The future may be in the eye of the beholder

Our window into the digital universe has long been a glowing screen perched on a desk. It's called a computer monitor, and as you stare at it, light is focused into a coin-sized image on the retina in the back of your eyeball. The retina converts the light into signals that percolate into your brain via the optic nerve.

Here's a better way: paint the images themselves directly onto your retina, and eliminate that bulky, power-hungry monitor altogether.

To paint the images, use tiny semiconductor lasers or special light-emitting diodes; one each for the three primary colours (red, yellow, and blue) and scan their light onto the retina, mixing the colours to produce the entire palette of human vision. Short of tapping into the optic nerve, there is no more efficient way to get an image into your brain.

The advantages, at least for some viewing situations, are overwhelming. If the light was scanned onto only one of your retinas, images could be overlaid on your view of real objects, giving you an animated, x-ray-like glimpse of the simulated innards of something, such as a car's engine or a human body.

Alternatively, if slightly different images were scanned into each eye, vivid three-dimensional scenes could be rendered. Gamers would experience a heightened sense of reality that LCD goggles could never provide, because the laser or LED-based system could dynamically refocus to simulate near and distant objects with realism.

The forerunners of such systems, known as scanned-beam displays, are just now hitting the market. They're moving into the automotive-service industry to help service technicians keep track of the huge and ever-changing reams of engine data precisely where and when they need them - in the service bay, as they are working on a car.

This first-generation system, from Microvision of Bothell, Washington, was introduced to auto dealers earlier this year at the National Automobile Dealer Association conference in Las Vegas.