The wearable technology business keeps growing--while the wearables themselves keep getting smaller.

Google is the latest company to develop a product in the category. The search giant announced it is testing "smart" contact lenses that monitor glucose levels in tears to help people with diabetes manage their disease.

On the company's blog, the project's leaders, Brian Otis and Babak Parviz, said the contacts, which are currently in the prototype phase, could be equipped with technology such as "chips and sensors so small they look like bits of glitter" and "an antenna thinner than a human hair."

"All people with diabetes must still prick their finger and test drops of blood throughout the day. It's disruptive, and it's painful," Otis and Parviz write. "And, as a result, many people with diabetes check their blood glucose less often than they should."

Google is trying to integrate minuscule LED lights that will blink when glucose levels are either above or below a certain threshold, replacing the need to prick your finger and test your blood.

The company is looking for partners to develop smartphone apps that could track patients' glucose levels and even notify a doctor when levels become life-threatening.