The 2017 iPhone 8 is rumored to introduce a new design and exciting new features to celebrate the 10th anniversary of the iPhone. And one of the most persistent rumors is that it will have an edge-to-edge OLED display that covers its entire front. To achieve that, Apple will have to embed the home button and Touch ID fingerprint sensor in the display itself.

iPhone 8 Concept
Image source: iVenyaWay / YouTube Video Screenshot

Electrostatic lenses to help embed Touch ID under the display

Until now, it was unclear how Apple would incorporate Touch ID fingerprint sensor into a device that lacks a home button. On Tuesday, the Cupertino company was granted patent for a “Capacitive fingerprint sensor including an electrostatic lens,” which could help it incorporate the Touch ID in iPhone 8 display. The patent describes a technology that could detect and read your fingerprints through other components of a device such as touchscreens and display stacks.

iphone-8-patent
Image Credit: Apple Inc. / USPTO

According to the patent filing, the capacitive sensing technology works through gaps in space, effectively allowing the Touch ID sensor to sit underneath the display. In common fingerprint sensors available today, the separation between where you place your finger and the capacitive sensing array leads to “blurring of the electric field.” It causes loss of resolution of the fingerprint images and decreased recognition accuracy.

Apple’s patent describes the use of electrostatic lenses spread across an array of capacitive sensing elements to pick up an accurate reading of a user’s fingerprint. It would help improve the fingerprint image resolution despite the distance between the Touch ID module and the place on the display where a user places their finger. The location and setting of these electrostatic lenses depend on the geometry of the device and the “effects of any intervening components.” However, Apple has mentioned touchscreens and display stacks many times in its patent.

Will Apple use this tech in iPhone 8?

The patent was originally filed in September 2014. It credits Jean-Marie Bussat as the inventor of the electrostatic lens technology. Though Apple now has the technology to embed the fingerprint sensor in the display, it is unclear whether the company will use it in the iPhone 8. Apple may also need to make some other enhancements before introducing an edge-to-edge OLED screen.

There are other technologies as well that could help incorporate a fingerprint sensor behind the display. For instance, Qualcomm’s Sense ID uses ultrasonic waves to read a user’s fingerprint through glass, metal, and plastic surfaces.

The iPhone 8 is rumored to feature an improved dual-camera, a faster processor, wireless charging, rapid charging technology, an all-glass design, and an iris scanner. According to a recent report, some of the iPhone 8 hardware is being developed at Apple’s R&D center in Herzliya, Israel. Apple is expected to unveil the device in September 2017.