Optical probe having and methods for difuse and uniform light irradiation

• US 20020007111A1
• Filed: 01/19/2001
• Published: 01/17/2002
• Est. Priority Date: 07/08/1998
• Status: Active Grant

• Current Assignee: Lifespex, Inc.
• Original Assignee: Lifespex, Inc.
• Inventors: Thomas, Ann M., McConaghy, Robert F., Parnell, Julie R., Hildwein, Roger L., Deckert, Curtis K., Wilcox, Robert L.
• Granted Patent: US 6,487,440 B2
• Time in Patent Office: Days
• US Class Current: 600/177
• CPC Class Codes: G02B 23/2407 Optical details
• CPC Class Codes: G02B 23/2461 Illumination
• CPC Class Codes: G02B 23/2469 using optical fibres

Abstract

A variety of optical probes and methods have utility in the examination of various materials, especially materials in the interior of cavities having restricted access through orifices or passageways. One type of such optical probe is elongated and includes a distal optical window, a divergent light source, a spatial mixer, and a light collector. Light from the light source is mixed in the spatial mixer to achieve uniform diffuse light in the vicinity of the optical window. The light collector receives light from the target through the spatial mixer. The optical probe may be made of two sections, a reusable section and a disposable. The disposable is elongated and contains a mounting section, an inside surface suitable for the spatial mixing of light, and an optical element which helps to seal the reusable probe section from the target.

Claims

1. An optical probe having a distally disposed optical window, comprising:

a light collector having an axis of light collection passing through the optical window and a focal plane generally proximate the optical window;

a light source having a light projection pattern about the axis of light collection; and

a spatial mixer having a proximal end in optical communication with the light source, a distal end in optical communication with the optical window, and an axis of light projection passing through the optical window, the spatial mixer further having a light mixing surface partially intersected by the light projection pattern of the light source to establish a distribution of irradiation ray angles proximate the optical window that has a maximum away from normal and near-normal to the axis of light projection.

2. An optical probe as in claim 1 wherein the axis of light collection and the axis of light projection are coaxial at the optical window.

3. An optical probe as in claim 2 wherein the axis of light collection and the axis of light projection are coaxial through the spatial mixer.

4. An optical probe as in claim 1 further comprising a unitary body having a distal end containing the optical window and a proximate end, the light collector, the light source, and the spatial mixer being mounted to the body.

5. An optical probe as in claim 4 further comprising a handle coupled to the body near the proximal end thereof.

6. An optical probe as in claim 1 further comprising a body having a proximal section and a distal section containing the optical window.

7. An optical probe as in claim 6 further comprising a handle coupled to the proximal body section.

8. An optical probe as in claim 6 wherein the distal body section is removably coupled to the proximal body section.

9. An optical probe as in claim 8 wherein the distal body section is reusable.

10. An optical probe as in claim 8 wherein the distal body section is disposable.

11. An optical probe as in claim 10 wherein the spatial mixer is mounted to the distal body section and the light collector and the light source are mounted to the proximal body section.

12. An optical probe as in claim 10 wherein the light collector, the light source, and the spatial mixer are mounted to the proximal body section.

13. An optical probe as in claim 10 wherein the distal section is single use.

14. An optical probe as in claim 1 wherein the optical window is an opening in a distal end of the optical probe.

15. An optical probe as in claim 14 wherein the axis of light collection passes through the spatial mixer, further comprising an optical element disposed in the spatial mixer along the axis of light collection.

16. An optical probe as in claim 14 wherein the axis of light collection passes through the spatial mixer, further comprising an optical element disposed in the spatial mixer near the proximal end thereof and along the axis of light collection.

17. An optical probe as in claim 1 further comprising an optical element disposed in the optical window.

18. An optical probe as in claim 17 wherein the optical element is a flat rigid window.

19. An optical probe as in claim 17 wherein the optical element is a shaped lens.

20. An optical probe as in claim 17 wherein the optical element comprises a surface contoured to generally conform with the surface of a human cervix.

21. An optical probe as in claim 17 wherein the axis of light collection passes through the spatial mixer, further comprising another optical element disposed in the spatial mixer along the axis of light collection.

22. An optical probe as in claim 17 wherein the axis of light collection passes through the spatial mixer, further comprising another optical element disposed in the spatial mixer near the proximal end thereof and along the axis of light collection.

23. An optical probe as in claim 1 wherein the light collector comprises:

a telecentric lens system; and

a fiber optics bundle coupled to the telecentric lens system for carrying an image from the telecentric lens system to an external detector.

24. An optical probe as in claim 1 wherein the light collector comprises:

a near-telecentric lens system; and

a fiber optics bundle coupled to the near-telecentric lens system for carrying an image from the near-telecentric lens system to an external detector.

