A row is developing among car enthusiasts and road users about the potential risks of super-bright headlights.
The headlamps - called HIDs and commonly referred to as bi-xenon - are much brighter than traditional headlights and are sold as a safety feature. But some road-users claim they are often dazzled by the lights, making pedestrians and cyclists difficult to see.
The man behind a campaign trying to get the lights better regulated is Ken Perham.
Mr Perham has been a night-time London cabbie for 38 years. During that time he says he's seen the good, the bad and the ugly when it comes driving.
It has made him passionate about road safety, and it's what has led the 60-year-old to launch an online campaign, called Lightmare.
The campaign is demanding better regulation and safety testing of what he claims is a new menace on the roads - High Intensity Discharge (HID) headlamps.
"Without a doubt, the lights are intimidating you so badly that you have to change the way you drive and that isn't right," he said.
"It's just vehicle after vehicle after vehicle, with lights that look like they're on full beam when they are actually on dip, they're that good."
The law states vehicle lights must not be used in a way that dazzle other road users. Not surprising when one considers that dazzling headlights accounted for 365 road traffic accidents in 2009, three of them ending in the loss of life.
HID headlamps are at least 50% brighter than traditional halogen headlights and tend to be found on higher-end cars.
Halogens give off a soft yellow-tone light. HIDs or bi-xenons give off a white-blue light and show up much more of what's ahead. That is the reason many drivers who have them, like them.
'Glare and discomfort'
Mr Perham, who is being backed by the Driving Instructors Association and the British Motorcyclists Federation, isn't worried about the drivers who have HIDs.
It's those on the receiving end that he is concerned about. He claims that drivers with halogen lights can be so dazzled that other road-users could be at risk.
And that's a view backed by some eye experts, including Geoffrey Roberson from the Association of Optometrists.
"They [drivers with halogen lights] are not going to see as well or as far because their headlamps aren't as powerful - and they are going to have extra glare and discomfort that's produced by the HID headlamps.
"The consequence of that, maybe, is that they are less able to see pedestrians, cyclists, that sort of thing," he said.
Mr Roberson added that there was also evidence that, at 60, Ken's age could be making his problem with HIDs worse.
"We know the older age groups suffer more from glare-related problems so [as HIDs are brighter] they will get more dazzling glare."
Mr Perham, however, remains convinced the problem is not unique to older drivers.
But Paul Everitt, from the Society of Motor Manufacturers and Traders, dismisses the claims.
"High intensity lighting [headlamps] have been solely developed to improve road safety - they are part of what is a quite sophisticated lighting system.
"They are designed to ensure that the light is focused on the road. I think glare is a problem for all road users so I don't buy that [HID headlamps] are more dazzling, or more likely to dazzle, than any other headlamp."
Car makers say HIDs meet European standards and go through extensive testing by manufacturers.
Even so, Mr Perham remains unconvinced and says he and his supporters will continue their campaign.