Devices and methods employing dual target auto exposure

• US 8,646,692 B2
• Filed: 09/30/2011
• Issued: 02/11/2014
• Est. Priority Date: 09/30/2011
• Status: Active Grant

• Current Assignee: Hand Held Products Incorporated (Honeywell International Inc.)
• Original Assignee: Hand Held Products Incorporated (Honeywell International Inc.)
• Inventors: Meier, Timothy P., Deloge, Stephen P.
• Primary Examiner(s): Mai, Thien T
• Assistant Examiner(s): LY, TOAN C
• Application Number:
  US13/250,282
• Publication Number:
  US 20130082109A1
• Time in Patent Office: 865 Days
• Field of Search: 235/462.41, 235/462.06, 235/462.11, 235/462.42
• US Class Current: 235/462.41
• 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 7/10792 Special measures in relation to the object to be scanned
• CPC Class Codes: G06K 7/1465 using several successive scans of the optical code

Abstract

The method includes automatically adjusting a first control parameter in a device for capturing a first plurality of images, automatically adjusting a second control parameter in the device for capturing a second plurality of images such that automatic adjustment of the first control parameter is interspersed with, separate from, and obtained generally concurrently with the automatic adjustment of the second control parameter. The adjustment of the first control parameter being determined differently compared to adjustment of the second control parameter. The method may include attempting to decode a decodable indicia utilizing one or more images of the first and second plurality of images.

Claims

1. A device for obtaining images, said device comprising:

an imaging subsystem comprising an image sensor array and an imaging assembly operative for focusing an image onto said image sensor array;

a housing incorporating said imaging subsystem;

wherein said device is configured to acquire a first plurality of images based on a first control parameter in which said first control parameter for a subsequent image of said first plurality of images is adjusted based on a prior image of said first plurality of images, configured to acquire a second plurality of images based on a second control parameter different from said first control parameter in which said second control parameter for a subsequent image of said second plurality of images is adjusted based on a prior image of said second plurality of images, and configured to acquire said first adjusted plurality of images interspersed with said second differently adjusted plurality of images.

2. The device of claim 1 further comprising said device being operable to attempt to decode a decodable indicia utilizing one or more images of said first and second plurality of images.

3. The device of claim 1 further comprising an illumination subsystem operative for projecting an illumination pattern operable for use in acquiring said first plurality of images and said second plurality of images.

4. The device of claim 1 wherein said first plurality of images and said second plurality of images being evenly interspersed so that said first control parameter obtained at image N is utilized in image N+2, and so that said second control parameter obtained at image N+1 is utilized in image N+3.

5. The device of claim 1 wherein said first control parameter and said second control parameter comprises the same control parameter having different values.

6. The device of claim 1 wherein said first control parameter comprises a first exposure control parameter, and said second control parameter comprises a second exposure control parameter.

7. The device of claim 1 wherein said device is operable to determine quality evaluation based on quality of pixel data of at least one of said images of said first plurality of images and said second plurality of images.

8. The device of claim 7 further comprising said device being operable to attempt to decode a decodable indicia from selected images based on said quality evaluation.

9. The device of claim 1 wherein said device is operable to attempt to decode the decodable indicia comprising a bar code.

10. The device of claim 1 wherein said device is operable to attempt to decode a decodable indicia comprising at least one of a bar code disposed on a substrate, and a bar code disposed on a backlit display.

11. The device of claim 1 wherein said device comprises a hand held indicia reading terminal.

12. An indicia reading terminal comprising:

an illumination subsystem operative for projecting an illumination pattern;

an imaging subsystem comprising an image sensor array and an imaging assembly operative for focusing an image onto said image sensor array;

a housing incorporating said illumination subsystem and said imaging subsystem;

wherein said indicia reading terminal is configured to acquire a first plurality of images exposed during illuminated portions of said illumination pattern based on a first control parameter in which said first control parameter for a subsequent image of said first plurality of images is adjusted based on a prior image of said first plurality of images, configured to acquire a second plurality of images exposed during unilluminated portions of said illumination pattern based on a second control parameter different from said first control parameter in which said second control parameter for a subsequent image of said second plurality of images is adjusted based on a prior image of said second plurality of images, and configured to obtain said first adjusted plurality of images interspersed with said second differently adjusted plurality of images; and

wherein said indicia reading terminal is operable to attempt to decode a decodable indicia comprising a bar code disposed on a substrate using at least one of said first plurality of images, and operable to attempt to decode a decodable indicia comprising a bar code disposed on a backlit display using at least one of said second plurality of images.

