Heads Up

In the last few years, head-up displays (HUDs), which project information onto the driver's view of the road, have started appearing in a few high-end cars, but one small enough to fit inside a rearview or outside wing mirror, could make this kind of display available on more cars.

A head-up display overlays information on a normal view of the road so the driver does not have to look away from the road.

 
The new projection device, developed by Light Blue Optics, based in Cambridge, UK, uses a technique called holographic projection that allows it to be put into a rearview mirror, wing mirror, or even the windshield.

Details of the prototype were presented at the Society for Information Display's Vehicles and Photons 2009 symposium, in Dearborn, MI.

Holographic projection uses constructive and destructive interference of light to make up the picture. They use liquid crystal on silicon to modulate beams of red, green, and blue laser light to create a complete image. It does not actually create a hologram, but rather uses principles of holography to create a projected image through optical interference. It could be on new cars within a few years.