A planning device generating control data for a treatment apparatus (1) for cornea transplantation is described, said apparatus using a laser device (4) to separate a corneal volume (21), which is to be removed, from the surrounding cornea (17) by at least one cut surface in the cornea and to separate a transplant, which is to be inserted into the cornea, from a surrounding transplantation material by at least one cut surface in the transplantation material, wherein the planning device - comprises an interface (29) supplying measurement data relating to parameters of the cornea (17), - means for defining a corneal cut surface (22, 23) which confines the corneal volume (21) to be removed, which means for defining the corneal cut surface (22, 23) access the measurement data, and - computing means determining a transplant cut surface by using the transplantation material data and depending on the defined corneal cut surface (22, 23), which transplant cut surface confines the transplant, and said computing means generating one control data set each for the corneal cut surface (22, 23) and the transplant cut surface to control the laser device (4), wherein the respective cut surfaces can be produced by the laser device 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.
