GoPro, Inc.
Tunable polymer dispersed liquid crystal grin lens

Abstract:

A camera system includes an image sensor assembly and a tunable optical element. The tunable optical element is a gradient index (GRIN) lens created from a polymer dispersed liquid crystal and a coupled control element. The GRIN lens is tunable by applying an electric field to the optical element via a control element. The control element applies a voltage differential to the optical element inducing an electric field which changes the polarization of the PDLC within the optical element. The electrodes of the control element can include sheet resistors with a radially dependent voltage drop. The refractive index of the GRIN lens is dependent on the polarization of the liquid crystals within the optical element. Applying the electric field to the tunable element changes the optical properties of the grating.