectators are positioned, said method comprising the steps of:

(a) supporting an automatically-triggered digital image capture and processing system upon a countertop surface of a point of sale (POS) environment where a human operator and customers happen to be present during object illumination and imaging operations, wherein said automatically-triggered digital image capture and processing system includes

(1) a housing having an imaging window with an illumination-focusing lens structure integrated within said imaging window,

(2) an image formation and detection subsystem, disposed in said housing, and having image formation optics for projecting a field of view (FOV) through said imaging window and onto an area-type image detection array, for forming and detecting 2D digital images of an object in said FOV, during object illumination and imaging operations,

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

(4) an illumination subsystem, disposed in said housing, having a single array of LEDs, disposed immediately behind said illumination-focusing lens structure, for generating a field of visible illumination that reflects off an object within said FOV and is transmitted back through said imaging window and onto said area-type image detection array to form one or more 2D digital images of said object,

(5) an image capturing and buffering subsystem, disposed in said housing, for capturing and buffering 2D digital images detected by said image formation and detection subsystem,

(6) a digital image processing subsystem, disposed in said housing, for processing 2D digital images captured and buffered by said image capturing and buffering subsystem and reading one or more 1D and/or 2D code symbols graphically represented therein, and generating symbol character data representative of said read 1D and/or 2D code symbols, and

(7) a system control subsystem, disposed in said housing and responsive to said trigger event signal, for controlling and/or coordinating one or more said subsystems during object illumination and imaging operations so that an object present in said FOV will be automatically illuminated and imaged by said system;

(b) adjusting said housing relative to said countertop surface so that said field of visible illumination generated from said single array of LEDs, is confined below the field of view of the system operator and customers who happen to be present during object illumination and imaging operations; and

(c) presenting an object bearing a code symbol, within said FOV so that (i) said automatic object detection subsystem automatically detects said object and generates said trigger event signal, (ii) said illumination subsystem automatically illuminates said object within said FOV, (iii) said image formation and detection subsystem automatically forms and detects one or more 2D digital images of the illuminated object, (iv) said image capturing and buffering subsystem automatically captures and buffers the 2D digital images, and (v) said digital image processing subsystem automatically processes said buffered 2D digital images in an attempt to read one or more 1D and/or 2D code symbols graphically represented therein and generate symbol character data representative of code symbols read.

2. The method of claim 1, wherein during step (a), said image formation and detection subsystem has a periodic snap shot mode of the operation supporting periodic generation of snap-shot type image acquisition cycles during object illumination and imaging operations carried out during step (c).

3. The method of claim 1, wherein during step (a), said image formation and detection subsystem has a single snap-shot mode of the operation supporting a single snap-shot image acquisition cycle during object illumination and imaging operations carried out during step (c).

4. The method of claim 1, wherein during step (a), said image formation and detection subsystem has a real video mode of the operation supporting a video image acquisition cycle during object illumination and imaging operations carried out during step (c).

5. The method of claim 1, wherein during step (a), said single array of LEDs is disposed near and behind the upper edge portion of said imaging window, so as to focus and project visible illumination from said LEDs, which extends substantially across the working distance of the FOV of the system, and in a way to illuminate objects located within the working distance of said system, while minimizing annoyance to the system operator, as well as others in the vicinity thereof during system operation.

6. The method of claim 1, wherein said illumination-focusing lens structure is made from an optically transparent material light refractive material.

7. The method of claim 1, wherein during step (a), said automatically-triggered digital image capture and processing system further comprises an input/output subsystem, disposed in said housing, for outputting processed image data, including symbol character data, to an external host system or other information receiving or responding device.

8. The method of claim 1, wherein during step (a), said automatically-triggered digital image capture and processing system further comprises an object targeting illumination subsystem, disposed in said housing, for generating and projecting a targeting illumination beam within a portion of said FOV, in response to the generation of an object detection event signal.

9. The method of claim 8, wherein said targeting illumination beam is momentarily switched off while said array of LEDs is producing said field of illumination within said FOV and said area-type image detection array is detecting each 2D digital image frame of said detected object within said FOV, during object illumination and imaging operations.

10. The method of claim 1, wherein said 1D and/or 2D code symbols are selected from the group of 1D and/or 2D bar code symbols, PDF symbols and data matrix symbols.

11. The method of claim 1, wherein said linear array of LEDs comprise a linear array of visible LEDs.

12. The method of claim 1, wherein said an illumination-focusing lens structure is made from an optically transparent material light refractive material.