In this Review, we survey recent developments in the emerging field of high-speed variable-
z-focus optical elements, which are driving important innovations in advanced imaging and …

We report a noninvasive strategy for electrically stimulating neurons at depth. By delivering
to the brain multiple electric fields at frequencies too high to recruit neural firing, but which …

Tunable liquid lenses with controllable focal length attract much attention from many
researchers due to the unique advantages of strong adjustability, low power consumption …

We demonstrate the implementation of a compact tunable-focus liquid lens suitable for
adaptive eyeglass application. The lens has an aperture diameter of 32 mm, optical power …

Metasurface‐based lenses (metalenses) offer specific conceptual advantages compared to
ordinary refractive lenses. For example, it is possible to tune the focal length of a metalens …

A large aperture tunable lens based on liquid crystals, which is considered for near-to-eye
applications, is designed, built, and characterized. Large liquid crystal lenses with high …

We describe a system which corrects dynamically for the focus of the real world surrounding
the near-eye display of the user and simultaneously the internal display for augmented …

Multi-motor configuration of multi-DOF (degree of freedom) optical system is a major source
of redundant structure, putting a limitation on the simple and miniaturized design. Thus, a …

Flat glass is clear while frosted glass with a microrough surface appears translucent by light
scattering. Motivated by this optical surface scatterer, a transparent soft media with …

We experimentally demonstrate a highly efficient, broadband linear polarization converter
functioning at terahertz frequencies. The linear polarization converter is composed of three …