Ask Apple fans what they would most like to see in an upcoming iPhone and the answer is often the return of Touch ID, ideally placed in the display itself. But despite many rumours, it’s not there yet – and the latest report suggests it could be nearly three years.
But we do know for sure that Apple is still working on it due to newly uncovered patents. As discovered by Patently Apple, Apple is working on something called “Under-Display Fingerprint Sensing based on Off-Axis Angular Light”.
Here is the patent abstract: “A touch-sensing device includes a light-emitting layer covered by a transparent layer and configured to illuminate a surface that touches the transparent layer and transmit reflected light rays from the surface to it underlying layers allows. The underlying layers include an optical coupling layer, a collimator layer, and a pixelated image sensor. The optical coupling layer bends the reflected light rays to produce oblique light rays. The collimator layer includes a number of apertures to collimate the received light rays. The pixelated image sensor captures the collimated oblique light beams.”
There have been previous patents focused on this, but the fact that new ones are emerging tells us that this remains a key focus for the company. And what’s interesting here is the patent’s interest in off-axis light.
You are familiar with the off-axis. It makes OLED displays look a bit strange from an extreme angle, for example, and it’s the hallmark of a good OLED display that you don’t notice when you turn the screen away from you. The patent explains why this is important:
“For certain objects, oblique light forms stronger imaging signals than light that is perpendicular to the imaging plane. For example, a fingerprint sensor system/device with multi-directional illumination, such as an under-display fingerprint sensor device, may use angled angle filters to capture the stronger signals and improve image contrast.”
Well, that’s all very exciting, even if the other reports suggest we’ll have to wait to see this kind of Touch ID on the iPhone. And the patent even mentioned that the technology is not just limited to phone screens and could be used in a wearable device like presumably an Apple Watch.
And on the same day, Apple also published another patent with related news. And it’s pretty cool too.
It says “Recognizing a gesture of a person wearing a handheld electronic device” and reading through it suddenly says: “The display may also provide an input surface for one or more input devices, such as a touch-sensitive device and/or a fingerprint sensor.” Allowing the watch (or other wearable device) to determine which limb is wearing the device isn’t the main focus of the patent, but it does show that Apple is really focusing a lot of firepower on the prospect of under-display sensors.
In other words, we might have to wait a while for under-screen sensors to make their way to Apple products, but it seems likely they’re on the way. Who knows, maybe the Apple Watch will have Touch ID under the screen first.