A computer tracking where its user is looking isn’t that complicated, but eye tracking two people simultaneously is more challenging. Apple worked out a method, and sees the potential for games, security and even surgery.
The US Patent and Trademark Office granted Apple a patent on a “Method for operating an eye tracking device for multi-user eye tracking and eye tracking device” (Pat. No. 10,416,764).
This includes a discussion on the difficulties of tracking the eye movements of more than one person without devoting a camera to each one.
The patent then proposes a single-camera method in which each frame recorded is examined for new users and for the position of the eyes of already-located viewers. Also part of this process is determining if each new user is someone the computer recognizes.
The entire system is quite complex and clearly depends on the faster processors now available to do tremendous amounts of pattern recognition very quickly.
Applications for multi-user eye tracking
Apple’s patent filing proposes several uses for a computer being able to determine where several people are looking.
“With regard to games, in the past many games used to be played with multiple people sitting at the keyboard triggering actions in the game using different keys. Instead of two people using the same keyboard, it will be possible to control their characters using gaze instead,” note the patent’s authors.
A more professional use would allow a doctor and their assistant to share a screen. As the computer would know which of the two is looking at the screen at any given moment, it could show just the information that person needed.
In the security arena, a computer could detect if an unauthorized person behind an approved one is looking at a display and automatically shut itself off.
Whether the system covered by this patent will make its way into real-world products is unknown at this time. Companies like Apple regularly patent ideas that never leave the lab.