Students exploit optical phenomenon to create 48-inch multi-touch surface

A not-quite-new but still impressive emerging technology, using light refraction and optical sensors, multi-touch computing is close to 'Chapter 2' of the development cycle with the exploitation of an optical phenomenon. Article
Written by Zack Whittaker, Contributor on

A group of engineering students at the University of Waterloo have recently completed building a 48" multi-touch device, which could potentially rival the Microsoft Surface device, by exploiting an optical phenomenon.

The device is a massive multi-touch input and output screen, very similar in usage to a Microsoft Surface device but with a very different underlying technology. It was constructed during a fourth-year design project at the university. Running Windows 7, the first operating system to really utilise multi-touch technology, the input and feedback are impressive from the very start.

Although not an entirely new concept, the surface technology uses frustrated total internal reflection (FITR) where light reflects off the surface of an object such as prisms or fibre-optics. A real-life example would be to hold a glass of water and seeing the impression of your fingertips on the surface of the water.


In simpler terms of how FITR and indeed the device works, as described on their announcement post:

"If you shine light into the side of a sheet of acrylic, the light will be trapped inside due to total internal reflection. Now when you touch the surface, it 'frustrates' the light at that spot and so light escapes. You use a camera to capture this image and [through mathematics] figure out where the finger was pressed."

Using FITR in this way isn't new as was displayed by Jeff Han at the 2006 TED Conference in California. Multi-touch computing was being experimented upon in the 1980's and since then, this concept isn't the first FITR-based multi-touch device created.

What surprises me is the sighs and sounds of disbelief in the audience of the Jeff Han demonstration whereas now, we consider multi-touch technology as firmly embedded into our lives - the iPhone being a prime example.

But it's still so damn cool.

What I am most proud of is the contributors to the blog where this is mentioned involve women in this engineering project.

Not only that, the university actively encourages participation of women in 'non-traditional' degree subjects, and clearly praises them when they are proud of the work and research they accomplish.

With female students clearly being as intelligent as they are to complete a project such as this, it again exposes the question of the glass ceiling in the IT industry. Even though I still believe the old boys network plays the major role in limiting women into success of higher paid jobs and those with greater responsibility, this will most definitely change when the old boys running the show either die or retire. Literally.

Editorial standards