Process optimization and performance analysis of an electrostatically actuated varifocal liquid lens

A new type of varifocal liquid lens actuated by electrostatic parallel plates is presented and the main technological steps involved in the fabrication process are discussed. The influences of the membrane material, the electrode size and the optical diameter on the optical performance of the lens are characterized using wave-front measurements giving basic design rules for the device performance optimization. Optical powers of 13m
⁻¹
at 20V and 11m
⁻¹
at 13V are measured on lenses with optical diameters of 3mm and 1.5mm respectively. When placed ahead of a 3Mp camera module, the variable-focus liquid lens permits to focus on the different parts of a scene by changing the applied voltage.