The US Patent and Trademark Office has published a Google patent application
that appears to describe many of the technologies used in the company's Glass wearable display system
. The authors describe the limitations to current wearable displays, including traditional screens that block the wearer's vision or heads-up displays that typically serve as passive headwear reliant on signals from external sources.
"Accordingly, further advances in wearable devices including displays have been needed," the filing reads.
Some of the descriptions focus on comfort, balancing the weight between the nose pads and the temples, and providing a way for the transparent display to be moved to different positions. Other details provide insight into the on-board computing system and a touchpad for input.
The filing, which was spotted
, also lists several other embodiments that take a different approach than the Google Glass hardware that so far has been shown to the public. Although the current Glass system utilizes a prism to present information without completely obscuring a user's vision, the filing also describes using a "laser or LED source" and a scanning system to "draw a raster display directly onto the retina."
Google recently extended its prototype program to include non-developers, through a competition that requires applicants to describe how they would use Google Glass, though the company has yet to announce firm details on a public launch for final production hardware.