Head-up display systems are useful. They enable you to see how fast you are going, how much petrol you have left and other significant information in a reflection on the windscreen, without taking your eyes off the road. BMW has fitted head-up displays into its 5 Series since 2004 and the latest system is a key part of the M5 luxury saloon, which was launched in Hong Kong this month. 'A normal driver takes a whole second to read the speed indicator in the instrument panel or to glance at the navigation device,' the marque says. 'While the driver is distracted, that is without his or her eyes on the road, the vehicle covers a distance of around 14 metres when travelling in urban areas at 50 km/h - virtually a 'blind flight'. With Head-Up Display, BMW says, the time required by the driver to assimilate information is reduced by more than a half. The virtual image projected onto the windscreen 'hovers' at eye level above the bonnet and is visible only to the driver. This display is also less tiring to the driver, BMW says. 'The brightness of the image adjusts perfectly to the surroundings, so that the eye does not have to readapt each time.' A Los Angeles-based scientific consultancy, Exponent, also gave drivers useful heads-up on parking safety this month. After a two-month evaluation of reversing systems involving 70 drivers in Ford Edges with eye-tracking systems, it concluded that vehicles should be equipped with a back-up camera system with the related display in the interior rearview mirror. 'Previous studies have shown that rear camera systems reduce reversing accidents, and that mirror-integrated rear camera displays are more effective than those in the centre console,' the company says. 'Our conclusions revealed how mirror-integrated displays have additional, significant advantages. By placing the rear camera display in the mirror, you can increase display usage, improve driver scan patterns, enhance productive gaze durations and minimise reaction times.'