Device and process for machining the cornea of a human eye with focused pulsed laser radiation
A device for generating at least one continuous slit-like incision ( 42 ) from the posterior surface ( 48 ) as far as the anterior surface ( 46 ) of the cornea ( 44 ) of an eye, comprising a laser device for generating at least one part of the incision with focused pulsed laser radiation, the laser device including controllable components for setting the location of the focus, a control computer for controlling these components, and also a control program for the control computer. The control program contains instructions that are designed to bring about, upon execution by the control computer, the generation of at least one part of the incision ( 42 ) originating from the posterior surface ( 48 ) of the cornea, the cross-sectional contour of the incision—when observed in the direction from the anterior surface to the posterior surface—deviating from a straight line ( 60 ) perpendicular to the surface of the eye.
1. A method for generating at least one incision in a cornea of a human eye, the method comprising:
generating, with laser radiation from a laser device, a slit-like incision from a posterior surface to an anterior surface of the cornea, the incision forming a slit in an x-y plane in the cornea, the slit in the x-y plane being substantially rectilinear and arranged along a circular line substantially concentric with the pupil of the eye, a width of the slit in the x-y plane being a few millimeters sized to introduce a medical instrument; and
generating, with the laser radiation from by the laser device, the slit-like incision with a cross-sectional contour in an x-z cross-section, the cross-sectional contour comprising a posterior portion, a middle portion connected to the posterior portion, and an anterior portion connected to the middle portion, the posterior portion angled from the middle portion towards the pupillary center, the middle portion substantially perpendicular to the surface of the eye, and the anterior portion angled from the middle portion away from the pupillary center, wherein the posterior portion, the middle portion, and the anterior portion are substantially rectilinear.
2. The method according to claim 1 , wherein the cross-sectional contour of the incision exhibits at least one bend.
3. The method according to claim 1 , wherein the width of the slit is substantially constant from the posterior surface to the anterior surface.
4. The method according to claim 1 , wherein the width of the slit increases from the posterior surface to the anterior surface.
5. The method according to claim 1 , wherein the width of the slit decreases from the posterior surface to the anterior surface.
6. The method according to claim 1 , further comprising:
generating, with the laser radiation from the laser device, an additional slit-like incision with a slit arranged along the circular line.
7. The method according to claim 1 , further comprising:
generating, with the laser radiation from the laser device, an additional slit-like incision with a slit arranged along another circular line substantially concentric with the pupil of the eye.
8. The method according to claim 1 , wherein the laser radiation possesses pulse durations of less than 1 picosecond.