Claims
- 1. An automatic system for inspecting stents and other precision cut tubes comprising:
(A) a electronic camera comprising a lens and at least one photodetector;
(i) said lens configured and dimensioned for focusing an image of a precision cut tube on said at least one photodetector; (B) a rotary stage; (C) a mandrel disposed on said rotary stage, said mandrel being dimensioned and configured to accept a precision cut tube to be inspected by said camera;
(i) said rotary stage positioned such that said mandrel is in the field of view of said lens; (D) a computer based electronic imaging system, functionally connected to said camera, that creates a line-by-line image of said tube as said tube rotates on said mandrel under said camera; and (E) a light source to provide necessary illumination to create said image.
- 2. An automatic inspection system as in claim 1 wherein said electronic camera is a linear array camera.
- 3. An automatic inspection system as in claim 1 wherein said mandrel is made of a translucent material.
- 4. An automatic inspection system as in claim 1 wherein said rotary stage is motor driven.
- 5. An automatic inspection system as in claim 1 further comprising an encoder; (A) said encoder is functionally connected to said rotary stage and said computer system;
(B) said encoder creates pulses as said rotary stage rotates; (C) said pulses are transferred to and counted by said computer system; and (D) said computer uses said pulses to precisely trigger a line-by-line creation of an image of said tube as said tube rotates under said camera.
- 6. An automatic inspection system as in claim 1 whereby said computer based electronic imaging system analyzes said image and determines the conformance of said tube to a known dimensional tolerance.
- 7. An automatic inspection system as in claim 1 whereby said computer based electronic imaging system further analyzes said image for cosmetic and functional defects in said tube.
- 8. An illumination system for inspecting stents and other precision cut tubes comprising:
(A) a translucent mandrel; and (B) a substantially linear light source disposed substantially along the length of said mandrel, such that light emitted from said linear light source is directed through said mandrel in the direction of an imaging lens.
- 9. An illumination system as in claim 8 wherein said linear light source is a fiber optic light line.
- 10. An illumination system as in claim 8 wherein said linear light source is an array of light emitting diodes.
- 11. An illumination system as described in claim 8, further comprising a condenser lens disposed between said light source and said mandrel that collects light from said light source and focus said light substantially in a linear pattern along the length of said mandrel
- 12. An illumination system for inspecting stents and other precision cut tubes comprising:
(A) a translucent mandrel upon which a precision cut tube is mounted; (B) a light source; (C) a condenser lens disposed between said light source and said mandrel that collects the light from said light source and focus said light substantially in a linear pattern along the length of said mandrel; and (D) said light emitted from said light source is directed through said mandrel in the direction of an imaging lens.
- 13. An illumination system as described in claim 12, whereby said condenser lens provides a substantially collimated plane of light directed towards said translucent mandrel.
- 14. A method for measuring wall thickness of a tube comprising:
(A) Disposing at least two electronic linear position displacement transducers directly opposing each other and centered about said tube placed on a rod; (B) said transducers contacting and exerting pressure on the wall of said tube; and (C) calculating the average wall thickness of the tube by taking one half the absolute difference between the displacements of said transducers when each is in contact with said rod compared to the displacements of the transducers when each is in contact with said tube.
- 15. A method for measuring wall thickness as described in claim 14 wherein said measuring transducers are mounted on a single axis stage in line with said cut tube being inspected allowing for measurements at any location along said cut tube.
- 16. A method for measuring wall thickness as described in claim 14 further comprising an optical magnification system utilizing a visualization apparatus to allow an operator to visualize said tube walls that are being contacted.
- 17. A method for measuring wall thickness as described in claim 16 wherein said visualization apparatus is an eyepiece.
- 18. A method for measuring wall thickness as described in claim 16 wherein said visualization apparatus is a video monitor.
- 19. A method for measuring wall thickness as described in claim 15 further comprising an automated motion control system that will automatically drive said two electronic linear displacement transducers on said single axis stage to sites selected by an operator in an automatic inspection program.
- 20. A method for measuring wall thickness as described in claim 15 wherein:
(D) Said at least two electronic linear position displacement transducers directly opposing each other and centered about said tube disposed on said rod; (E) said transducers contacting and exerting pressure on the wall of said tube; (F) at least one transducer comprising a contact tip larger than the typical size of a cut feature on said tube; and (G) at least one transducer comprising a contact tip as small or smaller than the typical size of a cut feature on said tube.
- 21. A method for measuring wall thickness as described in claim 14 wherein:
at least one transducer comprising a tip as small or smaller than the typical size of a cut feature, and contacting said tube; at least one opposing transducer with a tip larger then the typical size of a cut feature, and linearly shifted along the axis of said tube and pressing against said mandrel, referencing the outer diameter of said tube; calculating the difference in transducer displacements of said smaller tipped and said larger tipped transducer measurements which is the thickness of said wall contacted by said smaller tipped transducer.
- 22. A method as in claim 21 further comprising an automated motion control system that will automatically drive said at least two electronic linear displacement transducers on said single axis stage to sites preselected by an operator in an automatic inspection program.
