A laser clock signal generator for controlling a laser beam generator to generate pulse laser radiation is provided. The laser clock signal generator includes a clock signal specification input arranged to receive an external clock specification signal, a basic clock signal generator configured to generate a basic clock signal based on the external clock specification signal and output the basic lock signal at a clock signal output to the laser beam generator, and a controller configured to control the basic clock generator, for example, to be synchronized with the external clock specification signal. The laser clock signal generator also includes an overclocking protector arranged between the basic clock generator and the clock signal output.