MULTISPECTRAL BARCODE IMAGING

• US 20110163163A1
• Filed: 01/06/2011
• Published: 07/07/2011
• Est. Priority Date: 06/01/2004
• Status: Abandoned Application

• Current Assignee: HID Global Corporation (Assa Abloy AB)
• Original Assignee: Lumidigm Incorporated (Assa Abloy AB)
• Inventors: Rowe, Robert K.
• Application Number:
  US12/986,026
• Publication Number:
  US 20110163163A1
• Time in Patent Office: Days
• US Class Current: 235/462.25
• CPC Class Codes: G06V 10/143 Sensing or illuminating at different wavelengths
• CPC Class Codes: G06V 40/1324 by using geometrical optics, e.g. using prisms G06V40/1312 takes precedence
• CPC Class Codes: G06V 40/1394 using acquisition arrangements
• CPC Class Codes: G06V 40/45 Detection of the body part being alive

Abstract

Methods and systems are provided for performing a biometric measurement on an individual. A purported skin site of the individual is illuminated under a plurality of distinct optical conditions during a single illumination session. Light scattered beneath a surface of the purported skin site is received separately for each of the plurality of distinct optical conditions. A multispectral image of the purported skin site is derived from the received light. A biometric function is performed with the derived multispectral image.

Claims

1-28. -28. (canceled)

29. A method of reading a barcode, the method comprising:

illuminating the barcode under a plurality of distinct optical conditions during a single illumination session;

receiving light scattered from the barcode separately for each of the plurality of distinct optical conditions;

deriving a spatiospectral multispectral image from the received light; and

decoding the barcode from the spatiospectral multispectral image.

30. The method recited in claim 29 wherein illuminating the barcode under a plurality of distinct optical conditions comprises illuminating the barcode sequentially under the distinct optical conditions.

31. The method recited in claim 29 wherein the plurality of distinct optical conditions comprise distinct polarization conditions.

32. The method recited M claim 29 wherein the plurality of distinct optical conditions comprise distinct wavelengths of illumination light.

33. The method recited in claim 32 wherein:

illuminating the barcode under a plurality of distinct optical conditions during a single illumination sessions comprises simultaneously illuminating the barcode with illumination at a plurality of distinct wavelengths; and

receiving light scattered from the barcode separately for each of the plurality of distinct optical conditions comprises filtering the scattered light to separate the plurality of distinct wavelengths.

34. The method recited in claim 33 wherein filtering the scattered light comprises filtering the scattered light with a color filter array having a plurality of distributed filter elements, each filter element being adapted to transmit light of one of a limited number of specified narrowband wavelength ranges.

35. The method recited in claim 29 wherein:

illuminating the barcode under a plurality of distinct optical conditions comprises illuminating the barcode with light having a first polarization for each of the distinct optical conditions; and

receiving light scattered from the barcode comprises polarizing the received light with a second polarization,

wherein the first and second polarizations substantially define a cross-polarization condition.

36. The method recited in claim 35 wherein the first and second polarizations are each linear polarizations.

37. The method recited in claim 35 wherein the first and second polarizations are each circular polarizations.

38. The method recited in claim 29 wherein a position of the barcode is substantially unchanged during the single illumination session.

39. A multispectral sensor comprising:

an illumination source disposed to illuminate a barcode;

an imaging system disposed to receive light scattered from the barcode; and

a controller interfaced with the illumination system and the imaging system, the controller including;

instructions to illuminate the barcode with the illumination source under a plurality of distinct optical conditions during a single illumination session;

instructions to derive a spatiospectral multispectral image from light received by the imaging system separately for each of the plurality of optical conditions; and

instructions to decode the barcode from the spatiospectral multispectral image.

40. The multispectral sensor recited in claim 39 further comprising a first polarizer disposed to polarize the light provided by the illumination source, wherein:

the imaging system comprises a second polarizer disposed to polarize the light scattered from the barcode; and

the plurality of distinct optical conditions comprise distinct relative polarization conditions.

41. The multispectral sensor recited in claim 39 further comprising a first polarizer disposed to polarize the light provided by the illumination source, wherein:

the imaging system comprises a second polarizer disposed to polarize the light scattered from the barcode; and

the first and second polarizers are substantially in a crossed configuration.

42. The multispectral sensor recited in claim 39 wherein:

the imaging system comprises a color filter array having a plurality of distributed filter elements, each filter element being adapted to transmit light of one of a limited number of specified narrowband wavelength ranges; and

the plurality of distinct optical conditions comprise distinct wavelengths of illumination light within the specified narrowband wavelength ranges.

43. The multispectral sensor recited in claim 42 wherein the instructions to illuminate the barcode with the illumination source under the plurality of distinct optical conditions comprise instructions to illuminate the barcode with different wavelengths.

48. The method recited in claim 43 wherein deriving the image of the barcode comprises:

deriving a first image of the barcode from light received for the first polarization condition;

deriving a second image of the barcode from light received for the second polarization condition; and

performing a linear combination of the first and second images.

44. A method of imaging a barcode, the method comprising:

receiving light scattered from the barcode under first and second distinct polarization conditions during a single illumination session in which a position of the barcode is substantially unchanged, wherein the second polarization condition does not define a complementary state relative to the first polarization condition; and

deriving an image of the barcode from the received light.

45. The method recited in claim 44 wherein at least one of the first and second polarization conditions comprises a substantially random polarization condition.

46. The method recited in claim 44 wherein receiving light scattered from the barcode under one of the first and second distinct polarization conditions comprises:

illuminating the barcode with light having a first polarization; and

detecting light having the first polarization scattered from the barcode.

47. The method recited in claim 44 wherein receiving light scattered from the barcode under one of the first and second distinct polarization conditions comprises:

illuminating the barcode with light having a first polarization; and

detecting light having a second polarization complementary to the first polarization scattered from the barcode.