Claims
- 1. A method of controlling a laser system for removing tissue from a region of the cornea that creates a laser spot of a size and with center with a location on a cornea with a perpendicular axis of treatment, comprising the steps of:
(a) setting the spot size to between 10% and 90% of the size of the region; and (b) moving the spot center location along the cornea to at least one location away from the axis of treatment.
- 2. The method of claim 1 for providing laser polishing, wherein said step of moving the spot location further comprises the steps of:
(a) arbitrarily oscillating the spot center location within a dithering region with a diameter smaller than the maximum width of the laser spot.
- 3. The method of claim 1 for providing laser polishing, wherein said step of moving the spot location further comprises the steps of:
(a) moving the spot center location along the periphery of a dithering region with a maximum width smaller than the maximum width of the laser spot.
- 4. The method of claim 1 for providing laser polishing, wherein said step of moving the spot location further comprises the steps of:
(a) moving the spot center location along the periphery of a circular dithering region with a diameter smaller than the maximum width of the laser spot.
- 5. The method of claim 1 for providing laser polishing, wherein said step of moving the spot location further comprises the steps of:
(a) moving the spot center location along at least one axis perpendicular to the axis of treatment.
- 6. The method of claim 1 for correcting hyperopia, wherein said step of moving the spot location further comprises the steps of:
(a) moving the spot center location along a first circle; (b) changing the spot size; and (c) moving the spot center location along a second circle with a center corresponding to the center of said first circle.
- 7. The method of claim 1 for correcting astigmatism, wherein said step of moving the spot location further comprises the steps of:
(a) moving the spot center location along a line; (b) changing the spot size; and (c) moving the spot center location along a said line.
- 8. The method of claim 1 for correcting astigmatism, wherein said step of moving the spot location further comprises the steps of:
(a) moving the spot center location along an arc; (b) changing the spot size; and (c) moving the spot center location along a said arc.
- 9. A method of controlling a laser system for removing tissue from a region of a cornea in which tissue is to be removed to achieve a desired corneal profile of the region for correction of vision, the region having a total treatment area with a size, and the region having a center of treatment on the cornea, where the laser system creates a laser spot with a laser spot area of a variable size on the cornea, with a maximum width, and with a center at a variable location on the cornea, and with a perpendicular axis of treatment, comprising the steps of:
(a) setting the spot size to a first size of between 10% and 90% of the size of the total treatment area of the region in which tissue is to be removed; (b) after step (a), moving the spot center location along the cornea to at least one location away from the axis of treatment; (c) ablating the cornea with the laser spot by firing the laser system; (d) repeating steps (b) and (c) for a plurality of laser system firings; (e) after steps (a) through (d), setting the spot size to a second size different from the first size but smaller than 90% of the size of the total treatment area; (f) after step (e), moving the spot center location along the cornea to at least one location away from the axis of treatment; (g) ablating the cornea with the laser spot by firing the laser system; (h) repeating steps (f) and (g) for a second plurality of laser system firings; and (i) repeating steps (e) to (h) to perform a course of treatment upon the region of the cornea by varying the size and location of the laser spot according to the tissue to be removed from the region of the cornea to achieve the desired corneal profile, whereby the formation of large ridges in the region of the cornea is avoided.
- 10. The method of claim 9 for providing laser polishing, wherein said step of moving the spot location further comprises the steps of:
(a) arbitrarily oscillating the spot center location within a dithering region with a diameter smaller than the maximum width of the laser spot.
- 11. The method of claim 9 for providing laser polishing, wherein said step of moving the spot location further comprises the steps of:
(a) moving the spot center location along the periphery of a dithering region with a maximum width smaller than the maximum width of the laser spot.
- 12. The method of claim 9 for providing laser polishing, wherein said step of moving the spot location further comprises the steps of:
(a) moving the spot center location along the periphery of a circular dithering region with a diameter smaller than the maximum width of the laser spot.
- 13. The method of claim 9 for providing laser polishing, wherein said step of moving the spot location further comprises the steps of:
(a) moving the spot center location along at least one axis perpendicular to the axis of treatment.
- 14. The method of claim 9 for correcting hyperopia, wherein said step (b) further comprises the step of:
moving the spot center location along a first circle; and wherein said step (f) further comprises the step of:
moving the spot center location along a second circle with a center corresponding to the center of said first circle.
- 15. The method of claim 9 for correcting astigmatism, wherein said step (b) further comprises the step of:
moving the spot center location along a line, and wherein said step (f) further comprises the step of:
moving the spot center location along a said line.
