Adaptive optimisation of a generalised phase contrast beam shaping system

• DOI: 10.1016/j.optcom.2014.12.059
• Publication Date: 2014-12-26T16:39:33Z
• Authors: F. Kenny; F.S. Choi; J. Glückstad; M.J. Booth
• Keywords: Phase contrast; Spatial light modulators; Physical and Theoretical Chemistry; Electrical and Electronic Engineering; Adaptive optics; 01 natural sciences; Atomic and Molecular Physics, and Optics; Article; Electronic, Optical and Magnetic Materials; 0104 chemical sciences

The generalised phase contrast (GPC) method provides versatile and efficient light shaping for a range of applications. We have implemented a generalised phase contrast system that used two passes on a single spatial light modulator (SLM). Both the pupil phase distribution and the phase contrast filter were generated by the SLM. This provided extra flexibility and control over the parameters of the system including the phase step magnitude, shape, radius and position of the filter. A feedback method for the on-line optimisation of these properties was also developed. Using feedback from images of the generated light field, it was possible to dynamically adjust the phase filter parameters to provide optimum contrast.