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
- PAR ID:
- 10513757
- Editor(s):
- Khoo, Iam Choon
- Publisher / Repository:
- SPIE
- Date Published:
- Journal Name:
- Proc. SPIE 12658, Liquid Crystals XXVII
- ISBN:
- 9781510665309
- Page Range / eLocation ID:
- 30
- Format(s):
- Medium: X
- Location:
- San Diego, United States
- Sponsoring Org:
- National Science Foundation
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Abstract 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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Khoo, Iam Choon (Ed.)Nematic liquid crystals exhibit nanosecond electro-optic response to an applied electric field which modifies the degree of orientational order without realigning the molecular orientation. However, this nanosecond electrically-modified order parameter (NEMOP) effect requires high driving fields, on the order of 108 V/m for a modest birefringence change of 0.01. In this work, we demonstrate that a nematic phase of the recently discovered ferroelectric nematic materials exhibits a robust and fast electro-optic response. Namely, a relatively weak field of 2×107 V/m changes the birefringence by ≈ 0.04 with field-on and -off times around 1 μs. This microsecond electrically modified order parameter (MEMOP) effect shows a greatly improved figure of merit when compared to other electro-optical switching modes in liquid crystals, including the conventional Frederiks effect, and has a potential for applications in fast electro-optical devices such as phase modulators, optical shutters, displays, and beam steerers.more » « less
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Nematic liquid crystals exhibit nanosecond electro-optic response to an applied electric field which modifies the degree of orientational order without realigning the molecular orientation. However, this nanosecond electrically modified order parameter (NEMOP) effect requires high driving fields, on the order of 108V/m for a modest birefringence change of 0.01. In this work, we demonstrate that a nematic phase of the recently discovered ferroelectric nematic materials exhibits a robust and fast electro-optic response. Namely, a relatively weak field of 2 × 107V/m changes the birefringence by ≈ 0.04 with field-on and-off times around 1 μs. This microsecond electrically modified order parameter (MEMOP) effect shows a greatly improved figure of merit when compared to other electro-optical switching modes in liquid crystals, including the conventional Frederiks effect, and has a potential for applications in fast electro-optical devices such as phase modulators, optical shutters, displays, and beam steerers.
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Abstract The recently discovered ferroelectric nematic (
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Conference Paper:
- https://doi.org/10.1117/12.2676160
