Apple is continuing to explore different possibilities for in-display fingerprint recognition. The latest rumors come courtesy of a patent application that was filed with the European Patent Office, which details an “under-display optical fingerprint sensor with narrow field-of-view (NFV) collimator and a thin-film transistor (TFT)-based organic imager.”
In plainer terms, the system combines a collimator with a pixelated image sensor and a touch-display layer like an OLED display. If placed underneath a transparent surface, the display can send light up through that surface to bounce off of something on the other side. The collimator will then filter that reflected light and relay it to the sensor for identification.
Of course, smartphones represent the most obvious application of the technology. In that case, the screen would serve as the transparent layer, and the system itself would be able to recognize the fingerprint of the user when they place their finger on that screen. Doing so would enable in-display biometric authentication on devices with the technology.
According to the patent, the image sensor could be based on thin-film transistor (TFT) tech, while the collimator would be a bundle of optical fiber films separated with an opaque material. The application was filed in July of 2019, and was published on April 2.
There is no guarantee that the technology in this particular patent will ever make it into a consumer device, but it is yet more evidence that Apple is planning to introduce in-display Touch ID at some point in the future. The tech giant has filed multiple patent applications for various in-display authentication systems, including an OLED system, an acoustic imaging system, and an optical sensor.
Apple recently confirmed Touch ID’s return with the new iPhone SE, but that device places the scanner in the home button rather than the screen. Analyst Ming-Chi Kuo has previously predicted that in-display Touch ID would come to the iPhone in 2021.
Source: Patently Apple