Google has officially announced its intentions to develop smart contact lenses, as a noninvasive method of measuring blood glucose levels in people with diabetes, according to Google's blog.

"At Google[x], we wondered if miniaturized electronics—think: chips and sensors so small they look like bits of glitter, and an antenna thinner than a human hair—might be a way to crack the mystery of tear glucose and measure it with greater accuracy," project cofounders Brian Otis and Babak Parviz said in the post.

The contact lens is comprised of a miniturized glucose sensor and wireless chip embedded between two layers of contact lens material, although the cofounders add that eventually it might have tiny LED lights that would act as an early warning when glucose levels have dropped or risen past certain thresholds.

The technology is far enough along in the process to validate multiple clinical research studies in order to refine the initial prototype, but the cofounders said they are still far from commercial distribution and are in talks with the FDA -- which made headlines a few weeks back. Like they did with Google Glass, the Google[x] team is also on the lookout for potential partners that could develop apps, which would integrate the data from lens into a system for the user or a doctor to see.

MobiHealthNews first wrote about Parviz in 2009, when he announced his work with contact lenses. While he was at the University of Washington, Parviz tested a prototype of smart lenses on rabbits, which just contained one LED light. At the time, Parviz was already envisioning a future where the lens could pick up vital signs through biosensors.

“The true promise of this research is not just the actual system we end up making, whether it’s a display, a biosensor, or both,” Parviz said at the time. “We already see a future in which the humble contact lens becomes a real platform, like the iPhone is today, with lots of developers contributing their ideas and inventions. As far as we’re concerned, the possibilities extend as far as the eye can see, and beyond.”

In 2011, Microsoft Research announced they were working on the technology with Parviz, but the researcher is now working with Google X instead.

Up until now, continuous glucose monitoring has been an invasive process, requiring the user to wear a patch with an attached sensor needle. CGMs also usually require users to stick themselves with needles and do more traditional tests with a meter to calibrate them every so often.

While Google Glass has some health implications and the company recently announced Calico which aims to tackle issues such as illness, age, or even death, this is one of the company's first big projects in digital health hardware. Over the years, MobiHealthNews has tracked Google's health efforts, which have included updates to the search engine so that it was friendlier to health-related inquiries, its PHR venture Google Health, which ultimately failed, and Google Helpouts, a program on Google Hangouts in which users can pay professionals in various fields of study, including health, to answer their questions.

Even before Parviz announced his experiments, different researchers were working to develop smarter contact lenses. In 2008, a team from the University of California Davis, assistant professor of biomedical engineering Tingrui Pan and postdoctoral researcher Hailin Cong developed a contact lens made up of a material called polydimethylsiloxane (PDMS), which was strategically layered with powdered silver to create conductive wires.

In the shape of a contact lens, this device could be used to measure pressure in the eye, which researchers said could lead to glaucoma and potentially blindness.

Another company in Switzerland has brought smart contact lenses that measure the risk of glaucoma, which they've called Triggerfish, to a commercial audience in Europe. While the company has a CE mark, its website says it is still waiting for approval in the United States.

Passively sensing glucose levels via contact lenses and the wearer's teardrops is just one of many ways that medical device companies and researchers have investigated over the years. Other contenders have looked for ways to measure glucose via sweat, saliva, and interstitial fluid.