- 16. The method of claim 9 for correcting astigmatism, wherein said step (b) further comprises the step of:
moving the spot center location along an arc; and wherein said step (f) further comprises the step of:
moving the spot center location along said arc.
- 17. A method of controlling a laser system for removing tissue from a region of a cornea in which tissue is to be removed to achieve a desired corneal profile of the region for correction of vision, the region having a total treatment area, the region having a center of treatment on the cornea, comprising the steps of:
(a) providing a laser beam having a suitable wavelength for ablation of corneal tissue; (b) imaging with an optical system a laser spot on the cornea of a variable size on the cornea and at a variable location on the cornea, the laser spot being imaged on the cornea having a laser spot area and the laser spot having a center; (c) directing the optical system to perform a course of treatment upon the region of the cornea by varying the size and location of said laser spot according to the tissue to be removed from the region of the cornea to achieve the desired corneal profile; (d) limiting the size of said laser spot such that during the course of treatment, the laser spot achieves a maximum spot area of between approximately 10% and 90% of the total treatment area of the region in which tissue is to be removed; and (e) directing said optical system to move the center of the laser spot over a portion of the region in which tissue is to be removed to at least one location on the cornea away from the center of treatment of the region of the cornea, whereby the formation of large ridges in the region of the cornea is avoided, and wherein the laser spot area on the cornea changes at least once during the course of treatment.
- 18. A method for controlling a laser system for removing material from a region of an object, the laser system creating a profiled laser beam having a profiled beam size with a beam center on the object, and with an axis of treatment, the method comprising the steps of:
(a) setting the profiled beam size in a range from about 10 and 70% of the size of the region; and (b) moving the beam center along the object to at least one location away from the axis of treatment.
- 19. The method of claim 18, wherein the step of moving the beam center further comprises the steps of:
(a) scanning the beam center along the object in a random or pseudo-random pattern so as to produce a series of overlapping ablations.
- 20. The method of claim 18, wherein the step of moving the beam center further comprises the steps of:
(a) scanning the beam center while the beam center remains offset from the ablation center so as to effect a transition zone surrounding the region.
- 21. The method of claim 18, wherein the step of moving the beam center further comprises the steps of:
(a) scanning the beam center location in a rotational pattern while the profiled beam size is smaller than a maximum beam size.
- 22. The method of claim 18, wherein the step of moving the beam center location further comprises the steps of:
(a) scanning the beam center location over the object along a cylinder axis.
- 23. The method of claim 18, the method effecting a treatment for hyperopia, wherein the step of moving the beam center further comprises the steps of:
(a) rotationally scanning the beam center along a first annular band separated from the axis of treatment by a displacement amount; (b) changing the profiled beam size; and (c) varying the displacement amount and rotationally scanning the beam center along a second annular band about the axis of treatment.
- 24. The method of claim 18, the method effecting a treatment for astigmatism, the method comprising:
(a) scanning the beam center location along a line; (b) changing the profiled beam size; and (c) scanning the beam center location along the line.
- 25. The method of claim 18, the method effecting a treatment for astigmatism, the method comprising:
(a) scanning the beam center location along an arc; (b) changing the profiled beam size; and (c) scanning the beam center location along the arc.
- 26. A method for controlling a laser system for removing tissue from a region of a cornea in which tissue is to be removed to effect a desired change in corneal shape of the region for correction of vision, the region having an ablation center and a total treatment area on the cornea, where the laser system creates a laser beam with a beam profile area of a variable size on the cornea with a maximum cross-sectional dimension and with a profiled beam center at a variable location on the cornea, and with an axis of treatment, the method comprising the steps of:
(a) setting the profiled beam size to a first size in a range from about 10% to about 70% of the size of the total treatment area of the region; (b) after step (a), moving the beam center location along the cornea to at least one location away from the axis of treatment; (c) ablating the cornea with the profiled laser beam by pulsing the laser system; (d) repeating steps (b) and (c) for a plurality of laser system pulses; (e) after steps (a) through (d), setting the profiled beam size to a second size different from the first size but smaller than about 70% of the size of the total treatment area; (f) after step (e), moving the beam center location along the cornea to at least one location away from the axis of treatment; (g) ablating the cornea with the profiled beam by pulsing the laser system; (h) repeating steps (f) and (g) for a second plurality of laser system pulses; and (i) repeating steps (e) to (h) to perform a pattern of treatment upon the region of the cornea by varying the profiled beam size and beam center location according to the tissue to be removed from the region of the cornea to effect the desired change in corneal shape of the region.
