The augmented reality headset from former Valve employees Jeri Ellsworth and Rick Johnson, called castAR, hit Kickstarter today with some intriguing new features.

The AR glasses, which were originally in development at Valve, were revealed earlier this year when the two were laid off and received permission to keep working on the project independently.

Their new company, called Technical Illusions, launched a Kickstarter for the eyewear today. They're seeking $400,000 (about £250K, AU$422K).

More importantly, castAR appeared on Kickstarter with a surprise: an attachment that can turn the glasses into a virtual reality device akin to the Oculus Rift.

The specs

The final castAR glasses are comprised of two small LCD projectors, a bridge-mounted camera, and lightweight plastic films in place of the heavy glass found on prototype models.

The camera looks for LED markers on a separate retroreflective surface and uses them for head tracking.

However, an attachment announced today with the Kickstarter can turn the castAR into proper augmented reality glasses that don't require the separate surface to function, or a full-on virtual reality display like the Oculus Rift.

There's also a controller, called the Magic Wand, with 3D input capabilities, buttons, a joystick, a trigger, and a removable extension piece. The full applications of the Wand are unclear, but it looks like it would mostly be used for gaming.

To that end Ellsworth told Engadget that "Oculus-style games" will be easy to port to castAR.

The Kickstarter also describes tabletop games that work with users' existing miniatures, like a virtual Dungeons & Dragons game that could be played using the headset and an included RFID Tracking Grid.

The castAR's display comes in at 720p, higher than the test models seen earlier this year, and unlike Oculus Rift it's designed to fit over users' prescription glasses.

Right now Google Glass comparisons aren't quite apt, since castAR must be tethered via HDMI and USB to send and receive video and images. But communication with mobile devices could reportedly be in the headset's future.

What's it cost?

There are numerous packages, including separate accessory purchases for under $100 (about £62, AU$105).

Full bundles with everything described here range from $189 (about £118, AU$199) to $355 (about £222, AU$374), depending on the size of the retroreflective surface you want and other variables.

Then of course there are the typical ridiculous Kickstarter options, including a $10,000 (about £6,253, AU$10,554) prototype model.

At the time of publication, the castAR Kickstarter has reached $167,000 (about £104K, AU$176K) and it's rising every second.