Re: Bright lights

Frank Krygowski wrote:
On Dec 21, 2:15 pm, incredulous 2 <travis.ha...@xxxxxxxxx> wrote:

Do the HID lights for bikes especially promoted for off-road and
trail night riding include much in the way beam shaping? I have the
impression they do not, lowering the cost of entry into the business
by requiring little of the precision engineering that might required
for that.

I think you're correct. I imagine the technical skills needed for
good optics are a lot less common than those needed to assemble light
sources (LEDs, HIDs, halogens), batteries, and housings.

- Frank Krygowski

The off-road application doesn't want/need beam shaping. What you want is an even flood that doesn't introduce artifacts. You are trying to spot bumps and holes which get harder to discern if the beam has bright and dim spots. The standard multi-faceted reflector (MR) halogens are pretty good in this respect, that's what the reflector is designed for. "Orange peel" reflectors on the new high power LED flashlights perform the same function. You want to collimate (to limit spread) and diffuse (to even out) slightly.

Many of the popular low power bike lights used simple symmetrical reflectors with plain lenses (like Bell Vistalite). They throw very uneven (usually ring shaped) beams, like old Ray-o-Vac flashlights. Others, like the Cateve Micro, have shaped reflectors and some fresnel type elements in the lens.

Any high power light has to use a heat resistant reflector, which probably makes tooling costs large for a complex shape. Maybe you could get by with a simple reflector & a more complex lens (like old sealed beams), but that would be a road specific version of an off-road light, I'm not sure how big the market would be.
.

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