Treatment apparatus for surgical correction of defective eyesight, method of generating control data therefore, and method for surgical correction of defective eyesight

A method for preparing control data for laser based surgical correction of an eyesight defect in a patient's eye, wherein the eye comprises a cornea having an anterior corneal surface and corneal tissue located below the anterior corneal surface, the method comprising:

• determining measurement data on parameters of the eye and defective-eyesight data on the eyesight defect,
• defining a volume on a basis of the measurement data and the defective-eyesight data, wherein the volume is sized such that removal of the volume from the corneal tissue below the anterior corneal surface changes a shape of the anterior corneal surface such that the eyesight defect is corrected or reduced,
• determining a three dimensional (3D) surface to confine the defined volume within the cornea, wherein the 3D surface comprises two surface parts including an anterior surface part and a posterior surface part and determining the control data for the treatment apparatus for the anterior surface part accounting for a spherical contact glass deforming the anterior corneal surface to become spherical wherein the anterior surface part is a paraboloid that is cut while the anterior corneal surface is deformed to be spherical by application of the spherical contact glass and wherein the posterior surface part does not have a constant distance from the anterior corneal surface,
• determining a three-dimensional pattern of target points located in the 3D surface, wherein the 3D surface defines a 3D cut within the cornea, the 3D cut confining the volume located within the cornea, isolating the volume within the cornea, and making the volume extractable from the interior of the cornea, and
• generating a control data set which relates to the three-dimensional pattern for control of a laser device providing the pulsed laser radiation to create the 3d cut.

A planning device for generating control data for a treatment apparatus for surgical correction of an eyesight defect in an eye of a patient, the eye comprising a cornea, wherein:

• the planning device comprises an interface for receiving measurement data on parameters of the eye, and defective-eyesight data on the eyesight defect;
• and
• the planning device is further configured:
• to define a volume on basis of the measurement data and the defective-eyesight data, wherein the volume is sized such that removal of the volume from the corneal tissue below the anterior corneal surface changes a shape of the anterior corneal surface such that the eyesight defect is corrected or reduced;
• to determine a 3D surface to confine the defined volume within the cornea, wherein the 3D surface comprises two surface parts including an anterior surface part and a posterior surface part and wherein the anterior surface part is a paraboloid that is cut while an anterior corneal surface is deformed to be spherical by a spherical contact glass applied to the anterior corneal surface and wherein the posterior surface part does not have a constant distance from the anterior corneal surface;
• to determine a three-dimensional pattern of target points located in the 3D surface, wherein the 3D surface defines a 3D cut within the cornea, the 3D cut confining the volume located within the cornea, isolating the volume within the cornea, and making the volume extractable from the interior of the cornea;
• and
• to generate a control data set which relates to the three-dimensional pattern for control of a laser device providing the pulsed laser radiation to create the 3d cut.

A treatment apparatus for laser based surgical correction of an eyesight defect in a patient's eye, wherein the eye comprises a cornea having an anterior corneal surface and corneal tissue located below the anterior corneal surface, wherein the apparatus comprises:

• a laser device for emitting pulsed laser radiation;
• a focusing device for focusing the pulsed laser radiation to a focus within the cornea;
• a scanning device for directing the focus to target points within the cornea;
• and
• a control device configured to control the scanning device for creating a 3D cut within the cornea, the 3D cut confining a volume located within the cornea, isolating the volume within the cornea, and making the volume extractable from the interior of the cornea, wherein the volume is sized such that removal of the volume from the corneal tissue below the anterior corneal surface changes a shape of the anterior corneal surface such that the eyesight defect is corrected or reduced;
• wherein the control device is further configured to control the scanning device for shifting the focus of the pulsed laser radiation over a three-dimensional pattern of the target points in the cornea, wherein the target points are located in a 3D surface defining the 3D cut and wherein the 3D surface comprises two surface parts including an anterior surface part and a posterior surface part, wherein the anterior surface part is a paraboloid that is cut while the anterior corneal surface is deformed to be spherical by a spherical contact glass applied to the anterior corneal surface and wherein the posterior surface part does not have a constant distance from the anterior corneal surface.