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In order to obtain 3D information of an object, laser-scanning techniques like confocal microscopy require a scan in three dimensions. The axial scan is commonly achieved by mechanical translation of the objective or the object. However, inertia is a problem, which limits the achievable scan rates and leads to motion artifacts. The usage of adaptive optical elements bears the potential to overcome these limitations. Adaptive lenses have been applied in different kinds of microscopes to perform the axial scan without the need for any mechanical translation. In this contribution, we introduce a novel bi-actor adaptive lens that enables to manipulate both the focus position and the specimen-induced spherical aberrations that occur in deep tissue applications as well as systematic scan induced aberrations. To achieve the desired lens behavior against environmental influences and hysteresis effects an in-situ monitoring based on digital holography or partitioned aperture wavefront sensing are applied. Experiments on Zebrafish and on phantom samples prove the capabilities of our approach Beside axial scanning adaptive lateral scanning is also addressed: Lateral scans are often realized using galvo scanner. Although this approach works well, it requires a folded beam path resulting in bulky setups. We introduce piezo-actuated adaptive prisms as a suitable alternative that enables an optical setup in in-line transmissive configuration instead. With this device wavefront tilts of up to ±7° can be induced, enabling lateral scanning. We show characterization measurements and first proof of concept applications on the adaptive prisms.
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