A laser device, in particular for ophthalmological laser surgery, comprising a laser source (14) for providing laser radiation, controllable scan components (20) for setting a focus position of the laser radiation, measuring components (30) for registering information that is representative of an actual position of the radiation focus, and also a control arrangement (22) controlling the laser source and the scan components. In accordance with the invention, the control arrangement can be set up to bring about the implementation of a test-mode operation of at least some of the scan components with the laser source turned off, in accordance with a predetermined test scan pattern, the test scan pattern representing a plurality of discrete desired focus positions to be traversed in succession, and the control arrangement having been set up to stop, at each of the desired focus positions, the scan movement of the scan components and to ascertain, assigned to each of the desired focus positions, respectively an actual focus position on the basis of the registered information of the measuring components.
