The invention relates to a process for minimally invasive to non-invasive optical treatment of tissues of the eye and also for diagnosis thereof and to a device for implementing this process. The object underlying the invention is to create a process and a laser arrangement for minimally invasive to non-invasive optical treatment in the interior of the eye, particularly of cases of defective vision, by ablation of tissue, said treatment being distinguished by a hitherto unattained high precision, with possible widths of incision in the range less than 2 mum, without a significant mechanical impairment of the surrounding tissue occurring that has been generated by photodisruption. The process and the arrangement are to be inexpensive and easy to operate. In addition, at the same time the arrangement is to enable a three-dimensional imaging of the tissue. This object is achieved by virtue of a process in which the ablation is effected by focused planar or spatial scanning while adhering to equal, in order of magnitude, focusing-point diameters and point spacings below 5 mum with a radiation within the spectral range from 500 nm to 1200 nm, whereby, by virtue of a pulse duration in the order of femtoseconds and an energy of the individual pulse in the order of nanojoules and below, the destruction of the tissue is substantially limited to the diameter of the point, and permanent changes by virtue of propagation of energy beyond this diameter are avoided. The invention can be applied in opthalmology.