Quote:
Originally Posted by ru'
And the slide of the cylinder???
I'm not so sure they'd go to all the trouble to get a red/green light. All you'd need would be a light source and a red/green filter. No need for the mirrors etc. or the cylinder slide IMHO.
Holding a map up to the windscreen to read it sounds pretty dangerous too.
Jury still out?  |
Slide of the cylinder - it's just a masked filter to change the shape of the light beam so that there's no light scatter inside the unit. That would also explain why the matt black optical paint was used on the interior of the unit - to ensure that the polarisation of the light wasn't compromised by scattered rays bouncing around off reflective interior surfaces...?
The fact of the matter is that a lone driver WILL need to refer to either a map or directions at some point, and may not have the luxury of being able to pull over and check. The safest way to do that would be to be able to glance at the directions/map and still have you peripheral vision on the road ahead. To do that you would need to raise your document (be it directions or map) to eye level, off to the side of your head (obviously not right in front of you - bit to dangerous!!), so you'd need a light that projects from behind you, forwards. Exactly like this one does. Furthermore, you'd need a a filter/mirror set up in order to achieve polarisation of the light, and you'd need the light to be PROJECTED rather than just cast (i.e. you need a parabolic dished bulb - like the halogen lamp - rather than just a plain bulb). To fit the unit incorporating those components in the rear of the car would seriously compromise headroom in back. The only real section of the cabin roof where you don't expect a human head to be or move through is the centre, in the front half of the cabin. So logically you'd want to try and site the projector unit there. But you wouldn't get the light in the right place, at the right angle - so the best solution is the have the unit there and a slim projection chamber run along the roof and a mirror at the rear to redirect the light. All works rather neatly IMHO and I can't imagine a neater, more space-efficient solution.