- 23. An illumination system for illuminating a section of a cut tube comprising:
(A) a rectangular diffusive light source that creates a highly even illumination along the length of said cut tube;
(i) said rectangular diffuse light source being at least as long as said cut tube and at least as wide as said cut tube; (ii) a bottom edge of said light source is disposed along the length of said cut tube; (iii) said light source being positioned in close proximity to said tube being illuminated; (iv) said rectangular diffusive light source is positioned in a plane parallel to the plane formed by a line along the centerline of the length of said cut tube and the centerline of an optical axis of a camera looking down on said cut tube.
- 24. An illumination system as in claim 23 wherein the width of said diffuse light source is two to ten times the diameter of said tube.
- 25. An illumination system as described in claim 23 further comprising a second rectangular diffusive light source to illuminate portions of said tube not illuminated by a first light source, said second diffuse light source disposed parallel to and directly facing said first light source with said tube directly between said first and said second light sources.
- 26. An illuminator as described in claim 23 wherein said camera is a linear array camera and said camera is viewing an area of said cut tube that is being illuminated by said light source; said camera being disposed such that its center of focus is away from the centerline of the cut tube so as to create an electronic image of said cut tube that includes both surface features of the cut tube and sidewall views.
- 27. An illuminator as described in claim 23 further comprising an optical beamsplitter disposed between said camera and said cut tube; said beamsplitter is at least as long as the section of said tube that is being viewed by said camera; said beamsplitter is disposed so as to direct light from said light source onto said tube so as to evenly illuminated the length of said tube at its apogee.
- 28. A method for software based image analysis comprising:
(A) selecting a recurring pattern set in an image; (B) selecting one pattern within said pattern set as an anchor pattern; (C) setting vision tools at specific locations within said image; (D) software finding the anchoring pattern on said image; (E) software iteratively examining areas adjacent to said anchor pattern until all areas of said image are examined.,
- 29. A method for software based image analysis system as in claim 28 wherein said vision tool makes measurements.
- 30. A method for software based image analysis system as in claim 28 wherein said vision tool finds defects.
- 31. A method for software based image analysis system as in claim 28 whereby at each location of each found pattern within said image said selected vision tool for that pattern is applied; results of all applied vision tools are tabulated in a database.
- 32. A software based image analysis system as in claim 28 further comprising:
(F) the location of each found pattern and associated vision tool being graphically displayed by overlaying said found pattern or tool directly on said image being analyzed.
- 33. A software based image analysis system as in claim 28 whereby: after said vision tools are placed in a position by said operator, said software can automatically optimize said placed vision tools' orientation on said found image based on the overall match fit of said found pattern to the analyzed section of said image.
- 34. A means for measuring the thickness of a tube wall comprising:
(A) mounting a cut tube onto a rigid rod; (B) moving at least two contact tips into contact with said tube; (C) imaging said tips with an optical system when said tips are in contact with said cut tube; and (D) converting the optical image into a measurement.
- 35. A means for measuring the thickness of a tube wall as in claim 34 wherein said contact tips are brought into contact with said tube from opposing sides of said tube.
- 36. A measuring system as described in claim 34 wherein said optical system is a video camera.
- 37. A measuring system as in claim 34 further comprising cross-hairs on the video screen; said cross hairs being aligned with features on said contact tips; the distance between these features as defined by the disposition of said crosshair indicates said wall thickness when the diameter of the rigid rod and length of the tips are accounted for.
- 38. A measuring system as in claim 34 further comprising a computer to analyze said image and calculate said wall thickness.
- 39. A measuring system as in claim 34 whereby at least one of said contact tips has a fine point.
- 40. A measuring system as described in claim 34 wherein two successive wall thickness measurements are taken; One measurement taken with said tip in contact with said rigid rod, while said fine tip is in contact with said tube wall; The other measurement taken with said tip in contact with said rigid rod, while said fine tip is in contact with said tube wall feature; The difference between these two measurements gives the thickness of a specific feature.
- 41. A measuring system as in claim 40 wherein said optical system used for imaging the tips is a video camera.
- 42. A measuring system as in claim 40 further comprising cross-hairs on a video screen; said cross hairs being aligned with features on said contact tips; the distance between these features as defined by the disposition of said crosshair indicates said wall thickness when the diameter of the rigid rod and length of the tips are accounted for.
- 43. A measuring system as in claim 40 further comprising a computer to analyze the image and calculate said wall thickness.
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application is a divisional of U.S. patent application No. 09/842,579, filed Apr. 26, 2001, which claimed the benefit of U.S. provisional patent application No. 60/201,791, filed May 4, 2000, the disclosures of which are hereby incorporated herein by reference thereto.
Provisional Applications (1)
|
Number |
Date |
Country |
|
60201791 |
May 2000 |
US |
Divisions (1)
|
Number |
Date |
Country |
Parent |
09842579 |
Apr 2001 |
US |
Child |
10222715 |
Aug 2002 |
US |