25. An optical probe as in claim 1 wherein the light collector comprises:

a non-telecentric lens system; and

means for correcting the non-telecentric lens system for non-uniformity across the field of view of the optical probe.

26. An optical probe as in claim 1 wherein the light collector comprises a lens system, the optical probe further comprising a light detector optically coupled to the lens system.

27. An optical probe as in claim 26 wherein the light detector comprises a CCD camera.

28. An optical probe as in claim 1 wherein the light collector has a field of view that excludes the mixing surface of the spatial mixer and includes substantially the entire area of the optical window.

29. An optical probe as in claim 1 wherein the focal plane of the light collector is distal to the optical window.

30. An optical probe as in claim 1 wherein the focal plane of the light collector is proximal to the optical window.

31. An optical probe as in claim 1 wherein the light source comprises a plurality of optical fibers arranged on all sides of the light collector, each of the fibers having an optical axis directed toward the optical window.

32. An optical probe as in claim 1 wherein the light source comprises a light guide arranged on all sides of the light collector, the light guide projecting light generally toward the optical window.

33. An optical probe as in claim 1 wherein the light source comprises a plurality of light guides arranged a bout the light collector.

34. An optical probe as in claim 33 wherein the light guides have respective optical axes directed toward the optical window.

35. An optical probe as in claim 1 wherein the light source comprises a plurality of optical fibers arranged about the light collector.

36. An optical probe as in claim 35 wherein the optical fibers have respective optical axes directed toward the optical window.

37. An optical probe as in claim 1 wherein the light source comprises a plurality of light emitting diodes arranged about the light collector.

38. An optical probe as in claim 37 wherein the light emitting diodes have respective optical axes directed toward the optical window.

39. An optical probe as in claim 1 wherein the light projection pattern of the light source partially intersects the light mixing surface to establish a distribution of ray angles proximate the optical window that has a maximum near-parallel to the axis of light projection.

40. An optical probe as in claim 1 wherein the mixing surface comprises a light scattering surface.

41. An optical probe as in claim 1 wherein the mixing surface comprises a light scattering surface in combination with a specular surface over respective areas of the mixing surface.

42. An optical probe as in claim 1 wherein the mixing surface comprises a light scattering surface in combination with a light absorbing surface over respective areas of the mixing surface.

43. An optical probe as in claim 1 wherein the mixing surface comprises a light scattering surface in combination with a specular surface and a light absorbing surface over respective areas of the mixing surface.

44. An optical probe as in claim 1 wherein the mixing surface comprises a metallic foil.

45. An optical probe as in claim 1 wherein the mixing surface comprises a plastic having a surface finish in the range of about 4 microinches to about 63 microinches.

46. An optical probe as in claim 1 wherein the light projection pattern is a ring.

47. An optical probe as in claim 1 wherein the light projection pattern is an ellipse.

48. An optical probe as in claim 1 wherein the light projection pattern is a triangle.

49. An optical probe for examining, through an optical window therein, living tissue in the interior of cavities having restricted access through orifices or passageways, comprising:

a body having an elongated distal section containing the optical window, and a proximal section;

a lens system mounted in the body, the lens system having an optical axis passing through the optical window of the probe and a focal plane lying generally proximate to the optical window;

a light source mounted in the body about the lens system, the light source being coaxial with the lens system and having a direction of light projection generally toward the optical window; and

an elongated inside surface having one end disposed generally about the light source and another end disposed generally about the optical window, the inside surface comprising a light scattering surface and the light projection at least partially intersecting the light scattering surface to establish a distribution of ray angles proximate the optical window that has a maximum near-parallel to the optical axis of the lens system.

50. An optical probe as in claim 49 further comprising a lens mounted to the distal section along the optical axis of the lens system and at the optical window, wherein the lens system in combination with the lens is a telecentric lens system.

51. An optical probe as in claim 49 further comprising a lens mounted to the distal section along the optical axis of the lens system.

52. An optical probe as in claim 49 wherein the light source is a ring irradiator.

53. An optical probe as in claim 52 wherein the ring irradiator comprises a plurality of optical fibers arranged in a ring.

54. An optical probe as in claim 52 wherein the ring irradiator comprises a cylindrical light guide.

55. An optical probe as in claim 52 wherein the ring irradiator comprises a plurality of light guides arranged in a ring.

