Adaptive optics in laser processing

Adaptive optics are becoming a valuable tool for laser processing, providing enhanced functionality and flexibility for a range of systems. Using a single adaptive element, it is possible to correct for aberrations introduced when focusing inside the workpiece, tailor the focal intensity distribution for the particular fabrication task and/or provide parallelisation to reduce processing times. This is particularly promising for applications using ultrafast lasers for three-dimensional fabrication. We review recent developments in adaptive laser processing, including methods and applications, before discussing prospects for the future. The integration of adaptive optics with laser processing is enhancing the capabilities of laser systems, enabling precision fabrication inside materials, the tailoring of focal intensity for structured and wide-area fabrication, and fine control of the fabrication process. Patrick Salter and Martin Booth from the University of Oxford in the United Kingdom have undertaken a review of how recent developments in adaptive optics are providing advanced control of the laser fabrication process. They show how simple adaptive elements, such as liquid crystal spatial light modulators and digital micromirror devices, which allow for the phase, amplitude, and polarisation of the fabrication beam to be modulated, are providing many possibilities for advanced control of the laser fabrication process, and, as the technology develops further, the range of applications of adaptive optical laser fabrication is likely to expand.