Devices and methods of reading monochromatic patterns

• US 8,682,066 B2
• Filed: 03/10/2011
• Issued: 03/25/2014
• Est. Priority Date: 03/11/2010
• Status: Active Grant

• Current Assignee: Ramot at Tel Aviv University Limited (Tel Aviv University)
• Original Assignee: Ramot at Tel Aviv University Limited (Tel Aviv University)
• Inventors: Marom, Emanuel, Konforti, Naim, Golub, Michael, Milgrom, Benjamin
• Primary Examiner(s): Li, Ruiping
• Application Number:
  US13/044,579
• Publication Number:
  US 20110222763A1
• Time in Patent Office: 1,111 Days
• Field of Search: 382/165, 382/190, 359/738, 359/569, 235/462.04, 235/469
• US Class Current: 382/165
• CPC Class Codes: G06K 7/10722 Photodetector array or CCD scanning
• CPC Class Codes: G06K 7/12 using a selected wavelength, e.g. to sense red marks and ignore blue marks
• CPC Class Codes: G06K 7/1491 the method including a reconstruction step, e.g. stitching two pieces of bar code together to derive the full bar code

Abstract

A method of extracting data from an identifiable monochromatic pattern. The method comprises separating a polychromatic optical signal, received from an object having identifiable monochromatic pattern, into a plurality of wavelength components, separately capturing each of the wavelength components, reconstructing a plurality of images each from a different wavelength component, detecting the identifiable monochromatic pattern in one or more of the images, and extracting data associated with or encoded by the detected identifiable monochromatic pattern. The images have different depths of field.

Claims

1. A method of extracting data from an identifiable monochromatic pattern, said method comprising:

using a optical assembly having a mask with a at least concentric ring for separating a polychromatic optical signal, received from an object having identifiable monochromatic pattern, into a plurality of wavelength components;

using an image sensor having a plurality of color channels for separately capturing each of said plurality of wavelength components in another color channel of said plurality of color channels;

reconstructing a plurality of images each from a different color channel of said plurality of color channels that includes a different wavelength component of said plurality of wavelength components;

detecting said identifiable monochromatic pattern in at least one of said plurality of images; and

extracting data associated with or encoded by said detected identifiable monochromatic pattern;

wherein each of said plurality of images has a different depth of field;

wherein said mask and said image sensor are aligned along a common axis.

2. The method of claim 1, wherein said identifiable monochromatic pattern comprises a monochromatic representation of said data.

3. The method of claim 1, wherein said identifiable monochromatic pattern comprises at least one of a contour and an outline of a human face.

4. The method of claim 1, wherein said identifiable monochromatic pattern comprises at least one of a contour and an outline of an article.

5. The method of claim 1, wherein each of said plurality of images having a depth of field which overlaps with another depth of field of another said image.

6. The method of claim 1, wherein said separating is performed so that a defocusing parameter of each image reconstructed from said wavelength component corresponds to a different distance from a reference nominal point.

7. The method of claim 1, wherein said separating is performed so that each of said plurality of wavelength components is set to reconstruct an image having a defocusing parameter between 3 radians and 6 radians.

8. The method of claim 1, wherein said plurality of wavelength components are red, green, and blue color bands.

9. The method of claim 1, wherein said plurality of wavelength components comprises at least one of infrared band and ultraviolet band.

10. The method of claim 1, wherein said detecting comprises identifying the presence or absence of said identifiable monochromatic pattern in each of said plurality of images.

11. The method of claim 10, wherein said identifying is performed according to barcode encoding symbology.

12. The method of claim 10, wherein said identifying is performed according location information indicative of the location of said identifiable monochromatic pattern.

15. The method of claim 1, wherein said image sensor is an active pixel image sensor converting said plurality of wavelength components to three separated color channels, each of said plurality of images is reconstructed from another of said plurality of wavelength components.

16. The method of claim 1, wherein said plurality of color channels are organized in the form of a Bayer Matrix.

17. The method of claim 1, wherein said image sensor captures said plurality of wavelength components at the same time.

18. The method of claim 1, wherein said at least concentric ring each having a different radius.

19. The method of claim 1, wherein said optical assembly is chromatically corrected.

13. A method of analyzing a plurality of color channels of an image sensor, said method comprising:

receiving, at each of a plurality of color channels of an image sensor, another wavelength component signal of a plurality of wavelength component signals which are optically separated from a polychromatic optical signal received from an object having an identifiable monochromatic pattern by a mask with a at least concentric ring of an optical assembly;

reconstructing a plurality of images each from a different of said plurality of color channels;

detecting said identifiable monochromatic pattern in at least one of said plurality of images; and

extracting data associated with or encoded by said detected identifiable monochromatic pattern;

wherein each of said plurality of images has a different depth of field;

wherein said mask and said image sensor are aligned along a common axis.

14. The method of claim 13, wherein said image sensor is a red, green and blue (RGB) image sensor and said plurality of color channels are red, green and blue color channels.