New graphene-powered soft lens could pave the way for smarter glasses, cameras and medical devices

The ability to change focus instantly is something most people take for granted. Every day, our eyes effortlessly switch between reading a book, recognising a face across the room or watching a bird fly overhead. Replicating that remarkable technological flexibility, however, has proved far more difficult. 

Researchers at Queen Mary University of London, led by Prof. James Busfield, have taken an important step towards making adaptive lenses smaller, lighter and more practical by developing a new transparent graphene-based material that allows soft lenses to change focus electronically without bulky moving parts.  The work has eliminated the key design constraints limiting electrostatically actuated lenses, opening the door of opportunity for compact medical imaging devices, autofocus cameras and wearable displays. 

Published in Advanced Functional Materials, the study demonstrates how ultra-thin transparent electrodes made from reduced graphene oxide can be integrated into a soft, electrically driven lens. The result is a compact device capable of changing its focal distance simply by applying a small electrical field. 

Unlike the rigid lenses found in conventional cameras, microscopes and optical instruments, the prototype behaves more like a living eye. When electricity is applied, a soft membrane gently stretches the lens, subtly altering its shape and bringing objects at different distances into focus. 

This is in direct contrast with the functionality of conventional electrostatically actuated adaptive lenses, which position their electrodes around the edge of the lens because the materials block light. Moreover, traditional electrically driven soft lenses require flexible electrodes to move the lens, but these electrodes are often opaque, making them unsuitable for optical applications. 

By engineering transparent electrodes from reduced graphene oxide, the research team was able to integrate them directly onto the expanding actuator beneath the lens itself. This new architecture dramatically reduces the device’s size and complexity, while allowing it to change focus electronically.   

By carefully controlling the amount of graphene deposited onto the soft membrane, the researchers identified the balance between electrical performance and optical clarity needed to create a functioning adaptive lens. Their prototype successfully adjusted its focus across a range of distances while maintaining a compact design. 

Although still at the research stage, the technology could open the door to a new generation of adaptive optical devices that are thinner, quieter and more energy efficient than existing systems. 

“This is exciting. It means that in the future, similar technology could find applications in autofocus cameras, wearable displays, virtual and augmented reality headsets, miniature medical imaging devices and scientific instruments where conventional mechanical focusing systems add weight, complexity or cost.” says Giacomo Sasso, first author of the study.  

The research also highlights the growing potential of soft robotics and advanced materials to transform everyday technologies. 

”Instead of relying on motors and gears, electrically active polymers behave more like artificial muscles, changing shape smoothly and silently in response to electrical signals. Coupled with graphene's exceptional electrical properties, they offer engineers an entirely new approach to designing optical systems.” adds second author of the study, Alec Lamoreux.   

While further work is needed to improve the transparency of the graphene electrodes and optimise their performance, the findings demonstrate that soft, electrically turnable lenses can be built using simple manufacturing techniques and inexpensive materials. 

The study underscores Queen Mary University of London's expertise in advanced materials, soft robotics and biomedical engineering, and demonstrates how fundamental research into graphene and smart materials can translate into innovations with the potential to improve future healthcare, consumer technology and scientific imaging. 

You can read the full study in Advanced Functional Materials via the following link.