A 'Misty' Screen For Trade Shows

By Roland Piquepaille

In "Foggy screen points the way," Nature describes a technology invented by a Finnish company named FogScreen. But don't let you be fooled by the name, the images are not blurry, even if the screen is made of water. You can even walk through the screen without feeling wet because the company uses 'dry' fog made of plain water without any chemicals added. The idea behind the technology is similar to the one used by laser shows for musical events. And the real beauty of this innovation is its ease of use. You just replace your conventional screen by a FogScreen, and you're all set. But read more...

Here are the opening paragraphs of the article from Nature.

Forget plasma screens, here's one made out of nothing but water. Inventors have fashioned an interactive computer display from a curtain of fog.

The FogScreen uses ceiling-mounted air jets to create a vertical, turbulence-free slice of air a few centimetres thick, into which a fine mist of water is pumped. An ordinary projector can be used to display images on the resulting wall of fog.

And you can even click on this wall of fog.

When the projector is hooked up to a normal computer, the FogScreen can function much like the large display from a desktop in a lecture theatre. But, with the help of a laser-scanning system, the FogScreen also allows users to click on the watery screen itself.

Poke a finger at the screen, and the laser beams scanning the surface of the fog are interrupted, allowing the system to detect where you have 'clicked'.

Below is a photograph showing how a FogScreen could be used during a trade show or a cultural event (Credit: FogScreen Inc.)

Here is a link to a larger version of this image (579 KB).

Nature adds that these screens are based on simple technologies.

It looks high-tech, but the FogScreen relies on fairly simple technologies. Ceiling-mounted blowers create vertical sheets of non-turbulent air that flow side-by-side without mixing. High-frequency ultrasound vibrations vaporize water into tiny droplets that are pumped between air flows.

In this page about its technology, FogScreen adds some details -- but of course, this is company literature.

The basic components of the screen are a laminar, non-turbulent airflow, and a thin fog screen (or any particles) injected into and inside a laminar flow. Created this way, the fog screen is an internal part of the laminar airflow, and remains thin, crisp, and protected from turbulence.

The fog is made within the device using water and ultrasonic waves. If you hold your hands in the fog flow, the fog feels dry and cool, and your hands do not get wet.

After the screen is formed, images can be projected onto it. The screen can be translucent or fully opaque.

And with two projectors, you can project different images on both sides of the screen.

The technology behind the FogScreen products has received the U.S. patent number 6,819,487 in November 2004 under the name "Method and apparatus for forming a projection screen or a projection volume."

Finally, in "Click on air!," innovations report, from Germany, describes what you would experience at a car show if an automotive company used such a display.

Imagine a stand at a motor show featuring a new convertible. There's a screen