How Apple could use a fingerprint scan to unlock your iPhone

Apple(s AAPL) has stayed quiet — as usual — on what it’s been up to with AuthenTec since it acquired the mobile security company a year ago. But a patent filing offers some insight into what the two are partnering on: fingerprint sensors that can be embedded into displays.

The U.S. Patent and Trademark Office on Thursday published a patent application attributed to Apple based on work done by AuthenTec’s co-founder, as noted by AppleInsider this morning. The patent is is for a chip that can be embedded in a mobile device that will sense fingerprints on a display as a way of authenticating a user before giving them access to a device.

Apple’s patent sounds like it will allow the chip to be inserted in the device, but gives Apple’s device engineers more room to work with than traditional biometric security solutions. From the application:

When using a semiconductor fingerprint sensor, or integrated circuit fingerprint sensor, in a portable electronic device, for example, a mobile telephone, it may be desirable to locate the integrated circuit of the fingerprint sensor separately from the finger sensing region. Separating the finger sensing integrated circuit (IC) from the finger sensing area may be particularly advantageous when the finger sensing area is relatively thin and transparent so that it may be placed over the top of a display of the portable electronic device, and wherein the IC may be located in a nearby non-display region of the portable electronic device.

There’s been a lot of speculation that the next iPhone will have a fingerprint-sensing security feature. Much of that has been assuming the sensor would be under the home button. But being able to put it in a display could mean iOS’s traditional “swipe to unlock” could seamlessly include another layer of security — for an iPhone, an iPad, the touchpad of a MacBook — or possibly even a future wearable device.

Of course, there’s the standard caveat for any Apple patent filing: the company files a lot of patents and it doesn’t necessarily mean the technology will make its way to Apple product some day. But in this case, it’s the first patent application to come out of Apple’s purchase of AuthenTec. We know the two companies were working on a project together even before the acquisition, and this is a good indication of the direction the two are going in.