Device for defining a flap geometry

1. A device for defining a flap geometry of a flap for laser treatment of a human eye, comprising:

a laser source of a cutting laser, the laser source configured to generate a laser beam having pulse durations in the femtosecond range, the laser beam suitable for generating an optical breakdown in a human cornea;

a scanner unit of the cutting laser, the scanner unit configured to control a focus of the laser beam in a transverse direction and in a longitudinal direction; and

a control unit programmed to:

evaluate ablation profile data of an ablation profile for a laser ablation treatment of the cornea, the ablation profile describing ablation of the cornea by an ablation laser, the evaluating comprising determining a diameter of the ablation profile;

define the flap geometry based on the evaluation according to:

a diameter of the flap based on the diameter of the ablation profile that describes ablation of the cornea;

a defined safety margin stored with the ablation profile, such that in top view a shortest distance between an outer edge of the ablation profile and an outer edge of the flap at each location amounts to at least the safety margin; and

a position of a hinge of the flap such that a shortest distance from the hinge to an outer edge of the ablation profile amounts to at least the safety margin; and

instruct the scanner unit of the cutting laser to control the focus of the laser beam to cut the flap with the flap geometry in a cornea of the human eye.

2. The device of claim 1 , wherein:

evaluating the ablation profile data comprises determining a position of the ablation profile with respect to the eye to be treated; and

defining the flap geometry comprises defining a position of the flap with respect to the eye to be treated.

3. The device of claim 1 , wherein:

evaluating the ablation profile data comprises determining an orientation of the ablation profile with respect to the eye to be treated; and

defining the flap geometry comprises defining an orientation of the flap with respect to the eye to be treated.

4. The device of claim 3 , wherein defining the orientation of the flap comprises defining a position of a hinge of the flap with respect to the eye to be treated.

5. The device of claim 1 , wherein:

evaluating the ablation profile data comprises determining an axis along which the ablation profile has the greatest diameter; and

defining the flap geometry comprises defining an orientation of the hinge of the flap parallel to the axes.

6. The device of claim 1 , wherein:

evaluating the ablation profile data comprises determining an axis of mirror symmetry of the ablation profile; and

defining the flap geometry comprises defining an orientation of a hinge of the flap perpendicular to the axis of mirror symmetry.

7. The device of claim 1 , wherein:

defining the flap geometry is performed in consideration of a corneal thickness or at least one curvature radius of the cornea of the eye to be treated.

8. The device of claim 1 , further comprising:

an input interface for reading in the ablation profile data.

9. The device of claim 1 , wherein the control unit is further programmed to determine flap geometry data based on the defined flap geometry.

10. The device of claim 9 , further comprising:

an output interface for outputting the flap geometry data.

11. The device of claim 1 wherein the outer edge of the flap exceeds the outer edge of the ablation profile by the safety margin.