  Phase-only spatial light modulators can be employed to structure laser light
in complex three dimensional focusing patterns, with a variety of applications.
While spatial light modulators have typical refresh frequencies of tens of Hz,
the computation time of three dimensional holograms ranges between a few
seconds and a few minutes, therefore limiting the use of the maximum refresh
rate of spatial light modulators to either pre-calculated sequences of high
quality holograms, or low quality holograms only for real time update. Here, we
propose the implementation of a recently developed compressed sensing
Gerchberg-Saxton algorithm on a consumer graphical processor allowing the
generation of high quality holograms at video rate.