- 27. The method of claim 26, wherein the steps of moving the beam center further comprises the steps of:
(a) scanning the beam center along the object in a random or pseudo-random pattern so as to produce a series of overlapping ablations.
- 28. The method of claim 26, wherein the steps of moving the beam center further comprises the steps of:
(a) scanning the beam center while the beam center remains offset from the ablation center so as to effect a smooth transition zone surrounding the region.
- 29. The method of claim 26, wherein the steps of moving the beam center location further comprise the steps of:
(a) scanning the beam center location in a rotational pattern while the profiled beam size is smaller than a maximum beam size.
- 30. The method of claim 26, wherein the steps of moving the beam center location further comprises the steps of:
(a) scanning the beam center location over the object along a cylinder axis.
- 31. The method of claim 26, the method effecting a treatment for hyperopia, wherein step (b) further comprises the step of:
(a) rotationally scanning the beam center along a first annular band centered at an axis of rotation; and wherein step (f) further comprises the step of:
(a) rotationally scanning the beam center along a second annular band centered at the axis of rotation.
- 32. The method of claim 26, the method effecting a treatment for astigmatism, wherein step (b) further comprises the step of:
(a) scanning the beam center location along a line; and wherein step (f) further comprises the step of:
(a) scanning the beam center location along the line.
- 33. The method of claim 26, the method effecting a treatment for astigmatism, wherein step (b) further comprises the step of:
(a) scanning the beam center location along an arc; and wherein step (f) further comprises the step of:
(a) scanning the beam center location along the arc.
- 34. A method of controlling a laser system for removing tissue from a region of a cornea in which tissue is to be removed to effect a desired change in corneal shape of the region for correction of vision, the region having a total treatment area, the region having a center of treatment on the cornea, the method comprising the steps of:
(a) providing a laser beam having a suitable wavelength for ablation of corneal tissue; (b) imaging with an optical system a laser beam on the cornea of a variable size on the cornea and at a variable location on the cornea, the laser beam being imaged on the cornea having a profiled beam area and the profiled beam having a center; (c) directing the optical system to perform a course of treatment upon the region of the cornea by varying the size and location of said profiled beam according to the tissue to be removed from the region of the cornea to achieve the desired corneal profile; (d) limiting the size of said profiled beam such that during the course of treatment, the profiled beam achieves a maximum spot area of between approximately 10% and 70% of the total treatment area of the region in which tissue is to be removed; and (e) directing said optical system to move the center of the laser spot over a portion of the region in which tissue is to be removed to at least one location on the cornea away from the center of treatment of the region of the cornea, wherein the laser spot area on the cornea changes at least once during the course of treatment.
- 35. A method for controlling a laser system for removing material from a region of a cornea, the laser system creating a profiled laser beam having a profiled beam size with a beam center on the cornea, and with an axis of treatment, the method comprising the steps of:
(a) setting the profiled beam size in a range from about 10 and 70% of the size of the region; and (b) moving the beam center along the cornea to at least one location away from the axis of treatment.
- 36. The method of claim 18, wherein the object comprises a cornea, and further comprising ablating a portion of the cornea with the profiled laser beam.
- 37. The method of claim 18, wherein the object comprises a polymer, and further comprising ablating a portion of the polymer with the profiled laser beam.
- 38. The method of claim 18, wherein the object comprises a resin, and further comprising ablating a portion of the resin with the profiled laser beam.
- 39. The method of claim 18, wherein the object comprises polymethylmethacrylate, and further comprising ablating a portion of the polymethyhnethacrylate with the profiled laser beam.
CROSS-REFERENCES TO RELATED APPLICATIONS
[0001] This application is a continuation of, and claims priority from U.S. patent application Ser. No. 09/730,072 filed Dec. 5, 2000, which is a continuation of co-pending U.S. patent application Ser. No. 08/968,380, filed Nov. 12, 1997, which is a continuation of U.S. patent application Ser. No. 08/058,599, filed May 7, 1993, now abandoned, the full disclosures of which are incorporated herein by referenced in their entirety.
Continuations (3)
|
Number |
Date |
Country |
Parent |
09730072 |
Dec 2000 |
US |
Child |
09923863 |
Aug 2001 |
US |
Parent |
08968380 |
Nov 1997 |
US |
Child |
09730072 |
Dec 2000 |
US |
Parent |
08058599 |
May 1993 |
US |
Child |
08968380 |
Nov 1997 |
US |