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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.
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This content will become publicly available on January 1, 2026
Electrically Tunable Chiral Ferroelectric Nematic Liquid Crystal Reflectors
Abstract Manipulating light is an important area of optical research and development. To that end, tunable dichroic devices in which the reflectivity at differing wavelengths can be adjusted, are particularly valuable. This work is motivated by recent studies of the optical properties of chiral ferroelectric nematic liquid crystals (FNLCs). Here electro‐optical studies are presented on two room temperature, FNLC materials that demonstrate electrically tunable reflectivity when subject to a field below 0.2 V µm−1. Moreover, under appropriate conditions, the reflectivity can also be electrically (and reversibly) tuned (without change of color) from 0% to 40%. Reversible, low voltage tunable mirrors, having miniscule power consumption and operable around ambient temperature are expected to be useful in diverse applications ranging from energy‐saving, smart windows to virtual reality interfaces.
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- Award ID(s):
- 2210083
- PAR ID:
- 10609440
- Publisher / Repository:
- Wiley
- Date Published:
- Journal Name:
- Advanced Functional Materials
- Volume:
- 35
- Issue:
- 3
- ISSN:
- 1616-301X
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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