Comment [ Microsoft calls its multitouch user interface Surface Computing "a new paradigm". We asked a British pioneer in the field to examine the claim. - ed.]

This week Microsoft demonstrated a 'multi-touch' coffee table user interface it calls Surface Computing, and it got the BBC - and some Register readers - very excited.

"The amount of time they spent working on this suggests they didn't just nick it off someone else in the last 18 months", writes Dan. "Give credit to Microsoft for being first to a commercial market," agrees Amy Wohl.

But let's set the record straight.

Microsoft's Surface Computing isn't "a new paradigm", nor is it adding any innovation to an existing paradigm. Table computing isn't a new market, either, and Microsoft's demos are years away from being productized.

In fact, according to Bill Buxton - ironically a Principal Researcher at Microsoft's own research centre - these kinds of multi-touch interfaces have been around for over twenty years. Perhaps the Surface Computing marketing guys at Microsoft should check out Bill's web site.

Moreover, perhaps Microsoft and developers like Jeff Han at NYU, who are building these 'old-school' multi-touch interfaces out of cameras and projectors, should consider the fatal flaw in their 'innovations'. This being that all back-projection interfaces are enormous. Think about it - you've essentially got a small cinema in a box behind a screen. Forget mobility and portability. Is it even moveable?

Another major concern about this pioneering work, was pointed out by Reg commenter Nick Ryan.

"Notice something about all the examples? It's only used in the dark, which is nice considering that on average it's dark only 50 per cent of the time!"

The systems developed by Microsoft and Han do indeed look pretty on YouTube, but more pragmatic developers have known for some years that a successful commercial product would have to be flat and portable. People just don't want huge cabinets in the era of mobile computing and flat-screen TV's.

I've developed several multi-touch interfaces, and I know the problems and challenges.

While Microsoft and Han appear to have been resurrecting ergonomics exercises from the past, other major players, such as Apple, Philips and Toshiba have been thinking hard about how to do multi-touch sensing without resorting to using a camera and a projector.

Apple acquired the multi-touch know-how that is going into their imminent iPhone product from the company Fingerworks , while some interesting developments have come from Toshiba Matsushita who have created a very clever multi-touch LCD display using negligible additional hardware.

Potentially even more exciting is a British company Plastic Logic who seem to have created a flexible pressure-sensitive multi-touch interactive display, surely the Holy Grail of commercial touchscreen technologies. Just last week Plastic Logic laid the foundation stone of its e-paper fabrication plant in Dresden, expected to be operational in 2008.

Multitouch: it's no cinch

A major usability problem that has dogged multi-touch computer interfaces for the last twenty five years is the lack of tactile feedback. The physical feel of the interface is something you take for granted when using a conventional 'hard' interface, such as a keyboard. And when it's not there, you really miss it, as users of virtual keyboards have discovered to their cost. This issue may not even be a 'known unknown' yet for Microsoft.

Some of Apple's recent patent applications appear to be addressing this issue. Philips, too, has demonstrated real advances - unveiling a rival coffee table system called an 'Entertaible'.

This sophisticated table-top games system elegantly combines multi-touch with multi-object sensing, so that physical objects, as well as many hands and fingers, can be tracked by the 32-inch LCD playing surface.

According to the BBC, "Microsoft said it aimed to produce cheaper versions for homes within three to five years". And despite the sterling work of the likes of Philips et al, Microsoft have also claimed to be "the first major technology company to bring surface computing to market in a commercially ready product". These conflicting statements seem to raise question marks over quite how far Microsoft have actually got. Only time will tell whether or not these demos are just smoke, mirrors, cameras and projectors. ®

Andrew Fentem has worked in and human-computer interaction research and hardware development for 15 years. His Spaceman Technologies is exhibiting a reconfigurable tactile multi-touch and multi-object tracking interface at the Kinetica Museum, the UK's electronic art museum, in London until 29 June 2007.