Holographic optical engine (HolOE)

Holographic beam shaping achieved by exploiting the rewritable capability of a spatial light modulator (SLM) displaying a
computer-generated hologram (CGH) is very useful in a variety of applications, especially material laser processing [1].
Although it provides high-processing throughput and high light-use efficiency, the accuracy of the beam shaping is degraded
according to static and dynamic imperfections in the optical system. In order to compensate the static imperfections, a
method that performs the optimization of the CGH in the optical system, called as an in-system optimization, was developed
[2, 3]. A further method that allowing it to dynamically compensate for unknown and sudden disturbances for continuously
optimizing a CGH during laser processing was developed [4]. Recently, it was extended to three-dimensionally focused
beams [5] ...