Miniature endoscope system
The present invention relates to a small diameter endoscope in which a handle is removably attached to a probe. The probe includes a fiber optic illumination channel that is concentric about an imaging channel. The handle includes an imaging device that detects light from the imaging channel and a sterile barrier that can be extended over the handle for use. Relay optics couples the small diameter imaging channel to the imaging device in the handle. The probe has a mounting hub that connects the probe to the handle and also serves to optically couple the fiber optic illumination channel to a light source.
1. A miniature endoscope for orthopedic imaging comprising:
a probe for orthopedic diagnostic imaging, the probe including a fiber optic imaging waveguide that transmits an image, and having a diameter of less than 2 mm and a length between 2 cm and 10 cm, the probe having a mounting hub;
a fiber optic illumination channel within the probe that is concentric about the optical waveguide, the illumination channel being positioned between an inner sheath and an outer sheath;
a handle removeably attached to the mounting hub of the probe with a connector;
a light source that is optically coupled to the fiber optic illumination channel with the mounting hub;
a cannula that receives a distal end of the probe such that the outer sheath slides within the cannula, the cannula having a locking mechanism at a proximal end that attaches to the probe;
a sterile barrier attached to the mounting hub and that can be extended over the handle;
an optical lens coupled to a distal end of the waveguide;
an optical relay mounted in the handle and that is optically coupled to a proximal end of the waveguide; and
an imaging device mounted in the handle at a proximal end of the optical relay that receives an image from the optical waveguide.
2. The miniature endoscope of claim 1 wherein the endoscope has an outer diameter of 1.6 mm or less.
3. The miniature endoscope of claim 1 wherein the waveguide has an outer diameter between 0.6 and 1.6 mm.
4. The miniature endoscope of claim 1 wherein the illumination channel includes a binary phase ring which disperses light from the illumination channel.
5. The miniature endoscope of claim 1 wherein the waveguide comprises a glass having a refractive index in the range between 1.6 and 1.9.
6. The miniature endoscope of claim 1 wherein the waveguide comprises a glass rod.
7. The miniature endoscope of claim 1 wherein the optical waveguide further comprises a light absorbing layer having a thickness between 5 and 10 μm.
8. The miniature endoscope of claim 1 wherein the optical waveguide further comprises a light absorbing layer having an extramural absorption glass.
9. The miniature endoscope of claim 1 wherein the optical waveguide further comprises a light absorbing layer having a refractive index of 1.6 or less.
10. The miniature endoscope of claim 1 wherein the illumination channel has a wall thickness in a range of 0.1 mm and 0.2 mm.
11. The miniature endoscope of claim 1 wherein the illumination channel has a refractive index in a range between 1.4 and 1.6.
12. The miniature endoscope of claim 1 wherein the outer sheath comprises a metal tube.
13. The miniature endoscope of claim 12 wherein the outer sheath comprises a polyamide coating.
14. The miniature endoscope of claim 13 wherein the polyamide coating has a thickness between 100 and 150 μm.
15. The miniature endoscope of claim 1 wherein the optical relay comprises one or more lenses.
16. The miniature endoscope of claim 1 wherein the optical lens comprises a plastic lens.
17. The miniature endoscope of claim 1 wherein the imaging device comprises a charge coupled device.
18. The miniature endoscope of claim 1 wherein the cannula further comprises a distal needle that penetrates tissue.
19. The miniature endoscope of claim 1 further comprising a display connected to the imaging device.
20. The miniature endoscope of claim 1 wherein the illumination channel is optically coupled to a light source with a lens in the handle.
21. The miniature endoscope of claim 1 further comprising an optical coupler that optically connects the light source to the illumination channel.
22. The miniature endoscope of claim 1 wherein the cannula further comprises a fluid delivery port.
23. The miniature endoscope of claim 22 wherein the barrier is attached to a rigid waveguide housing that is connected to the handle.
24. The miniature endoscope of claim 1 wherein the light source comprises a lamp within the handle that is optically coupled to the illumination channel.
25. The endoscope of claim 1 further comprising a tube around the optical waveguide and an outer tube around the fiber optic illumination channel.
26. The endoscope of claim 25 wherein the outer tube is a plastic material.
27. The endoscope of claim 25 wherein the tube comprises a metal.
28. The endoscope of claim 1 wherein the endoscope probe has a length to diameter ratio between 40:1 and 60:1.
29. The endoscope of claim 1 further comprising a computer connected to the imaging device.
30. The endoscope of claim 29 further comprising an image processing sequence.
31. The endoscope of claim 30 wherein the image processing sequence subtracts a stored light distribution pattern from a video image.
32. The endoscope of claim 31 wherein the stored light distribution pattern corresponds with a light reflection pattern for the endoscope.
33. The endoscope of claim 1 wherein the concentric illumination channel has a thickness of 10 microns.
34. The endoscope of claim 1 wherein the concentric illumination channel has a thickness of 30 microns.
35. A miniature endoscope for orthopedic imaging comprising:
a probe for orthopedic diagnostic imaging, the probe including a fiber optic imaging channel having a diameter in a range of 0.6 mm to 1.6 mm and the probe having a diameter less than 2 mm and a mounting hub;
a tube surrounding the imaging channel;
a fiber optic illumination channel within the probe that is concentric about the tube and the imaging channel and a light source that is optically coupled to the fiber optic illumination channel with the mounting hub attached to the handle, the illumination channel having a thickness in a range of 0.1 mm to 0.2 mm;
an outer tube around the fiber optic illumination channel;
a handle removably attached to the probe with a connector;
a cannula that receives a distal end of the probe such that the distal end of the probe slides within the cannula, the cannula having a locking mechanism at a proximal end that attaches to the probe;
a sterile barrier attached to the mounting hub that can be extended over the handle;
a first lens and a second lens that are optically coupled to a distal end of the imaging channel;
an optical relay mounted in the handle and optically coupled to a proximal end of the imaging channel; and
an imaging device mounted in the handle and optically coupled to a proximal end of the optical relay.
36. The miniature endoscope of claim 35 wherein the imaging device comprises a charge coupled device.
37. The miniature endoscope of claim 35 wherein the imaging channel comprises a transparent material having a refractive index of at least 1.6.
38. The miniature endoscope of claim 37 wherein the imaging light channel comprises a glass rod.
39. The miniature endoscope of claim 38 wherein the glass rod comprises an F2 or an F7 glass.
40. The miniature endoscope of claim 35 further comprising a light absorbing layer around the imaging channel.
41. The miniature endoscope of claim 35 wherein the illumination channel is coupled to the light source with a fiber optic connector.
42. The miniature endoscope of claim 35 wherein the endoscope has a display connected to the imaging device for arthroscopic examination.