Technophiles and developers seeking the next tech breakthrough were drawn to the Dutch city of Rotterdam on Friday to hear augmented reality promoted as a way of changing their view of the world.

Unlike virtual reality, augmented reality combines real-world images with computer-generated images on a screen, usually in real time.

For example, someone holding up a mobile phone equipped with a camera, a global positioning satellite (GPS) sensor, compass and the right software, can point to a city street and overlay older images of historic buildings or streets.

Dutch company Layar is one of the leading providers of the underlying software that makes augmented reality possible.

Wouldn't it be great to stand somewhere and see what this place looked like sometime in the past? said Claire Boonstra, one of Layar's founders. You can teleport yourself to completely new locations.

Layar is available on Apple Inc's iPhone 3gs and Google Inc's Android-based mobile phones.

Boonstra showed different ways in which augmented reality can be used, such as a Beatles tour guide of London, digital artwork on city streets or a game of Pac-man on the sidewalk.

Revenue associated with augmented reality is expected to grow from an estimated $6 million in 2008 to more than $350 million by 2014, according to a report last month by Oyster Bay, New York-based ABI Research.

Augmented reality isn't necessarily new -- in fact it's been around for the past 15 years.

Broadcasters were early adopters, using digitized images to enhance television pictures (in swimming, for example). Video game makers, notably Sony Corp and Microsoft Corp, have adopted augmented reality technology as a way to create more interactive games.

What has changed is the proliferation of mobile devices with the features, processing power and connection speeds to make augmented reality more accessible and at the same time expanding the ways in which it can be used.

That has also opened the door for advertisers, who will be able to market goods and services by inserting digital images and objects that are relevant to the location and relevant to the user.

Augmented reality has the potential to put everything we have online, and layer it on to our physical experience, said William Kerchmar, one of the event's organizers.

(Editing by David Holmes)

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