Is it just you, or are headlights brighter than they used to be?
No, it’s not just you.
LED (light-emitting diode) headlights are increasingly replacing the previously popular types of lights used for vehicles — halogen and high-intensity discharge (HID) lights — as the go-to.
And you’re likely noticing the difference.
Nearly a year ago, General Motors recalled several hundred thousand of its GMC Terrain SUVs after the National Highway Traffic Safety Administration found the vehicles’ headlights could make it harder for oncoming drivers to see.
So what gives?
One expert, Matt Kossoff, founder and chief product officer of The Retrofit Source, a vehicle light distributor, tells the New York Times headlights have “absolutely gotten brighter.”
The popularity of LED headlights can be attributed to a few advantages they have over previous types: they last longer; they are generally energy efficient; and they look “newer.” Because they debuted among luxury vehicles, they may also be perceived as higher quality.
Mark Rea, professor at the Icahn School of Medicine at Mount Sinai in New York, explains that even though LED headlights are regulated the same way as other types, LED lights feel brighter to human eyes for very real physical reasons. Rea, who served as director at Rensselaer Polytechnic Institute’s Lighting Research Center for over 30 years, told Slate that when headlights are tested, they’re measured in units called lumens, which measure how parts of the eye are affected by brightness.
As Rea explained in previous research, human eyes are more sensitive to higher wavelength red lights than lower wavelength blue lights. This means that when LEDs and halogen lights are being measured, LED brightness increases and still retains the same measurement as that of halogen lights.
“Imagine a car with two headlights: one halogen, one LED. They’d both meet the requirement. The light meter would say they’re the same but the LED would look 40% brighter,” Rea told Slate.
In terms of lumens, Car and Driver reports LEDs can have between 9,000 and 10,000 lumens, while HIDs have around 8,000. Halogen lights measure even lower, the outlet says.
Other factors could also be at play. In conversation with Popular Science, Matthew Brumbelow, a senior research engineer at the Insurance Institute for Highway Safety, said glare can be caused by “unintentional” misalignment of headlamps, which he says are “near the end of the assembly line” when factories are “just trying to crank vehicles off.”
And if you’re also wondering whether headlights seem higher than they used to be, you’re also not mistaken.
“Tall pickups and SUVs and short, small cars are simultaneously popular,” Daniel Stern, chief editor of Driving Vision News told the New York Times in 2019. “The eyes in the low car are going to get zapped hard by the lamps mounted up high on the S.U.V. or truck every time.”
Stern also said that headlights have also gotten smaller and that “intensity appears brighter” when it’s coming from a smaller device versus a larger one.
Given all these factors, you may be wondering: Are LED lights actually any better than halogen or HID lights?
Interestingly, Consumer Reports said in 2019 that testing showed that LED headlights, while being able to produce “brighter, whiter light” than halogen headlights and increase side-of-the-road visibility, did not produce better visibility in the road in front of a vehicle.
“Even with the new technology, low-beam headlights don’t always provide enough forward seeing distance for the driver to react to an object in the road and stop in time,” said Jennifer Stockburger, director of operations at CR’s Auto Test Center.
What’s being done?
The NHTSA made a final ruling in February 2022 to allow automakers to install adaptive driving beam headlights on new vehicles. The ruling amends Federal Motor Vehicle Safety Standard No. 108., which is the rulebook for headlight brightness.
Adaptive driving beam headlights, also known as “smart headlights,” automatically adjust brightness for oncoming drivers. In many places overseas, these are already the standard.
“Our headlamp standard balances two important, and competing, interests — adequate forward illumination so that drivers can see at night and limiting glare to other drivers. Adaptive driving beams offer exciting safety potential to optimize headlamp systems so that seeing distances can be significantly improved for drivers by using upper beam intensity in areas where no other vehicles are present, and also limiting intensity to lower beam limits where drivers may be glared,” an NHTSA representative told Nexstar. “NHTSA believes this approach will improve drivers’ ability to detect vulnerable road users at night without increasing glare.”
Currently, the Soft Lights Foundation, an activist organization aiming to “ban blinding headlights,” has over 37,000 signatures toward its 50,000 Change.org petition goal. According to the foundation, the petition would urge the NHTSA, the U.S. Department of Transportation and U.S. Congress to “properly regulate LEDs as spatially non-homogeneous, directed energy radiation.”
Soft Lights founder and president Mark Baker recently gave an update on the petition, imploring supporters to contact their congresspeople to ask whether the U.S. Food and Drug Administration is working to further regulate LEDs on the basis of optical radiation hazards. Baker points to the FDA standards for visible radiation, which is set to “wavelengths of greater than 400 nanometers but less than or equal to 710 nm.”