In an embodiment, a laser apparatus comprises a semiconductor laser (22), e.g., of the VECSEL type, for generating pulsed laser radiation having a pulse duration in the femtosecond range or shorter and having a pulse repetition rate of at least 100 MHz； a selector (54) for selecting groups (60) of pulses from the laser radiation, each pulse group comprising a plurality of pulses at the pulse repetition rate, wherein the pulse groups are time-displaced by at least 500 ns； a scanner device for scanning a focal point of the laser radiation； a controller for controlling the scanner device based on a control program including instructions that, when executed by the controller, bring about the creation of a LIOB-based photodisruption for each pulse group in a target material, e.g. human eye tissue.
