3D Laser Beam Shaping for Manufacturing within Volumes

Over the last two decades, enhanced availability of spatial light modulator (SLM) technology has driven development of numerous beam-shaping techniques, allowing one to sculpt the amplitude, phase, and polarisation of a light beam. By shaping light, some control over its focussing properties is gained, and is thus desirable in laser processing applications where efficiency and distribution of the energy transfer region in laser-material interaction is of great importance. Traditional focussing systems often consist of a Gaussian input beam and conventional lens, resulting in a highly confined focal volume in all three dimensions. While this is ideal for certain applications, others benefit from the extended depth of focus provided by an axicon lens. By shaping and redistributing the incident light to an axicon system, control of the resulting intensity distribution in three dimensions is possible, opening the door for more advanced laser processing techniques.

Whilst numerous intelligent approaches to beam-shaping with SLM technology have been demonstrated over recent years, these often suffer from poor efficiency (of order