Abstract
Purpose:
To investigate low-cost, large-aperture, and high-performance adaptive lenses for correction of presbyopia for the large population is of great significance. Here we propose a new design to achieve this goal.
Methods:
The new design is based on tunable refractive index of the liquid crystals and the hybrid lens structure. The conventional liquid crystal lenses based on the refractive lens structure is thick and hence the response time is slow. The previous liquid crystal lenses based on grooved structures suffer from poor alignment of the liquid crystal molecules even if an alignment layer is coated on the grooved structure. To overcome these problems, we adopt structures such as diffractive lens, harmonic diffractive lens, and Fresnel lens to reduce the thickness of the liquid crystal lenses, and in order to obtain reliable alignment of liquid crystal, an innovative technique is proposed. In this technique, nanoparticles are doped into liquid crystals for uniform homeotropic alignment. Only one alignment layer is needed on the flat surface of the substrate and no alignment layer is needed on the micro-structured surface. New liquid crystal materials can be used in this lens structure to make polarization-independent lens, and this is a great advantage since the thickness of the whole lens assembly can be reduced by half.
Results:
Adaptive liquid crystal lenses with large aperture (over 20 mm), large tunable range (over 3 diopters) and low driving voltage have been designed and fabricated. The lenses show high optical performance and are suitable for applications in adaptive spectacles and visual simulator.
Conclusions:
The low-cost electro-active tunable lenses with large aperture and good tunable range provide a viable solution to vision correction and vision assessment.
Keywords: 653 presbyopia •
404 accommodation •
414 aging: visual performance