Focus-tunable lens with gravity-compensation. Wavefront analysis

Abstract

An electrically-addressed focus-tunable lens (FTL) enables fine, continuous, and dynamic power adjustment across a range of diopters. This lens encloses an optical fluid within a sealed container with an elastic membrane. An electromagnetic actuator applies pressure to the container, altering the curvature of the lens. This study investigates the optical performance of a gravity-compensated FTL (Optotune EL-16-40-GTC-VIS-5D) in terms of the addressed optical power and measured wavefront error, in both horizontal and vertical lens orientation. The results were compared with two standard, uncompensated models from the same manufacturer. All the analysed FTLs demonstrated excellent optical power performance regardless of orientation. The gravity-compensated FTL effectively corrected vertical coma in the upright orientation, but induced greater astigmatism compared to the standard models. These findings provide valuable insights for vision testing and adaptive optics applications.