If you've noticed that other vehicles' headlights appear to be more blinding when you're driving at night -- you're not crazy.
More and more automakers have replaced halogen bulbs with LEDs, which produce brighter light. But do they help you see better?
Not really, says Mark Rae, a professor at Mount Sinai School of Medicine and an expert on light.
"The eye is complicated," Rae told WTAE. "It has what we call different channels. One is to protect you against deer jumping out on the road, and the other is to say, 'Oh, it's a nice, pretty blue sky day.' And those are very different processes in the brain to do that."
Yes -- LED bulbs are brighter. But the reason LEDs don't help motorists spot objects in the road more quickly than halogen bulbs do is because spotting danger and gauging the brightness of light are two different functions of the eye, Rae said.
"Since things are brighter with this blueish light, people driving think they see better because it looks brighter," Rae told WTAE. "Now, they don't detect the deer any faster, but they think it looks brighter."
A particular problem with LED headlights, according to LightAware, is that the light is not distributed evenly across the headlight's beam but is concentrated in the center. Many vehicles in Europe and Asia offer adaptive driving beam (ADB) headlights which "can actually shape the light coming from headlights rather than scattering it all over the road," but regulations in the United States have prevented the technology from being adopted here, according to CNN.
"US auto safety regulations enacted in 2022 were supposed to finally allow ADB headlight, something for which the auto industry and safety groups had long been asking for. But, according to automakers and safety advocates, the new rules make it difficult for automakers to add the feature," CNN reported.
That means it will probably be several years before ADB headlights are widely available in the US, per the report.