A bi-axially accelerating Airy beam for miniaturized light-sheet microscopy

The use of one-dimensional Airy beams in light-sheet microscopy (LSM) allows the generation of thin lightsheets without scanning, and thus have great potential for simplifying multi-photon LSM systems. However, their uni-axial acceleration limits the maximum numerical aperture of the collection objective in order to keep both the active and inactive axes within its depth of field. This issue is particularly pronounced in potential miniaturized LSM implementations, such as those for endomicroscopy or multi-photon neural imaging in freelymoving animals using head-mounted miniscopes. To address this issue, we propose a new method to generate a bi-axially accelerating static Airy light-sheet that illuminates a thin spherical shell within the field-of-view (FOV) of a collection objective. This profile can be engineered to match both the detection objective’s field curvature and FOV. Using an illumination unit that combines GRIN optics with a phase mask that is 3D-printed using 2-photon polymerization, we experimentally demonstrate the validity of the approach, and verify the analytical models.