Seventh-order wavefront modulation with a gravity-neutral optofluidic deformable phase plate

Abstract. A 63-electrode optofluidic refractive wavefront modulator enabling spatial frequency correction up to the seventh radial Zernike order, the highest spatial order ever achieved with a refractive dynamic wavefront modulator, is presented. The modulator is designed so that aberration correction performance is nearly identical in both horizontal and vertical orientations, virtually eliminating the gravity-induced parasitic surface deformations typical for optofluidic devices. With 55 of its electrodes located within the 1-cm clear pupil, the modulator offers the versatility of continuous face-sheet deformable mirrors within a compact, high efficiency, and transmissive device. Using a fluidic interfacing method based on wafer-level 3D micro-structuring of glass, the modulator is only 0.86-mm-thick, facilitating the cascading of multiple modulators within close proximity. We demonstrate a bi-directional stroke of more than 13 λ, and replications of Zernike mode shapes up to the seventh radial order with high fidelity, representing a significant leap in the performance of ultra-miniaturized refractive wavefront modulators.