Google has a thing about contact lenses. The company has done a lot of work with contact lenses used in health applications. It’s now patented a technology that employs the contact lens as an identification device.

The new patent describes a contact lens that covers all or part of the iris of the eye, and one or more light sensors embedded in the surface of the contact lens collects reflected light off the iris.

The sensors assemble an image of the iris, which is then compared with an image of the same iris contained in computer memory. If the two images match, a door might be unlocked for the wearer, or a file containing privileged information might become accessible, for example.

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The patent doesn’t go into specifics about applications for the technology. The lenses presumably could be used for biometric authentication purposes within a number of technologies and in various contexts.

Google has also been busy testing smart contact lenses that might one day be used by diabetics to measure their blood sugar levels. In that type of lens, a tiny chip and sensors are embedded between two layers of lens material. Tears reach the sensors through a tiny perforation in the lens material, and the sensors derive blood sugar levels from the liquid. The lens can test blood sugar once every second.

Last July, Google announced a partnership with the pharma company Novartis to further develop the latter lenses.

Research by Mikhail Avady at SmartUp Legal