56. An optical probe having a distally disposed optical window, comprising:

a light collector having an axis of light collection passing through the optical window and a focal plane generally proximate the optical window;

a light source having a plurality of light emitting areas disposed about the axis of light collection; and

a spatial mixer having a proximal end in optical communication with the light source and a distal end in optical communication with the optical window to establish a direction of light projection generally toward the optical window and generally along at least part of the axis of light collection, the spatial mixer further having a light mixing surface at least partially intersected by rays of light from the light emitting areas to establish a diffuse light proximate the optical window having a distribution of irradiation ray angles that has a maximum away from normal and near-normal to the direction of light projection.

57. An optical probe as in claim 56 wherein the plurality of light emitting areas of the light source are merged about the axis of light collection.

58. An optical probe as in claim 57 wherein the plurality of light emitting areas of the light source are disposed about the axis of light collection in a ring centered on the axis of light collection.

59. An optical probe as in claim 57 wherein:

the light collector comprises a periphery generally parallel to the axis of collection; and

the light source comprises a liquid light guide having a distal end directed generally toward the optical window and a portion in proximity to the distal end disposed generally throughout the periphery of the light collector.

60. An optical probe as in claim 56 wherein the plurality of light emitting areas of the light source are discretely disposed about the axis of light collection.

61. An optical probe as in claim 60 wherein the plurality of light emitting areas of the light source are disposed about the axis of light collection in a ring centered on the axis of light collection.

62. An optical probe as in claim 61 wherein the light emitting areas emit light in a cone.

63. An optical probe as in claim 60 wherein:

the light collector comprises a periphery generally parallel to the axis of collection; and

the light source comprises a plurality of optical fibers having respective distal ends directed generally toward the optical window and respective lengths in proximity to the ends disposed generally at the periphery of the light collector.

64. An optical probe as in claim 60 wherein:

the light collector comprises a periphery generally parallel to the axis of collection; and

the light source comprises a plurality of light guides having respective distal ends directed generally toward the optical window and respective lengths in proximity to the ends disposed generally at the periphery of the light collector.

65. An optical probe as in claim 56 wherein the plurality of light emitting areas of the light source are disposed about the axis of light collection in a ring.

66. An optical probe as in claim 56 wherein the plurality of light emitting areas of the light source are disposed about the axis of light collection in an ellipse.

67. An optical probe as in claim 56 wherein the plurality of light emitting areas of the light source are disposed about the axis of light collection in a triangle.

68. An optical probe as in claim 56 wherein the axis of light collection and the direction of light projection are coaxial at the optical window.

69. An optical probe as in claim 68 wherein the axis of light collection and the direction of light projection are coaxial through the spatial mixer.

70. An optical probe as in claim 56 wherein the rays of light from the light source that intersect the light mixing surface establish, along with direct rays of light from the light source, a diffuse light proximate the optical window having a distribution of ray angles that has a maximum near-parallel to the direction of light projection.

71. An optical probe as in claim 56 further comprising a reusable body containing the light collector, the light source, the optical window, and the spatial mixer.

72. An optical probe as in claim 56 further comprising:

a reusable proximal body section containing the light collector and the light source; and

a disposable distal section removably coupled to the proximal body section and containing the optical window and the spatial mixer.

73. An optical probe as in claim 72 wherein the optical element is disposed in proximity to the light emitting areas of the light source and recessed from the distal end of the disposable distal section.

74. An optical probe as in claim 73 wherein the disposable distal section comprises a plastic tube.

75. An optical probe as in claim 74 wherein the spatial mixer comprises an interior surface of the plastic tube disposed at least partially between the optical element and the optical window.

76. An optical probe as in claim 75 wherein the spatial mixer has a surface finish in the range of about 4 microinches to about 63 microinches.

77. An optical probe as in claim 76 wherein the optical element comprises an anti-fog coating on at least a surface facing the optical window.

78. An optical probe as in claim 77 wherein the spatial mixer comprises an anti-fog coating on at least a portion thereof between the optical element and the optical window.

79. An optical probe as in claim 56 wherein the light collector has a field of view that excludes substantially the entire spatial mixer and includes substantially the entire area of the optical window.

80. An optical probe as in claim 79 wherein the light collector has a focal plane distal of the optical window.

81. An optical probe as in claim 79 wherein the light collector has a focal plane proximal of the optical window.

82. An optical probe as in claim 79 wherein the light collector has a focal plane at the optical window.

83. An optical probe as in claim 56 wherein the light collector comprises:

a lens system; and

an optical transmission medium coupled to the lens system and extending to an external detector.

84. An optical probe as in claim 56 wherein the light collector comprises a lens system, the optical probe further comprising a light detector optically coupled to the lens system.

85. An optical probe as in claim 84 wherein the light detector comprises a CCD camera.

86. A disposable for an optical probe, the disposable having a distal end to contact a target having a fluid associated therewith and a proximal end to mount to a reusable optical probe section, the disposable comprising:

a body having a mounting surface toward the proximal end and a light mixing inside surface toward the distal end; and

an optical window element disposed within the body, the optical window element and the body proximal of the optical window element being barriers to the fluid.

