A mysterious Apple patent has revealed that the company has been working on its own wearable computers since at least 2006.
Patently Apple uncovered the documents, which show that Apple applied for a broad patent covering wearable devices six years ago. The patents were granted in 2009.
The patent is very broad, and describes a "Portable Display Device" which "may be any device that is meant to be worn by a user and that is capable of presenting media content to the user".
Theoretically that might even cover the previous version of the iPod Nano, which was wearable with an attached clip and could display photos.
But the patent goes on to mention glasses similar in theory to those already demonstrated by Google.
"A set of goggles that fit over the user's eyes with display and perhaps sound producing capability, a faceplate that covers the front of the user's face with display and perhaps sound producing capability, or any other headwear that has display and perhaps sound producing capability."
The device could be wired or wireless, and would include proximity sensors and the ability to make phone calls.
The full details of the patent are worth following at Patently Apple, but don't expect these to turn up on the shelves any time soon. Apple is known to patent ideas well in advance of releasing a product, and regularly keeps devices in internal-only testing for years before commercialising the technology.
As CEO Tim Cook said in an interview with NBC recently:
"Our whole role in life is to give you something you didn't know you wanted. And then once you get it, you can't imagine your life without it."