Originally Posted by
DannoXYZ
Yeah, they need the e-code reflector pattern with sharp cut-off like on European cars.
Why? If bicycle lights were positioned like a car's, there might be a valid point for the e-code cut-off (not that SAE would agree). However there are several reasons why that kind of optics isn't necessary. At least not from the standpoint of impact on other road users.
Start with road position. Mechbgon demonstrates pretty clearly in this picture
Originally Posted by
mechBgon
from
this thread that we cyclists are too far away from drivers and have too little light output to seriously impact on on-coming driver. Even the e-code cut-off on lights is asymmetrical with light being cut off on the driver's side lamp but the passenger's side lamp reaches further down the road. Since we ride to the right of that passenger's lamp, we have little opportunity to cause glare problems. Our lamps are simply not that bright nor that concentrated. Most of the light is going to be along the center axis of the lamp with rather diffuse light to the sides.
Secondly, because of the lower lamp power and the slower vehicle speeds, our lamps aren't usually aimed that high. If the lamps are aimed high, the light is being wasted and not fulfilling it's primary function...illumination.
There is also the matter of cost. Optics are going to raise the cost of the lamps. With some lamps already costing $600+ for an okay light, adding optics will only add to the cost.
And let's not forget that lights were, and are, driven by the mountain bike industry. They were the first ones to notice a niche and they filled it. A light for mountain biking will work for the road but a light with a sharp horizontal cut-off won't work as well for mountain biking. Mountain bikers want the upward spill of the light to avoid overhanging obstacles on trails and a brighter, wider illumination.
And, finally, look at who is driving the portable lighting industry now. It's not bicycles. It's flashlights. We bicyclists are adapting the technology for our use but even mountain biking is a very small part of the portable lighting industry. Road...aka commuting...bicycling is and even smaller niche. There are only about 750,000 regular bicycle commuters in the US. Fewer still of those are darkness riders. That's not much of a market.