Multispectral detection and presentation of an object's characteristics

• US 20110112407A1
• Filed: 10/14/2010
• Published: 05/12/2011
• Est. Priority Date: 06/29/2006
• Status: Active Grant

• Current Assignee: AccuVein LLC
• Original Assignee: AccuVein LLC
• Inventors: Luciano, Vincent, Wood, Fred, Goldman, Ron
• Granted Patent: US 8,594,770 B2
• Time in Patent Office: Days
• US Class Current: 600/476
• CPC Class Codes: A61B 2090/366 using projection of images directly onto the body
• CPC Class Codes: A61B 5/0059 using light, e.g. diagnosis by transillumination, diascopy, fluorescence A61B5/0093, A61B5/1455, A61B5/02416 and A61B5/0261 take precedence
• CPC Class Codes: A61B 5/0075 by spectroscopy, i.e. measuring spectra, e.g. Raman spectroscopy, infrared absorption spectroscopy A61B5/0071 takes precedence
• CPC Class Codes: A61B 5/0077 Devices for viewing the surface of the body, e.g. camera, magnifying lens
• CPC Class Codes: A61B 5/0088 for oral or dental tissue
• CPC Class Codes: A61B 5/4887 Locating particular structures in or on the body
• CPC Class Codes: A61B 5/489 Blood vessels
• CPC Class Codes: A61M 5/427 Locating point where body is to be pierced, e.g. vein location means using ultrasonic waves, injection site templates

Abstract

An apparatus for capturing a multispectral image of an object is described. The apparatus includes one or more means for transmitting a beam of laser light at a first wavelength and a beam of laser light at one or more additional wavelengths different from the first wavelength. There is a means for causing the beams of laser light to travel in a coaxial path and a moving mirror. The beams of light bounce off the mirror thereby producing a two dimensional projection pattern. This pattern travels from the mirror along a first path to an object and wherein some of the laser light penetrates the object and travels to an internal structure of the object. The reflection of the laser light returns to a photo detector along a path different from said first path.

Claims

1. An apparatus for capturing a multispectral image of an object comprising one or more means for transmitting a beam of laser light at a first wavelength and a beam of laser light at one or more additional wavelengths different from the first wavelength, a means for causing said beams of laser light to travel in a coaxial path and a moving mirror wherein said beams of light bounce off said mirror thereby producing a two dimensional projection pattern, said pattern travelling from said mirror along a first path to an object and wherein some of the laser light penetrates said object and travels to an internal structure and wherein reflection of the laser light returns to a photo detector along a path different from said first path.

2. The apparatus according to claim 1 wherein said means for transmitting said beams of laser light is a tunable laser.

3. The apparatus according to claim 1 wherein said means for transmitting said beams of laser light is a wide-band laser.

4. The apparatus according to claim 1 wherein there is a first means for transmitting a beam of laser light at a first wavelength and a second means for transmitting a beam of laser light at a second wavelength wherein said first wavelength of light is different from the second wavelength of light.

5. The apparatus according to claim 1 wherein said means for causing said beams of laser light to travel in a coaxial path is a beam combiner.

6. The apparatus according to claim 1 wherein said mirror is a biaxial moving mirror.

7. The apparatus according to claim 1 wherein said mirror comprises an X mirror and a Y mirror.

8. The apparatus according to claim 1 wherein said object is a body part.

9. The apparatus according to claim 1 wherein said photo detector is a photo diode.

10. The apparatus according to claim 1 wherein there are one or more photo detectors.

11. The apparatus according to claim 10 wherein the reflected light received at said photo detectors is converted to an electrical signal, digitized and stored in a first frame memory location.

12. The apparatus according to claim 1 wherein multiple laser beams (Freq. 1-Freq. N) return to a first photo detector and a second photo detector along a first path and a second path.

13. The apparatus according to claim 12 wherein each laser Freq. 1-N is sequentially turned on for a period of time

14. The apparatus according to claim 12 wherein each laser Freq. 1-N is concurrently turned on for period of time

15. The apparatus according to claim 12 wherein each laser Freq. 1-N is sequentially turned on for one frame of projection.

16. The apparatus according to claim 15 wherein the reflected light received at said first and second photo detectors for said frame is stored in a first frame memory location.

17. The apparatus according to claim 16 wherein by sequentially stepping through Freq. 1-N a multispectral image is stored in sequential frames of memory location 1-N.

18. The apparatus according to claim 12 wherein said photo detectors are positioned such that no light from laser Freq. 1-N reflected from the surface of the object can reach said photo detector.

