3D Spatial Focal Control by Arrayed Optofluidic Prisms

A new 3D focal control system composed of arrayed optofluidic prisms is presented. Through dynamic control of the fluid-fluid interface via electrowetting, incoming rays are spatially steered to achieve 3D focal control. Analytical study identifies the prism angle required to obtain a focal point at P
focal
= (f
x
, f
y
, f
z
) located in 3D space. Experimentally, an arrayed system has demonstrated its 3D focal tunability along 0 ≤ f
x
≤ 30, 0 ≤ f
y
≤ 30, and 500 ≤ f
z
≤ ∞ in millimeters. This new lens capability for 3D focal control can be potentially used for tracking eye movement for smart displays, or solar tracking for smart compact concentrated photovoltaic systems.