Three-dimensional adaptive microscopy using embedded liquid lens.

We report on the compact optical design of a high-resolution 3D scanning microscope with adaptive optics capability for refocusing with no moving parts designed for clinical research. The optical aberrations arising from refocusing are compensated for as part of the multiconfiguration optical design process. The lateral scanning is provided by a scanning mirror, and the depth scan is provided by an adaptive liquid lens embedded within the microscope as an integrated component of a custom optical design. The microscope achieves a performance of 250 lp/mm-a tenfold increase in performance over a liquid lens used as a stand-alone optical element. Results show that the optical design provides invariant modular transfer function over a 2 mm x 2 mm x 2 mm imaging volume, fully compensating (i.e., diffraction limited) for dynamic aberrations contributed by the scanning, the variation in the shape of the liquid lens, and the change in spherical aberration with depth in a slab of average index of refraction of skin. This design can find applications in biomedical imaging, white light interferometry for surface roughness measurements, and other 3D imaging systems.