Electrically Tunable Polymer Stabilized Chiral Ferroelectric Nematic Liquid Crystal Microlenses

Abstract

Tunable optical lenses are in great demand in modern technologies ranging from augmented and virtual reality to sensing and detection. In this work, electrically tunable microlenses based on a polymer‐stabilized chiral ferroelectric nematic liquid crystal are described. The power of the lens can be quickly (within 5 ms) varied by ≈500 diopters by ramping an in‐plane electric field from 0 to 2.5 V µm−1. Importantly, within this relatively low‐amplitude field range, the lens is optically isotropic; thus, its focal length is independent of the polarization of incoming light. This remarkable performance combines the advantages of electrically tuned isotropic lenses and the field‐controlled shape of the lens, which are unique properties of chiral ferroelectric nematic liquid crystals and have no counterpart in other liquid crystals. The achieved lens performance represents a significant step forward as compared to liquid lenses controlled by electrowetting and opens new possibilities in various applications such as biomimetic optics, security printing, and solar energy concentration.

Evaluation of polar alignment structure and surface anchoring energy in ferroelectric nematic liquid crystals by renormalized transmission spectroscopic ellipsometry

“…The FNLC material used in this study is FNLC-919 (Merck), which was reported to exhibit the FNLC phase at RT (20 °C) 17) and has been utilized in fundamental and applied research fields. 29) The initial value of the birefringence of FNLC-919 was set as are determined for adjacent wavelengths by the procedure described above, where the ( ) l Dn can be well approximated by Cauchy dispersion and its coefficients were also determined at the same time. Searching for the multivariate that minimizes the difference between measured and simulated values with respect to ( ) l D and ( ) l Y , based on the polytope method as the best method for multivariate analysis, finally j t can be determined.…”