Adaptive optics (AO) normally concerns the feedback correction of phase aberrations. Such correction has been of benefit in various optical systems, with applications ranging in scale from astronomical telescopes to super-resolution microscopes. Here we extend this powerful tool into the vectorial domain, encompassing feedback correction of both polarisation and phase. This technique is termed vectorial adaptive optics (V-AO). We show that V-AO can be implemented using sensor feedback, where an imaging polarimeter is used as the analog to the wavefront sensor used in phase AO. Alternatively, correction can be performed indirectly using so-called “sensorless” AO, which for phase AO does not employ a wavefront sensor but uses indirect optimization of the optical performance. Sensorless V-AO takes a similar approach optimizing the vectorial state through indirect optimization in the focal plane. An intermediate quasi-sensorless V-AO method is also shown. We validate improvements in both vector field state and the focal quality of an optical system, through correction for commonplace vectorial aberration sources, ranging from objective lenses to biological samples. This technique pushes the boundaries of traditional scalar beam shaping with feedback by providing control of extra vectorial degrees of freedom, which also paves the way for next generation AO functionality by manipulating the complex vectorial field.
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