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What is Face ID? Apple’s face unlock system explained

When you’re opening your iPhone, you may be offered the choice of using Face ID – but what is this and how does it work?

If you use an iPhone, then you’ve most probably come across the term Face ID before, during set-up or else when you unlock your phone.. However, if you’re not sure what this is, or are simply curious to learn how it actually works, then just read on for a full explanation.

What is Face ID?

Face ID is Apple’s facial recognition feature, present on iPhones and iPads. When activated, the device will use its front-facing cameras to scan your face in order to verify that it is you using the phone rather than someone else. It’s most commonly used for unlocking your phone, but it can also be used for in-app verification if you’re making a purchase for example.

How does Face ID work?

Apple claims that the facial recognition technology is among its most advanced hardware and software, and it’s not hard to see why. Here is the manufacturer’s explanation for how the technology works:

The TrueDepth camera captures accurate face data by projecting and analysing thousands of invisible dots to create a depth map of your face. It also captures an infrared image of your face. A portion of the neural engine of the A11, A12 Bionic, A12X Bionic, A13 Bionic, A14 Bionic and A15 Bionic chip – protected within the Secure Enclave – transforms the depth map and infrared image into a mathematical representation and compares that representation with the enrolled facial data.

Not only is this system very accurate, but it can also work despite challenging conditions, such as when you’re wearing a scarf, glasses, make-up, or growing out facial hair.

How do you set up Face ID?

If your iPhone has Face ID, then you’ll be prompted to set it up when you start your phone up for the first time. However, if it was not implemented at that stage then you can put it in place at a later date by going into your phone’s Settings app, and tapping on Face ID & Passcode where you’ll see the option to set up Face ID.

How do you use Face ID?

It’s not at all difficult to use Face ID; in fact, all you need to do is just look at your iPhone’s selfie camera. When seeking to unlock your phone, the TrueDepth camera will be woken up by either touching the screen or raising it up, and then it just needs to scan your face or eyes to unlock.

Apple claims that the tech works best when the phone is 25-50cm away from your face, and it can be used whether held in front of your face or lying flat on a surface.

Is Face ID secure?

According to Apple, Face ID is highly secure; it states that “the probability that a random person in the population could look at your iPhone or iPad Pro and unlock it using Face ID is less than 1 in 1,000,000 with a single enrolled appearance, whether or not you’re wearing a mask.” After 5 negative login attempts you will be required to enter your PIN instead.

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