Polarization-independent electronically tunable liquid-crystal spectacles
Phys. Rev. Applied 24, 024071 – Published 29 August, 2025
DOI: https://doi.org/10.1103/3m2d-k24l
Abstract
Since Benjamin Franklin proposed the first bifocal lenses in 1784 and Bernard Maitenaz invented the first varifocal lenses in 1959, researchers worldwide have been actively working on developing electronically switchable lenses for spectacles with the goal of addressing vision issues faced by individuals with both presbyopia and myopia. Liquid-crystal (LC) refractive or diffractive Fresnel lenses have emerged as a promising solution. However, the degradation of incoherent imaging, caused by microstructures, diffraction, and chromatic aberration, makes LC refractive or diffractive Fresnel lenses not suitable for spectacle applications. LC gradient index (GRIN) lenses have been suggested and successfully demonstrated in laboratories as an alternative to LC Fresnel lenses. However, how to bridge the gaps between engineering and physics as well as from laboratory to industry is still a question. To address these gaps, we present here electrically switchable spectacles based on LC GRIN lenses, which have the potential for mass production. Additionally, we discuss the optical principles underlying polarization-independent LC GRIN lenses, based on a wave-plate model. We present a breakthrough that is a significant advancement in LC-based tunable spectacles and that may provide vision correction for individuals worldwide. The impacts of this study are not only ophthalmic applications but also machine vision for artificial intelligence as well as augmented reality.
