Chalk one up for University of Michigan researchers, who announced earlier today that they have come up with a room temperature light detector that could fit inside contact lenses. This could be every science fiction fan’s fantasy brought to life, as the possibility of contacts going infrared could become reality.
Researcher Zhaohui Zhong said in a statement that the infrared vision equipment, which would not require the traditionally bulky cooling equipment that has traditionally been mounted on specialized glasses, is so thin that it could be stacked on a cell phone or integrated into contact lenses. Zhong is an assistant professor of electrical engineering and computer science at the University of Michigan, and was involved with other researchers in the intensive design project.
The material used in the project is a single atom thick and is known as graphene. It’s been recognized in the past for its ability to function as an infrared detector, but the big problem is that while it is incredibly lightweight, it also absorbs only 2.3 percent of the light that hits it, which means that there has to be further work with the material before researchers deem the use of graphene as an infrared detector in contact lenses an unqualified success.
Zhong’s findings were published in the journal Nature Nanotechnology, and the report, which was co-authored by Theodore Norris, Chang-Hua Liu, Zhong and You-Chia Chang, also said that graphene was also a promising candidate in detecting objects using infrared means as well as picking up light among the ultraviolet spectrum. The device that Zhong and his graduate students from the University of Michigan is as small as the nail on one’s pinky finger, and Zhong says it is quite feasible for the team to be able to design something that can be easily stacked onto a contact lens or integrated into a cell phone. He notes that giving contact lenses the capability of going infrared allows wearers to interact with their environment in a whole new way.
Graphene does not just pick up light along the infrared spectrum; it also detects visible light and ultraviolet light as well. As a way of boosting graphene’s light detecting capabilities, scientists took two layers of graphene and sandwiched an insulator between the two sheets. The bottom layer had a current of electricity going through it and the top layer allowed electrons to go free whenever it detected light. This, in turn, would affect the lower layer of graphene, as the freed electrons would then affect the flow of electricity on the bottom layer. The researchers would then check what the change in current was to see how much light was detected.
What is most interesting about this device is that it is capable of doing what others before it have not been able to do. The device from the University of Michigan scientists is able to function rather well at room temperature, while other infrared detectors have to be operated with mounted cooling devices, which may not make surveillance activities that easy, given the bulk of infrared goggles. Zhong notes that there are possibilities for mounting the work on a pair of contacts, so that could mean regular consumers could be seeing their loved ones through infrared vision. However, it should also be realized that while law enforcement officials might have need of infrared version, civilians may be hard pressed to think of legitimate uses of contact lenses with students who have no real need of infrared vision.
While there is a possibility that humans do not, has a whole, have a plan or will have a plan in place to explain precisely why they need to have contacts go infrared in the first place, the advance in science is completely impressive. Meanwhile Zhong and his crew of fellow scientists are continuing to explore the unique applications of graphene so that one day, perhaps contacts really could go infrared.
By Christina St-Jean