Apple was granted a patent for a head-mounted display apparatus on Tuesday.

Titled “Peripheral treatment for head-mounted displays,” it describes how images could be projected to generate a peripheral display that would create “an enhanced viewing experience” for the user.

Apple calls its implementation a head-mounted display (HMD) rather than a head-up display (HUD), and it’s designed to display video information in front of one’s eyes. Apple’s device would have one or two small CRT, LCD or OLED displays embedded in a wearable headset like a helmet, pair of glasses, or a visor, according to the patent description.

With two displays, stereoscopic 3-D images can be shown to the user for a comfortable, immersive viewing experience. The HMD could also be used for augmented reality, transmitting a transparent image superimposed on the world in front of you using reflective mirrors.

The patent description also mentions that video and image information could be received from a portable external source, like an iPhone, which could divide the images into one frame for each eye.

Google’s patent is very specific to Google Glass — it’s for a wearable display with an integrated finger-tracking input sensor. Apple’s on the other hand, seems pretty broad, covering a variety of head mounted display technology implementations.