19. The apparatus according to claim 18 wherein said photo detectors touch said object.

20. The apparatus according to claim 18 wherein said beams of laser light upon hitting the internal structure are then carried internally to the object with a portion of light hitting said first and/or second photo detector.

21. The apparatus according to claim 12 wherein said photo detectors have color filters, said color filters limiting the response of each detector to a narrow band of wavelength.

22. The apparatus according to claim 18 wherein said filter can be mechanically changed.

23. The apparatus according to claim 18 wherein said filter can be changed electro-optically.

24. The apparatus according to claim 12 wherein said photo detectors have light of different wavelengths directed toward different detector elements by an optical element.

25. The apparatus according to claim 12 wherein said photo detectors have light of different wavelengths directed toward different detector elements by a grating.

26. The apparatus according to claim 12 wherein an array of photo detectors is positioned anywhere on the object except along said first optional path.

27. The apparatus according to claim 12 wherein a ring of photo detectors is positioned around the surface of an object.

28. The apparatus according to claim 27 wherein said ring is positioned against the surface of said object.

29. The apparatus according to claim 28 wherein the beams of laser light 1-N penetrates the object and interact with said inner structure and wherein the beams of laser light 1-N scatter inside said object with a portion of the light being returned to said photo detector ring.

30. The apparatus according to claim 29 wherein the power of the lasers 1-N can be increased substantially to reach deeper inner structures without having the surface reflections creating noise.

31. The apparatus according to claim 1 wherein the object is a tooth.

32. An apparatus for projecting an image comprising a means for controlling the brightness of a laser beam wherein the intensity of said beam is varied a multiplicity of times during a scan, to produce a more uniform reflection, and wherein each individual segment of a scan has a memory location and wherein each segment has a defined location on the object defined by a time slot in a frame.

33. The apparatus according to claim 32 wherein each segment is a pixel.

34. The apparatus according to claim 33 wherein at least one photo detector receives reflected light from said object and provides a corresponding voltage to an amplifier, and wherein output from said amplifier is provided to a comparator that in turn provides a single bit of data, said bit indicating whether the laser beam was “

too bright”

or “

too dark”

for that pixel.

35. The apparatus according to claim 34 wherein the data is then stored as Pixel brightness information and is updated with every frame.

36. The apparatus according to claim 35 wherein stored pixel brightness is changed up or down depending on the photo detector bit, until the voltage corresponding to the reflected light as received by the photo detectors becomes nearly equal to the comparator threshold

37. The apparatus according to claim 36 wherein pixel data is always changed by at least one bit every frame for maximum light contrast sensitivity.

38. The apparatus according to claim 36, where there is a plurality of comparators with different, but closely-spaced thresholds providing multiple bits of data, said bits indicating whether the laser beam was “

too bright”

or “

too dark”

for that pixel with greater precision

39. The apparatus according to claim 37 wherein there is a plurality of photo detectors

40. The apparatus according to claim 37 wherein there is a photo detectors array.

41. The apparatus according to claim 37 wherein said amplifier is DC coupled.

42. The apparatus according to claim 37 wherein the comparator has one bit logic output.

43. The apparatus according to claim 33 wherein the memory location is in a frame memory buffer.

44. The apparatus according to claim 43 wherein the laser beam brightness is controlled by a high speed digital to analog converter.

45. The apparatus according to claim 44 wherein said beam is varied more than one hundred times each scan.

46. The apparatus according to claim 45 wherein said beam is varied more than one thousand times each scan.

47. The apparatus according to claim 46 wherein said laser is calibrated by driving said laser to a defined maximum and then to a minimum brightness and wherein during minimum brightness, DC bias on the photo detector amplifier is adjusted to compensate for any change in ambient room lighting.

48. The apparatus according to claim 32 wherein there are multiple lasers of different wavelength.

49. The apparatus according to claim 32 wherein the laser is tunable

50. The apparatus according to claim 32 wherein the laser is wide-band

51. The apparatus according to claim 50 wherein each laser is on sequentially for a period of time

52. The apparatus according to claim 50 wherein each laser is on concurrently for a period of time

53. The apparatus according to claim 50 wherein each laser is on for a frame of projection

54. The apparatus according to claim 51 wherein there are multiple photo detectors that are provided with a filter so that each photo detector receives only one of the specific frequencies of laser light.

55. The apparatus according to claim 54 wherein each color has a corresponding frame buffer memory.