The U.S. Patent and Trademark Office has published an Apple patent application that would essentially turn the Apple Watch’s digital crown into a Touch ID sensor. The crown would stick out from the main body of the watch, and use light-transmission technology to guide an image of the user’s finger to a sensor located within the body of a watch.

The system would give Apple another way to bring Touch ID to the Apple Watch. A separate patent application details a flexible antenna that could be integrated into the band of the watch to free up more space in the body for things like fingerprint sensors.

Apple has also explored other forms of biometric authentication. The company has received a patent for a watch-based Face ID system, and conceptualized a sub-epidermal imaging camera that could verify the identity of the wearer based on factors like skin color and vein patterns.

According to the latest patent, the crown could be shaped like a lens to facilitate the transmission of light to the sensor and reduce the risk of a false match. Any objects that are not in direct contact with the crown would be out of focus, so the system would filter out and ignore any other activity that gets picked up. However, a system with a slightly different configuration could just as easily be used to enable basic gesture recognition capabilities.

As with most patents, there’s no guarantee that the technology will ever be deployed in an Apple Watch, especially since Apple is currently trying to patent a design that would remove the digital crown entirely. The patent for a crown-based form of Touch ID was initially filed in the fourth quarter of 2018, and demonstrates yet again that Apple is still searching for new ways to take advantage of its Touch ID technology.  

Source: Patently Apple