Liquid crystal lenses with tunable focal length

ABSTRACT

Lenses with tunable focal length play important roles in nature by helping species avoid predators and capture prey. Many practical devices mimic lens concept for imaging, sensing, and detection. This review covers fundamental optics of lenses and its extension to lenses made of liquid crystals (LCs). Three main types of LC lenses are described, namely, lenses with curved surfaces, flat gradient-index lenses and composite lenses. The review discusses advantages of LC lenses over their isotropic counterparts, challenges in their fabrication and control, as well as a variety of potential applications. We also discuss the current challenges associated with nematic LC lenses and their solutions. LC lenses are already having significant impacts on optics and optometry, and these impacts will grow with discovering new LC materials and new lens designs.

KEYWORDS:

• Liquid crystal lens
• lens design
• tunable focal length

Acknowledgements

The authors wish to express their appreciation to Dr Hung-Shan Chen for discussion and technical assistance.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This research was supported by the Department of Natural Sciences and Sustainable Development in the Ministry of Science and Technology (MOST) in Taiwan under Contract No. MOST 104-2112-M-009-010-MY3.