Google Glass is just the beginning. The search giant’s smartglasses are in the headlines, but numerous other players are also looking to cash in on what’s expected to be a boom in eyewear that puts virtual and augmented reality face-front.

Smartglasses overlay digital information onto the wearer’s view of the real world. Usage scenarios are limited only by developers’ imaginations. Google Glass has apps for search, navigation, photo capture and sharing, to name a few. Commercial possibilities include enhanced vision systems for use in manufacturing, engineering, health care and other industries. A surgeon could have all of a patient’s vital information literally in front of his eyes while operating, for example.

There’ll be no shortage of smartglass systems in as little as one to two years. Research firm Gartner says there are about a dozen companies with products in the works, many of them ready for prime time. There could be as many as 10 million smartglasses sold worldwide by 2016, if software developers can come up with appealing applications that provide wearers with useful, nonobvious information about their surroundings, according to IMS Research, which defines smartglasses as “wearable computers with a head-mounted display.” Without good apps, the number of smartglasses sold could number only about one million by 2016, IMS adds.

“This stuff is bubbling up and it’s going to happen,” says Trae Vassallo, a partner in venture capital firm Kleiner Perkins Caufield & Byers, which has joined with fellow firms Andreessen Horowitz and Google Ventures to fund smartglass app development. Vassallo sees big potential: Kleiner Perkins’s investment will “depend on the quality of the ideas and the entrepreneurs.”

One such company is Rochester, N.Y.–based Vuzix Corp. Its M100 Smart Glasses, now shipping to developers, can run any existing Android app. CEO Paul Travers says developers are building augmented reality (AR) apps for the M100 in areas like fitness, navigation and gaming. “There will be a lot of people in the consumer space that will like these gizmos,” Travers says.

Like Google Glass and most other smartglasses, the M100 has a built-in video camera that projects an image of the real world onto an eyepiece that is essentially a prism. This so-called “wave guide” approach lets developers layer information and graphics into the wearer’s view. Advances in optics and microprocessors fueled by the smartphone revolution are what’s behind the expected boom. “The killer app for all of this are things that allow immersive AR with sensors you can fit in a phone,” says Dan Small, a research principal at Sandia National Laboratories, which has conducted extensive research into augmented reality for the military.

There are limitations: Both Google Glass and the M100 are monocular systems that use a single eyepiece to deliver an augmented field of view of about 14 degrees. Humans’ natural field of view is roughly 180 degrees, so there’s a keyhole effect.

Some manufacturers are developing binocular systems that resemble conventional sunglasses, in part to achieve a wider field and 3-D viewing. Israel-based Lumus makes AR shades that wouldn’t look out of place at a ski resort. “Google is basically a beam-splitter technology. Looking through that, your view of the world is skewed,” says Lumus business development manager Ari Grobman. “We’re giving you a pair of glasses and overlaying information on that.” He adds Lumus is in licensing talks with several major electronics companies. “We’re hot and heavy in terms of pushing into consumer applications.”

Also taking the binocular approach is Epson Corp. Its Android-powered Moverio BT-100 smartglasses give users the impression they are looking at information on an 80-inch screen through a 23-degree field. Being binocular “is very critical because it allows you to overlay 3-D content in the center of your field of view,” says Eric Mizufuka, new products manager at Epson.

Epson, a division of Seiko, is targeting the commercial market. Partner Scope Technologies has created BT-100 AR software for use in industrial training.* One of its apps overlays images of tools that the wearer would need to fix high-tech equipment, and shows where the parts should go. “We can take someone who’s been working at McDonald’s and turn them into to the equivalent of a worker with 30 years training on that machine,” says Scope founder, Scott Montgomerie. Other companies developing smartglasses include Olympus, Sensics and AR contact lens developer Innovega. Microsoft and Apple, which holds AR patents, are also said to be eyeing the smartglass market.

Experts say today’s optics and chip technologies are for the first time sufficient for functional AR. What’s needed to deliver fully immersive virtual reality or AR experiences, a la The Matrix, are breakthroughs in tracking technology. To track head movements, AR glasses need fast internal sensors, or an external system. The slightest lag can be disconcerting. “Humans are very adept at picking up latency,” says Sandia’s Small. “The problem is that sensors don’t track like chips do with Moore’s Law.”

Still, it’s expected that the sight of smart-bespectacled workers and consumers won’t be uncommon within a year or two once prices hit the sub-$500 mark—Google Glass prototypes sell for $1,500, if you can get them.

Widespread smartglass use will raise a host of privacy and regulatory issues. “We’re already hearing the term ‘glassholes’,” says Gartner’s Angela McIntyre. And you thought the jerk with the cell phone was bad.

*Correction (04/01/13): This sentence was edited after posting. It originally referred to Scope Technologies as Scope AR.