HTC's new patent lets you slip a smartphone into a device and watch virtual reality. Sound familiar? It should — this is how Cardboard-like VR headsets work.

HTC is of course better known for its Vive devices, tethered VR headsets that are considered some of the best VR devices available. A headset that pushes VR through a smartphone relies on the handheld to play the content. Devices like Vive and Oculus Rift use computers to host the content.

The patent for HTC, first published by Android Headlines, describes a device that is both a smartphone case and a set of VR lens. HTC's notes in its patent that current Cardboard headsets are rather big — hard to carry around as easily as a smartphone. The new patent describes, instead, a set of lenses and a frame that are foldable, "which is advantageous for users to carry around."

The new patent describes a gadget that folds up slim, like a smartphone, and can be carried easilyHTC

From the images, the new gadget appears to attach to the back of the smartphone —or any "portable device," and sit neatly folded, until someone wants to unpack the headset and open it up to use.

There are of course small foldable VR headsets already on the market, like the Pocket 360. And, as with any patent, there is no guarantee the described device from HTC will ever come to market. Instead, better bets are on HTC Vive's next device —the HTC Vive Focus — an untethered, standalone headset that's already been released in China for $600. When it comes to the U.S.? That's still up in the air.