Originally Posted by
AlmostTrick
Thanks, chaadster.
Here's my light, the Bontrager 700 ion. If you look close you will notice the top of the beam is shielded farther out than the bottom. I've also seen other lights designed in this manner and there must be a reason for it. Surely this will cut off the top spill more compared to the bottom which has a shorter shield. Maybe the difference is small and only oncoming traffic can tell the difference, but it seems to me there must be some. I think I'll flip mine just for a test.
I don’t think that tiny bit of shroud shaping will any effect on the light distribution at all; to be in shadow cast by the shroud, the viewing angle would have to be virtually perfectly perpendicular to the lens face. The only viewer who could be anywhere near that angle is the cyclist on whose handlebar the light is mounted. If those kinds of shrouds aren’t there to protect the user from glare, they are merely styling elements, because they have no impact on the distribution of light in front of the lens.