Using photopolymerization to achieve tunable liquid crystal lenses with coaxial bifocals.

Liquid crystal (LC) lenses with circular hole-patterned electrodes possess the excellent capabilities of tunable focal lengths. In this paper, we demonstrate the performance of a specific LC lens with tunable coaxial bifocals (CB) synthesized via photopolymerization of LC cells. The characteristics of tunable CB are clearly exhibited when the voltage applied is continuously increased, eventually disappearing until only one focus is left when significantly higher voltages are applied. We simultaneously demonstrate two types of tunable CB LC lenses fabricated via different photocurable processes and determine their optical functions.