Device for measuring wave fronts generated by a lens (4) for an eye, with a radiation source (14) for emitting test radiation (12) to be directed at the lens (4) and a sensor device (26) for detecting wave fronts of incident test radiation after interaction with the lens, wherein the sensor device scans the test radiation (20) after interaction with the lens (4) at a scanning frequency which is at least equal in size to the frequency at which changes in wave fronts occur in the test radiation (20) after interaction with the lens (4).