13. The indicia reading terminal of claim 12 wherein said first plurality of images and said second plurality of images being evenly interspersed so that a first control parameter obtained at image N is utilized in image N+2, and so that a second control parameter obtained at image N+1 is utilized in image N+3.

14. The indicia reading terminal of claim 12 wherein said first image control parameter and said second image control parameter comprises the same image control parameter having different values.

15. The indicia reading terminal of claim 12 wherein said first control parameter comprises a first exposure control parameter, and said second control parameter comprises a second exposure control parameter.

16. The indicia reading terminal of claim 12 wherein said indicia reading terminal is operable to determine quality evaluation of at least one of said images of said first plurality of images and said second plurality of images, and wherein said indicia reading terminal being operable to attempt to decode the decodable indicia comprises said indicia reading terminal being operable to attempt to decode a decodable indicia from selected images based on said quality evaluation.

17. The indicia reading terminal of claim 12 wherein said indicia reading terminal comprises a hand held indicia reading terminal.

18. A method for use in obtaining images, the method comprising:

automatically adjusting a first control parameter in a device for capturing a first plurality of images;

automatically adjusting a second control parameter different from the first control parameter in the device for capturing a second plurality of images; and

automatically obtaining the first adjusted plurality of images interspersed with the second differently adjusted plurality of images.

19. The method of claim 18 further comprising attempting to decode the decodable indicia utilizing one or more images of the first and second plurality of images.

20. The method of claim 18 further comprising providing an illumination pattern operable for use in acquiring said first plurality of images and said second plurality of images.

21. The method of claim 18 wherein the first plurality of images and the second plurality of images being evenly interspersed so that a first control parameter obtained at image N is utilized in image N+2, and so that a second control parameter obtained at image N+1 is utilized in image N+3.

22. The method of claim 18 wherein the first control parameter and the second control parameter comprises the same control parameter having different values.

23. The method of claim 18 wherein said first control parameter comprises a first exposure control parameter, and said second control parameter comprises a second exposure control parameter.

24. The method of claim 18 wherein the first plurality of images is configured to decoding decodable indicia disposed on a substrate, and the second plurality of images is adapted to decoding decodable indicia disposed on a backlit display.

25. The method of claim 18 further comprising determining a quality evaluation of at least one of the images of the first plurality of images and the second plurality of images, and further comprising attempting to decode decodable indicia utilizing one or more images selected from images based on the quality evaluation.

26. The method of claim 18 wherein the decodable indicia comprising a bar code.

27. A method for decoding decodable indicia, the method comprising:

projecting an illumination pattern from an indicia reading terminal onto a decodable indicia;

automatically adjusting a first control parameter in the indicia reading terminal for capturing a first plurality of images exposed during illuminated portions of the illumination pattern;

automatically adjusting a second control parameter different from the first control parameter in the indicia reading terminal for capturing a second plurality of images exposed during unilluminated portions of the illumination pattern;

automatically obtaining the first adjusted plurality of images interspersed with the second differently adjusted plurality of images; and

attempting to decode the decodable indicia utilizing one or more images of the first and second plurality of images.

28. The method of claim 27 wherein the first plurality of images and the second plurality of images being evenly interspersed so that a first control parameter obtained at image N is utilized in image N+2, and so that a second control parameter obtained at image N+1 is utilized in image N+3.

29. The method of claim 27 further comprising optimizing the control parameter for images exposed during the illuminated portions of the illumination pattern for decoding the decodable indicia disposed on a substrate, and optimizing the control parameter for the images exposed during unilluminated portions of the illumination pattern for decoding the decodable indicia disposed on a backlit display.

30. The method of claim 27 wherein the first image control parameter and the second image control parameter comprises the same image control parameter having different values.

31. The method of claim 27 wherein said first control parameter comprises a first exposure control parameter, and said second control parameter comprises a second exposure control parameter.

32. The method of claim 27 further comprising determining a quality evaluation of at least one of the images of the first plurality of images and the second plurality of images, and wherein the attempting to decode comprises attempting to decode decodable indicia utilizing one or more images selected from images based on the quality evaluation.