The U.S. Patent and Trademark Office recently released a patent (Patent No. 9,460,332) for a ‘capacitive fingerprint sensor including an electrostatic lens,’ applied by Apple.
This patent puts forward a description of a Touch ID sensor which would use an electrostatic lens to read user’s fingerprints through other components of the smartphone such as display stacks and touch screens, as reported by AppleInsider.
To make this possible, the company had to reportedly face a number of issues. For instance, it was needed to embed a fingerprint sensor underneath the display. This, in turn, would have caused the blurring caused by the gap, which resulted in the loss of resolution and finicky touch input when the user made use of Touch ID sensor on iPhone’s screen.
Apple has discovered a solution, after it’s patent proposed the use of electrostatic lenses. The patent filing details how Apple could implement the new fingerprint sensor “as an integrated circuit connected to a bottom surface of a cover sheet, near the bottom surface of the cover sheet, or connected to a top surface of a display.” The patent also laid out an example wherein the position, relative voltage and shapes of the patterned conductive layer could be altered according to the shape of the user’s fingerprint. That means the color of the screen remains intact and multi touch display functions would still work properly.
In the patent, Apple also describes how the user will be able to scan multiple fingerprints, or even your palm at once by using the same technology. This is possible as the specific point on the screen would be able to capture by the sensor technology (such as an unlock button on the lock screen), it can also read fingerprints from any point on the touchscreen’s surface.
Of course, Apple and other tech companies are known to file technology patents that never end up in real products, but moving the TouchID sensor from the home button to the underneath a device’s display makes a lot of sense. A physical home button takes up a lot of space on the iPhone’s bottom bezel, so moving the sensor underneath the display and opting for an onscreen home button could allow Apple to design iPhones with a slimmer bezel altogether.