Structured light is readily used to control and investigate microsystems. Dynamic manipulation of microscopic particles of matter has enabled non-contact investigations of a large number of complex physical, biological and chemical systems. In recent years, ever more sophisticated techniques to control microsystems have been developed, shadowing rapid advances in computer technology. This work utilises computational and other signal processing techniques to dynamically control input light fields and modulate the scattered output light fields to improve the specificity of measurements using either optical switching or beam shaping. The aggregate properties of structured light such as linear and angular momentum are changed when scattered from a particle. We present improvements to measurement of signals otherwise hidden in noise or other larger signals by selectively filtering considering the amplitude, phase or wave function symmetry. Measurements are demonstrated using both liquid crystal spatial light modulators and digital micromirror devices. Further challenges that occur in development of these techniques will be discussed as well as their use when applied to specific experiments. We will give an overview of both past successes in measurement of position, force and angular momentum transfer and other current research developments.
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