Hands together for helpful heads-up displays

Vital information is displayed on BMW's heads-up display. Photo / Supplied

A bouquet to heads-up displays, after recent snowy launch drives in Europe underlined how valuable this technology is.

It projects information, such as your speed and the next satnav instruction on the windscreen ahead of you.

Heads-up displays first appeared in military aircraft, and car applications use a similar system in which a small projector reflects the image off a see-through coating on the windscreen.

The image appears to float just above the bonnet - on some models you can adjust its height to suit.

That means you can see vital stats, like whether you're speeding, without taking your eyes from the windscreen. It's especially useful when your concentration is already stretched in busy traffic or poor weather conditions. The display's focal point - how far away your eyes think it is - sits sufficiently far from the windscreen that those who wear reading glasses don't have trouble refocusing when flicking their eyes to the instruments.

Such displays show only important information and complement the instruments. So on the recent Portugal launch of BMW's 5 Series, the complicated motorway junctions were clarified as we negotiated them, while the map of our next few kms remained on the primary instrument screen.

HUD systems are not yet available on mainstream cars though mainstream brands do use the tech - GM (badged Holden locally) first fitted it to a road car in the late 1980s.