87. A disposable as in claim 86 wherein the body comprises a tube and the light mixing inside surface comprises a metallic foil disposed on the inside of the tube.

88. A disposable as in claim 87 wherein the tube is paper.

89. A disposable as in claim 87 wherein the tube is plastic.

90. A disposable as in claim 87 wherein the tube is extruded aluminum.

91. A disposable as in claim 86 wherein the body comprises an extruded aluminum tube and the light mixing inside surface comprises an inside surface of the extruded aluminum tube having a light scattering surface treatment.

92. A disposable as in claim 86 wherein the body comprises a tube and the light mixing inside surface comprises a liner having a light scattering property disposed on the inside of the tube.

93. A disposable as in claim 86 wherein the body comprises a tube and the light mixing inside surface comprises an inside surface of the tube having a light scattering treatment.

94. A disposable as in claim 86 wherein the body comprises a tube and the mounting surface comprises a mechanical connector integral with the tube.

95. A disposable as in claim 94 wherein the tube is paper.

96. A disposable as in claim 94 wherein the tube is plastic.

97. A disposable as in claim 94 wherein the tube is extruded aluminum.

98. A disposable as in claim 86 wherein the body comprises:

a first tube, the light mixing inside surface comprising a metallic foil disposed on the inside of the first tube; and

a second tube coupled to the first tube, the mounting surface comprising a mechanical connector integral with the second tube.

99. A disposable as in claim 98 wherein the optical window element is mounted within the first tube.

100. A disposable as in claim 98 wherein the optical window element is mounted at a distal end of the first tube.

101. A disposable for an optical probe, the disposable having a distal end to contact a target having a fluid associated therewith and a proximal end to mount to a reusable optical probe section, the disposable comprising:

a body having an inside surface bounding an interior space extending between the proximal end and the distal end, the inside surface comprising at least in part a light mixing surface;

an optical element disposed across the interior space, the optical element and the body at least proximal of the optical element being barriers to the fluid; and

a reusable optical probe section connector integrated with the body.

102. A disposable as in claim 101 wherein the optical element is recessed from the distal end of the body.

103. A disposable as in claim 102 wherein at least part of the light mixing surface is disposed between the optical element and the distal end of the body.

104. A disposable as in claim 101 wherein the optical element is disposed at the distal end of the body.

105. A disposable as in claim 101 wherein the body comprises a plastic tube having an inside surface of a predetermined roughness surrounding at least a part of the interior space, the spatial mixer comprising the inside surface of the plastic tube.

106. A disposable as in claim 101 wherein the body comprises a paper tube having an inside foil lining, the foil lining having an inside surface of a predetermined roughness surrounding at least a part of the interior space, the spatial mixer comprising the inside surface of the foil lining.

107. A disposable as in claim 101 wherein the body comprises a metallic tube having an inside surface of a predetermined roughness surrounding at least a part of the interior space, the spatial mixer comprising the inside surface of the metallic tube.

108. A disposable as in claim 101 wherein the body comprises at least one extruded tubular member.

109. A disposable as in claim 108 wherein the reusable optical probe section connector is coupled to the extruded tubular member.

110. A disposable as in claim 101 wherein the body comprises a plurality of molded members.

111. A disposable as in claim 101 wherein the body comprises a plurality of molded members, the molded members further comprising respective portions of the reusable optical probe section connector.

112. A disposable for an optical probe, the disposable having a distal end to contact a target having a fluid associated therewith and a proximal end to mount to a reusable optical probe section, the disposable comprising:

a tubular plastic body having an inside surface bounding an interior space extending between the proximal end and the distal end, the inside surface comprising at least in part a light mixing surface;

an optical element disposed across the interior space, the optical element and the body being barriers to the fluid; and

a reusable optical probe section connector integrated with the body.

113. A disposable as in claim 112 wherein the light mixing surface has a finish in the range of about 4 microinches to about 63 microinches.

114. A disposable as in claim 113 wherein the body comprises an assembly of extruded plastic tubular members.

115. A disposable as in claim 114 wherein the reusable optical probe section connector is assembled to the body.

116. A disposable as in claim 113 wherein the body comprises an assembly of molded members.

117. A disposable as in claim 116 wherein the molded members including respective parts of the reusable optical probe section connector.

118. A disposable as in claim 113 further comprising an anti-fog material disposed on at least a surface of the optical element facing the distal end of the disposable.

119. A disposable as in claim 118 further comprising an anti-fog material disposed on at least a portion of the light mixing surface.