Apple Inc has acquired Metaio, a German company which makes software that melds the physical world and computer-generated elements into video displays, according to a corporate filing that has surfaced.

The terms of the deal were not disclosed.

Metaio's augmented-reality software is used in applications in retail, industrial and automotive markets.

It is found in virtual product showrooms and in manuals by retailers such as IKEA. It has also created visual guides for repairing complex industrial or automotive equipment.

Augmented reality is software that overlays text or graphics on real-life images and objects, typically in video. The result can be viewed on television displays, smartphones, tablets or dedicated eye-goggles.

It differs from virtual reality, which replaces real-world views with more or less completely simulated ones.

A document filed with a Munich court showed that Apple is now the company's sole shareholder.

Metaio's previous investors included Westcott LLC, the investment vehicle of entpreneur Carl Westcott, the founder of floral delivery firm 1-800-Flowers, and Atlantic Bridge, a Silicon Valley-based growth equity technology fund. Neither firm was immediately available to comment.

Metaio executives didn't respond to requests for comment and Apple declined to comment. "Apple buys smaller technology companies from time to time, and we generally do not comment on our purpose or plans," the company said in a statement.

The roots of Munich-based Metaio go back to German carmaker Volkswagen, where Thomas Alt, its co-founder and chief executive, began developing augmented-reality applications in 2000.

Analysts at Juniper Research expect that augmented-reality technology used in enterprises will increase tenfold to $2.4 billion from $247 million last year.

Other companies in the emerging field include France's Total Immersion and UK-based Blippar, which last year bought Layar from the Netherlands.