A planning device for generating control data for a treatment apparatus for cornea transplantation, said apparatus using a laser device to isolate, by at least one cut surface (22, 23) in the cornea, a corneal volume, which corneal volume is to be removed from surrounding cornea, and to isolate, by at least one cut surface in the transplantation material, a transplant from a surrounding transplantation material, which transplant is to be inserted into the cornea, wherein the planning device - comprises an interface for supplying measurement data relating to parameters of the cornea, and - computing means for defining a corneal cut surface (22, 23) on the basis of the measurement data, which corneal cut surface (22, 23) confines the corneal volume within the cornea and below a front face of the cornea, wherein said computing means further determine a transplant cut surface, which transplant cut surface depends on the defined corneal cut surface (22, 23) and confines the transplant, and said computing means generate control data sets for the corneal cut surface (22, 23) and the transplant cut surface to control the laser device, wherein the respective cut surfaces can be produced by the laser device when using the control data sets, so as to isolate the corneal volume and the transplant and to make them removable, as well as to make the transplant transplantable, - wherein the computing means, when determining the transplant cut surface, cause a deviation between the corneal volume and the transplant, which deviation depends on a predetermined change in refraction, so as to additionally achieve a correction of eyesight defects by the transplantation, such that the transplant, once inserted, has a certain refractive effect together with the remaining refractive elements of the patient's eye to modify an initial pre-transplantation refraction. - comprises an interface for supplying measurement data relating to parameters of the cornea, and - computing means for defining a corneal cut surface (22, 23) on the basis of the measurement data, which corneal cut surface (22, 23) confines the corneal volume within the cornea and below a front face of the cornea, wherein said computing means further determine a transplant cut surface, which transplant cut surface depends on the defined corneal cut surface (22, 23) and confines the transplant, and said computing means generate control data sets for the corneal cut surface (22, 23) and the transplant cut surface to control the laser device, wherein the respective cut surfaces can be produced by the laser device when using the control data sets, so as to isolate the corneal volume and the transplant and to make them removable, as well as to make the transplant transplantable, - wherein the computing means, when determining the transplant cut surface, cause a deviation between the corneal volume and the transplant, which deviation depends on a predetermined change in refraction, so as to additionally achieve a correction of eyesight defects by the transplantation, such that the transplant, once inserted, has a certain refractive effect together with the remaining refractive elements of the patient's eye to modify an initial pre-transplantation refraction.