LASER PULSE CASCADE

An illumination module of a wafer inspection system including: an illumination source providing ultraviolet illumination with wavelengths below 300 nm; a pulse cascader, optically coupled to the illumination source to receive the ultraviolet illumination, which pulse cascade including a chain of a plurality of loops, each loop including: a loop input and a loop output, a first loop output optically coupled to a loop input of a subsequent loop in the chain; and a delay line having: a delay line input optically coupled to the loop input; and a delay line output, the delay line configured to output a delay line light output, from the delay line output, including an image of light received at the delay line input, after a time delay from a time of receipt of light received at the delay line input; and a splitter configured to receive light at a splitter input and output a first portion of the light from the loop through a loop output and to pass a second portion of the light to the delay line input.