First 3D-Printed Contact Lenses with Built-In LED

LED: the latest in contact lens technology.

In the last few years, there’s been a lot of discussion in the tech world about wearable technology. Many experts have predicted that wearable technology is the next logical step in technological advancement. Already, technology giants such as Google and Apple have started to develop wearable technology for consumers.

Apple, for example, has recently released Apple Watch which is a sophisticated smart watch that connects to a person’s iPhone allowing them to send texts and use apps conveniently without having to take their phone out of their pocket or purse. Google, on the other hand, had released a prototype of an optical head-mounted display, typically referred to as smart glasses, called Google Glass. These smart glasses were designed to display information on the lens in a way that is similar to a smartphone display. While the Google Glass prototype was only available to the public for a short time, which ended in January 2015, Google has stated that it remains committed to developing optical head-mounted display technology.

Beyond Smart Glasses

While many in the tech world are still waiting for the successful release of smart glasses into the mainstream, some are already beginning to think about the future beyond smart glasses. In creating a contact lens with a built-in LED display, researchers at the University of Washington have already taken steps towards the future. Currently, it can only display a single pixel of information. However, the researchers believe that this technology can eventually be developed to display enough information to be comparable to optical head-mounted displays like Google Glass.

In theory, it’s not difficult to design a contact lens with the ability to display information. The difficult part is actually fabricating the extremely small parts and putting them together on a miniature polymer disk. In fact, it was impossible for the researchers to construct a contact lens with built-in LED until the 3D quantum dot LED printer was developed.

3D Printed Lens Material

Princeton University’s McAlpine Research Group, led by Michael McAlpine, developed a 3D printer which is capable of making 3D quantum dot LEDs or QLEDs. They’re extremely thin, flexible, and transparent which makes them the ideal material for smart contact lenses.

The researchers at the University of Washington used this printer to make the first contact lens with built-in LED display by printing the different layers of interacting material. First, the emissive layer contains the quantum dots. They’re placed between a layer that donates electrons and a layer that accepts electrons. The movement of the electrons causes the quantum dots to radiate photons of light at specific wavelengths, enabling the wearer to see a display of colors and images. Because this requires power, a wireless antenna is embedded in the lens. There is also an integrated circuit which is only one thousandth of a human hair thick placed inside the lens to store the energy. The energy is ultimately transferred to a chip containing a single LED.

The researchers, who published their findings in the Journal of Micromechanics and Microengineering, believe this technology will be used to improve the display of other small devices. Certainly, these findings demonstrate that the future of wearable technology is well on its way.