Curved LCD could be used for displays in contact lenses
New research conducted at Ghent University, Belgium, has resulted in the development of a curved LCD display which can be integrated within a contact lens. While still in its infancy, the project lays the foundation for future fully-pixelated contact lens displays which could be used for both medical and cosmetic purposes, in addition to a heads-up-display (HUD) further into the future.
In contrast with existing LED-based contact lens displays that can only show a few pixels, the LCD contact lens allows the entire display surface to be used, and thus more pixels are available than before, enabling a greater flexibility of pixel sizes. However, manufacturing such a small, flexible display also posed significant challenges.
“Normally, flexible displays using liquid crystal cells are not designed to be formed into a new shape, especially not a spherical one,” explained Jelle De Smet, the main researcher on the project. “Thus, the main challenge was to create a very thin, spherically curved substrate with active layers that could withstand the extreme molding processes. Moreover, since we had to use very thin polymer films, their influence on the smoothness of the display had to be studied in detail. By using new kinds of conductive polymers and integrating them into a smooth spherical cell, we were able to fabricate a new LCD-based contact lens display.”
The researchers posit that the display could be used as a method of controlling the light which reaches a damaged iris, in addition to cosmetic purposes, such as a contact lens which allows the wearer to change eye color on a whim, or an adaptive replacement to sunglasses. “Spherical curve” refers to the specific curve form that this lens, like many other contact lenses, describes.
Perhaps most interestingly, subsequent iterations of the technology could eventually be tasked to superimpose an image onto the user’s normal view, in a way which sounds somewhat similar to Google’s Project Glass, but without the cumbersome headgear.
At present, the prototype lens can only display relatively simple patterns – the demonstration involved a dollar sign being displayed in the lens. But in the next few years, the researchers imagine fully autonomous contact lenses which feature the technology to be brought to market.
The new display was produced at the Centre of Microsystems Technology (CMST), the associated laboratory of Interuniversity Microelectronics Centre (IMEC), at Ghent University.
The video below shows off the new contact lens display with the aforementioned dollar sign example graphic.