Mac Face ID
The patent abstract notes:
One embodiment may take the form of a method of operating a computing device in a reduced power state and collecting a first set of data from at least one sensor. Based on the first set of data, the computing device determines a probability that an object is within a threshold distance of the computing device and, if so, the device activates at least one secondary sensor to collect a second set of data.
Based on the second set of data, the device determines if the object is a person. If it is a person, a position of the person relative to the computing device is determined and the computing device changes its state based on the position of the person. If the object is not a person, the computing device remains in a reduced power state.
Mac Face ID would prevent the computer from going into sleep mode if someone is looking at the screen. It would also be able to wake the device from sleep mode without the user interacting with the device.