Face ID

Face ID is a facial recognition system, designed and released by Apple Inc. and will be included in the iPhone X. It was introduced on September 12, 2017 at the Steve Jobs Theater by Phil Schiller and Craig Federighi.

It is meant to replace Touch ID rather than to add another security mechanism. It allows users to unlock Apple devices, make purchases in the various Apple digital media stores (the iTunes Store, the App Store, and the iBooks Store), and authenticate Apple Pay online or in apps.

Face ID works by projecting more than 30,000 infrared dots onto a face and producing a 3D mesh. Apple claimed the probability of someone else unlocking a phone is 1 in 1,000,000 as opposed to Touch ID at 1 in 50,000.

Apple has stated that facial recognition information is stored locally in a secure enclave on the Apple A11 Bionic chip and is not stored in the cloud.

Invisible infrared light helps identify the face even when it's dark.

More than 30,000 invisible infrared dots are projected onto the face to build a unique facial map.

An infrared camera reads the dot pattern, captures an infrared image, then sends the data to the Secure Enclave in the device's A11 Bionic chip to confirm a match.

Face ID may be prone to abuse by an identical twin.

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Wikipedia