The last paragraph of Mr. Kelsey’s letter in December’s edition, which slated head-up displays in cars in no uncertain terms, made my electronic engineering hackles rise! I think I can speak with some authority on the HUD principle as until last month I was involved with producing such a system for a fighter aircraft.
Although there is a .world of difference between the state-of-the-art, all-singing all-dancing aeroplane system which projects all information pertaining to the plane’s performance, location, etc., down to what the pilot had for breakfast, and the relatively simple demands of an automobile system, the great benefit of both is the continuous presentation of information without the need to divert one’s attention from the outside world—the speed, oil pressure, temperature or whatever is, by the optical properties of the HUD, effectively “written” onto the outside world, whether it be the back of the lorry 20 miles ahead or a range of hills 10 miles away.
The difference between the HUD display and the “reflections in the windscreen” of Mr. Kelsey’s letter is that while the latter is distracting and ill-defined in shape, focus and position, the HUD display is perfectly focussed at infinity, of controllable brilliance and position (and could in fact be directed to those parts of the windscreen just outside the driver’s normal zone of vision, e.g. just above the end of the bonnet)—in fact, the presence of a HUD would make eradication. of spurious reflections more important still.
I must admit to not having the benefit of personal experience of such a system in a car, hut I am particularly adversely inclined to chopping holes in the dash of my 1947 1.1/2 Hive Riley to experiment with schemes aimed at modern metal boxes!
Long live Motor Sport, now in its 50th year, and the Riley RM Club in its 5th!
Woodley Glen Crawford