From Novel Soft Materials to Switchable Contact Lenses

by C. Jones (Leeds University, UK, j.c.jones@leeds.ac.uk)

The use of liquid crystals is well established in displays used in smart phones and large area TVs. During the Annual SoftComp Meeting 2016 in Ancona, a new academic team, having recently joined the Soft Matter Physics group at the University of Leeds, UK, was introduced to the community. Professors Cliff Jones, Helen Gleeson, and Dr. Mamatha Nagaraj say they made the move to Leeds because the group there is amongst the best in Europe. In Ancona Jones presented a selection of recent work on new liquid crystals and applications beyond conventional displays.

He described a new effect found in bent core liquid crystal compounds that form an optically isotropic dark conglomerate phase [1]. An electric field induces an optic axis parallel to the field direction so that the material appears to be isotropic in both ON and OFF states, but the refractive index is continuously lowered. Electrically tuneable refractive indices have enormous potential for switchable lenses and adaptive optics.

One such lens could be a switchable contact lens [2]. Jones and Gleeson are already working on adding liquid crystals to contact lenses to solve the problem of age-related eye deterioration, presbyopia. As they approach 50 years of age, contact lens users currently need to adapt to seeing two focused images for near and far distances simultaneously. The Leeds research allows the lenses to switch between focal lengths and provide the extra 2.5-dioptre power needed by the ageing eye to bring near objects sharply into view. Having successfully demonstrated the lens, the team are investigating printing invisible drive electronics onto it, and methods for automatically triggering operation by detecting gaze direction or other eye changes.

Jones has only recently joined academia, having previously founded the company Displaydata. As CTO, he helped invent and commercialize a shelf-edge labelling system that combined zero-power bistable LCD with novel RF communications. “Having solved many of the power issues for replacing paper labels in the retail sector, we are now in a good position to shrink the electronics yet further and provide exciting advances for the healthcare sector too”, says Jones.

References:

[1] Nagaraj M et al. Phys. Rev. E. 2015;91(4):042504.
[2] Syed IM et al. Opt. Express. 2015;23(8):9911-9916.

Note: This article was first published in July 2017 in  the SoftComp Newsletter Issue 14.