  Miniaturized optical imaging systems typically utilize 2-dimensional (2D)
actuators to acquire images over a 2D field of view (FOV). Piezoelectric tubes
are most compact, but usually produce sub-millimeter FOVs and are difficult to
fabricate at scale, leading to high costs. Planar piezoelectric bending
actuators (benders) are capable of much larger actuations and are substantially
lower cost, but inadequate for 2D steering. We presented a multi-beam fiber
scanning platform that generated multi-millimeter 2D scans with a 1D actuator
by maximizing the mechanical coupling effect in its orthogonal axis. We further
expanded the FOV by demonstrating mosaiced fields driven with spiral and
cycloid trajectories, where three optical fibers were optimized to resonate
with identical paths in synchronicity. Leveraging optical coherence tomography
with a long coherence length laser, we acquired depth-multiplexed images of
biological samples at 12.6 um resolution. This multi-fold improvement in
scanning coverage and cost-effectiveness promises to accelerate the advent of
piezoelectric optomechanics in compact devices such as endoscopes and headsets,
and miniaturized microscopes at point-of-care.
