Imec, the Belgium-based nanoelectronics research center, has worked with Ghent University and contact lens producer SEED to develop a contact lens integrated with LED light. The lens is presented at imec technology forum Japan (ITF Japan 2018) on November 19th, 2018.

The contact lens with an integrated LED light is made of hydrogel-based material and is embedded with an ultra-thin silicon microchip, radio‐frequency (RF) antenna for wireless energy transfer, and stretchable thin‐film interconnections. imec and CMST, an imec research group at Ghent University, made the spherical‐shaped electronics and SEED was responsible for embedding them into the hydrogel-based soft lens. Together they demonstrated a semi-passive smart lens with blue LED light powered by an RF coupling. Besides power transfer, the RF link can be used to calibrate the integrated transducers and reading the sensors out into a handheld device for further post-processing.

 
(Left: Self-standing flexible RF antenna with thin microchip, LED light and stretchable interconnections.
Right: Semi-passive hydrogel-based smart contact lens powered up by an RF wireless coupling. Image: imec)

The advancement of electronic systems makes it possible to integrate transducers into lenses for diagnosing and treating ocular diseases. The challenge is to integrate a complete autonomous system and make it as flexible as a soft lens, without compromising its oxygen-permeable nature and the integrity of the electronics components.

According to imec, the hydrogel-based soft lenses provide a wider range for applications including lenses with sensors and drug-delivery systems eye treatments at the congenital, post-surgery or trauma level. Contact lenses are less invasive and could continuously monitor eyes without discomfort.

Andrés Vásquez Quintero, imec researcher and professor at UGent, said, “Flexible and stretchable electronics hold a lot of promise for medical applications. They can be integrated in intelligent clothing, and even – when combined with highly miniaturized electronics – in smaller devices such as contact lenses. Major challenges have to be overcome to make a truly autonomous smart lens which is comfortable to wear and stable for a few days or even weeks. The integration of a LED light in a semi-passive RF wireless platform is the first important step towards a device that will change the life of many.”

Following steps will focus on developing active lenses with extended power autonomy in order to drive and readout the integrated transducers and on the design of micro-transducers compatible with stretchable systems similar to the one presented here.