Apple patent reveals a less power-intensive way to track user’s eyes

We have seen several patents popping up regarding the Apple Glass wearable device in the past few months. The latest in the list is the patent titled “Method and Device for Eye Tracking Using Event Camera Data." Spotted by Apple Insider first, the patent talks about an eye-tracking system that also includes a camera. The camera might be focussed on the user’s gaze, which is then transmitted to the processor. 

"[In typical systems," a head-mounted device includes an eye tracking system that determines a gaze direction of a user of the head-mounted device," says Apple in the patent. "The eye tracking system often includes a camera that transmits images of the eyes of the user to a processor that performs eye tracking."

But Apple thinks that transmission of images at a certain frame rate for enabling eye tracking might require a communication link with a ‘substantial’ bandwidth. And this process might increase heat and may indeed result in more power consumption.

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So, Apple’s solution is to this is cut down on the processing needed to track the wearer’s eyes. "[One] method includes emitting light with modulating intensity from a plurality of light sources towards an eye of a user," says the patent. "The method includes receiving light intensity data indicative of an intensity of the emitted light reflected by the eye of the user in the form of a plurality of glints," it continues. "The method includes determining an eye tracking characteristic of the user based on the light intensity data."

Essentially, the light is projected on the eye and the reflection is then tracked. And since the system would know how much light has been used to project into the eyes, its reflection might be used to track the user’s eyes.

This is however, a patent and things can still change at a later date. Apple has been actively experimenting at how it would track user’s eyes in the rumoured Apple Glass. We have even seen patents stating the use of an infrared emitter and more.