With user’s face closing to the screen, the proximity sensor starts the recognition process. The flood illuminater helps the TrueDepth camera system determine how much illumination will be needed for face recognition.
The dot projector projects over 30,000 dots in a known pattern onto the user’s face. Those dots are then photographed by infrared camera for analysis.
A 3D map of user’s face are then completed. The 3D model is then compared against the stored template. The phone authenticates the identity and unlocks or authorizes a payment.