The patent, awarded to Apple on Tuesday and reported on by Apple-tracking site Patently Apple, describes several methods for improving standard biometric sensors to increase their accuracy and use them in new ways. The patent also mentions one important addition: The ability to embed the fingerprint sensor directly into the screen and use ultrasound imaging to help the fingerprint sensor finds a match.

“The most accurate but least common finger-scanning technology is ultrasound imaging,” Apple writes in the patent. “In this type of sensor, two transducers are placed on the x- and y-axes of a plate of glass—one each for receiving and transmitting—for propagating ultrasound waves through a glass plate; when the finger is placed on top of the glass, the finger impedes the waves and the receiving transducer can measure the alteration in wave patterns.”

Apple adds that the scanner type “is very new and largely untested in a variety of conditions, but initial results show promise for the technology.”

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In a layperson’s terms, Apple (AAPL) is essentially describing a new way to deliver its Touch ID fingerprint sensor. Rather than using a button that sits below its touchscreen, like it does now, the patent would allow the company to embed an ultrasound-based sensor directly into a device’s touchscreen.

Rumors have been swirling for years that Apple is at least considering changing its biometric technology. The most consistent rumor has been that Apple will eventually embed its Touch ID fingerprint sensor into its iPhone and iPad displays. Even Apple has hinted at the idea in numerous patent filings on the subject.

Touch ID’s history goes back at least to 2012, when the company paid $356 million for AuthenTec, one of the leading biometric sensor companies that provided the technology that would eventually become Touch ID. Since then, Apple has bundled its fingerprint sensor in its mobile products.

Meanwhile, Apple’s competitors have added fingerprint sensors in their own devices, though those largely sit on the back of devices.

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Apple mentioned one more thing in its patent that should be mentioned: Its technology could also be used to verify the validity of driver’s licenses. It suggests that Apple’s software could one day house a driver’s license and that its fingerprint sensor could be used to ensure it’s the user’s and is valid.

But like many companies, Apple patents a wide array of technologies that never come out. So while it’s possible that Apple’s in-glass, ultrasound-based Touch ID could eventually come to an iPhone, it also may not. And as Apple’s own patent suggests, the technology still needs to undergo far more testing before it can be green-lit.

Apple did not respond to a request for comment.