Switchable liquid crystal contact lenses: dynamic vision for the ageing eye

Harry E. Milton; Helen F. Gleeson; Philip B. Morgan; John W. Goodby; Stephen Cowling; John H. Clamp

doi:10.1117/12.2044676

19 February 2014 Switchable liquid crystal contact lenses: dynamic vision for the ageing eye

Harry E. Milton, Helen F. Gleeson, Philip B. Morgan, John W. Goodby, Stephen Cowling, John H. Clamp

Proceedings Volume 9004, Emerging Liquid Crystal Technologies IX; 90040H (2014) https://doi.org/10.1117/12.2044676
Event: SPIE OPTO, 2014, San Francisco, California, United States

Abstract

The inability of the eye to focus on nearby objects, presbyopia, is suffered by ~100% of people over the age of 50. Liquid crystal (LC) spectacle lenses have shown great potential for correcting presbyopia. However, correcting presbyopia in contact lens users has proven elusive and existing commercial options suffer significant compromises in vision and comfort. We describe a novel contact lens that includes a liquid crystal element that offers to correct presbyopia without the compromises associated with other technologies. We fabricated variable focus lenses using a balanced optical system, providing the additional optical power presbyopes require for near vision (typically +1.00 D to +2.00 D). The system uses positive optical power from the two substrates and variable negative optical power from the LC layer to form a balanced optical system which, when unpowered, corrects distance vision. Upon voltage application, the liquid crystal layer decreases in refractive index, resulting in additional optical power in the system, offering correction equivalent to reading glasses. Our new technology is based on a traditional contact lens material which could be placed directly on the eye. The liquid crystal lens employed is well suited to the small optical areas associated with contact lenses. We compare several different LC materials and geometries which are suitable for our application, and discuss the influence of material and geometry on switching times, optical quality and operating voltage. Our contact lenses typically switch ±2.00D in response to < 10 V_rms with response times of the order of a second.

Citation Download Citation

Harry E. Milton, Helen F. Gleeson, Philip B. Morgan, John W. Goodby, Stephen Cowling, and John H. Clamp "Switchable liquid crystal contact lenses: dynamic vision for the ageing eye", Proc. SPIE 9004, Emerging Liquid Crystal Technologies IX, 90040H (19 February 2014); https://doi.org/10.1117/12.2044676

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available