Apparatus for and method of reading printed and electronic codes

• US 8,590,792 B2
• Filed: 09/14/2011
• Issued: 11/26/2013
• Est. Priority Date: 09/14/2011
• Status: Active Grant

• Current Assignee: Symbol Technologies, LLC (Zebra Technologies Corporation)
• Original Assignee: Symbol Technologies, Inc. (Zebra Technologies Corporation)
• Inventors: Tan, Chinh, Barkan, Edward, Drzymala, Mark
• Primary Examiner(s): WALSH, DANIEL I
• Application Number:
  US13/232,361
• Publication Number:
  US 20130062412A1
• Time in Patent Office: 804 Days
• Field of Search: 235/462.01, 235/454, 235/455, 235/462.25, 235/462.3, 235/462.31, 235/462.42
• US Class Current: 235/455
• CPC Class Codes: G06K 7/10752 Exposure time control
• CPC Class Codes: G06K 7/1095 the scanner comprising adaptations for scanning a record carrier that is displayed on a display-screen or the like

Abstract

An apparatus for, and method of, imaging printed and electronic codes associated with transactions or objects to be processed, support a window on a housing, illuminate the codes through the window with illumination light from an energizable illumination system, capture return illumination light from the illuminated codes through the window with an array of light sensors looking at a field of view of a solid-state, exposable imager, and process the captured return illumination light. A printed code is read by exposing the imager for a first exposure time and by also energizing the illumination system during the first exposure time. An electronic code is read by exposing the imager for a second exposure time that is longer than the first exposure time and by also deenergizing the illumination system during the second exposure time.

Claims

1. An apparatus operative for reading printed and electronically displayed codes on an object, comprising:

a housing;

a window supported by the housing;

an energizable illumination system supported by the housing and operative for illuminating the object with illumination light directed through the window;

a solid-state, exposable imager supported by the housing and having an array of light sensors looking at a field of view that extends through the window, the array of light sensors operative for capturing light from the object;

a mode changing system supported by the housing and including an object sensing system for detecting how long an object has been positioned in an object field of view in order to determine presence of an electronically displayed code, wherein the object sensing system includes an object light source operative for emitting object sensing IR light and an object light sensor operative for detecting return object sensing IR light returned from the object over the object field of view;

a controller operatively connected to the imager and the illumination system and operative for processing the captured light from the object, the controller being operative for exposing the imager for a first exposure time and by also energizing the illumination system during the first exposure time while in a first code reading mode, and operative for exposing the imager for at least a second exposure time that is longer than the first exposure time and by also de-energizing the illumination system during the at least second exposure time while in a second code reading mode; and

the mode changing system further being (1) operative for directing the controller to operate in the first code reading mode in response to the object sensing system detecting the presence of the object and (2) operative for directing the controller to change from the first code reading mode to the second code reading mode when the object has been in the object field of view for a duration exceeding a pre-determined duration and without a barcode being successfully decoded by the controller when operating in the first code reading mode.

2. The apparatus of claim 1, wherein the controller cyclically exposes the imager in a sequence of different exposure times, the sequence having at least one first exposure time and at least one second exposure time.

3. The apparatus of claim 1, wherein the controller operates the imager at an adjustable frame rate of multiple frames per second, and wherein the first exposure time lasts for a fraction of one frame.

4. The apparatus of claim 1, wherein the controller operates by default in a printed code reading mode of operation in which the imager is repeatedly exposed for successive first exposure times;

and further wherein the controller, in response to detection of the electronically displayed code by the mode changing system, changes from the printed code reading mode of operation to an electronically displayed code reading mode of operation in which the imager is exposed for at least one second exposure time.

5. The apparatus of claim 4, wherein the object has a display screen on which the electronically displayed code is displayed.

6. The apparatus of claim 4, wherein the mode changing system is operative for detecting a hot spot in the field of view, and for alerting the controller of the presence of the electronically displayed code when the hot spot has been detected.

7. The apparatus of claim 6, wherein the electronically displayed code is displayed on a display screen, and wherein at least a portion of the illumination light is incident on the display screen for reflection therefrom as the hot spot.

8. The apparatus of claim 1, wherein the window is substantially planar, and wherein the housing supports the window in one of a generally upright and a generally horizontal plane.

9. The apparatus of claim 1, and further comprising another window supported by the housing;

wherein each window is substantially planar; and

wherein the housing supports one of the windows in a substantially upright plane, and supports the other of the windows in a generally horizontal plane that intersects the upright plane.

10. A method of reading printed and electronically displayed codes on an object, with an electro-optical reading workstation, comprising:

detecting presence of an object in an object field of view with an object sensing system and detecting how long the object has been positioned in the object field of view, wherein the object sensing system includes an object light source operative for emitting object sensing IR light and an object light sensor operative for detecting return object sensing IR light returned from the object over the object field of view;

in response to the object sensing system detecting the presence of the object, operating the electro-optical reading workstation in a default mode by exposing an imager for a first exposure time and by also energizing the illumination system during the first exposure time;

determining presence the object that has been in the object field of view for a duration exceeding a predetermined duration; and

when the object has been placed in the object field of view for a duration exceeding the predetermined duration and without a barcode being successfully decoded when operating in the default mode, operating the electro-optical reading workstation in another mode by exposing the imager for at least a second exposure time and by also de-energizing the illumination system during the at least one second exposure time, and wherein the second exposure time is longer than the first exposure time.

11. The method of claim 10, wherein the exposing is performed cyclically by exposing the imager in a sequence of different exposure times, the sequence having at least one first exposure time and at least one second exposure time.

12. The method of claim 10, wherein the imager operates at an adjustable frame rate of multiple frames per second, and wherein the first exposure time lasts for a fraction of one frame.

13. The method of claim 10, wherein the printed codes are read by default in a printed code reading mode of operation in which the imager is repeatedly exposed for successive first exposure times and the illumination system is energized for each first exposure time;

and further comprising changing from the printed code reading mode of operation to an electronic code reading mode of operation in which the imager is exposed for at least one second exposure time, by detecting the presence of the electronically displayed code in the field of view and by de-energizing the illumination system for the at least second exposure time.

14. The method of claim 10, wherein the object has a display screen on which the electronically displayed code is displayed.

15. The method of claim 13, wherein the changing is performed by detecting a hot spot in the field of view, and by indicating the presence of the electronically displayed code when the hot spot has been detected.

16. The method of claim 15, and displaying the electronically displayed code on a display screen, and wherein at least a portion of the illumination light is incident on the display screen for reflection therefrom as the hot spot.

17. The method of claim 10, wherein the electro-optical workstation comprises a window, supported by a housing, that is substantially planar, and further wherein the housing supports the window in one of a generally upright plane and a generally horizontal plane.

18. The method of claim 17, wherein the electro-optical workstation further comprises another window supported by the housing, wherein each window is substantially planar, and wherein the housing supports one of the windows in a substantially upright plane, and supports the other of the windows in a generally horizontal plane that intersects the upright plane.