LED lights tend to actually have a sharper cut off than traditional bulbs. In a manner of speaking- you actually see less total area illuminated, but you get better illumination of what you’re supposed to be seeing. Halogen lights have more “scatter” and hence a higher chance To accidentally blind onlookers- but a xenon “HID” in a non xenon focused housing is likely worse as it has the wrong output pattern but a higher output in general than halogen. Usually- if someone’s lights are blinding you it is for one of several common reasons-
1. Mismatch of vehicle heights. This is most common when one or both vehicles are st a modified ride height- a “lifted” truck” and a standard vehicle or a “lowered” car and standard vehicle. The lower vehicle will usually get blinded by the higher. 2. This feeds into #1 and is most common of all- poorly aimed lights. Many people don’t aim lights at all let alone regularly- and individuals and mechanics often aim lights higher than they should be as it tends to cast light farther and thus makes people feel they can see further. It may actually work too- but at the expense of other drivers vision as you blind them. A non DOT approved light housing can also cause this regardless of how the lights are aimed as the pattern is wrong. 3. Is simply elevation. As in example #1- a car which has its Windows fall below the headlights of another car is more likely to be blinded- especially at close range.
As two cars drive over changes in the road, hills, or even small bumps like railroad crossings the front and rear of the car will effectively rise or fall in relation to “level” which can cause the beams of a car to hit you in ways they wouldn’t on a level surface. These hazards exist with all types of light, but lights with higher output will have a greater sensation of being “blinded.” LED lights emit directional light. That is- opposed to halogen or other common light sources where light scatters in many directions from the source- a light emitting diode only emits light in one direction from each diode in a straight path. This can also contribute to the feeling of “blindness” as an LED will appear more intense than a bulb of comparable total output when viewed from directly in the path which it emits light.
A well designed factory LED set up will mitigate most of these factors- but when it comes to headlight aiming and ride height- only individual users can do their part as much as possible. Some vehicles- especially older ones- just have glass lines lower than modern cars, and some cars like newer cars tend to have their lights mounted higher in comparison- meaning if that is the problem there isn’t an easy fix against any type of automotive light source. There also isn’t a fox short of “adaptive” or “auto aim” headlights that can deal with all changes in elevation- and a comprehensive version of that technology is unlikely to exist in our lives- meaning that issue is here to stay more or less.
In the end- individuals can use LED lights without causing undo stress to other motorists, but there is inherent design- auto makers want their lights to be bright- buyers like the idea of having bright lights and all other things being equal will generally choose brighter lights and the idea of more safety given a choice- so the burden falls on the individual user to ensure they aren’t causing preventable distress to others.
but led headlights can fuck right off