The increased brightness has come about through the use first of high-intensity gas-discharge bulbs (HIDs), which arrived around 20 years ago, and now through LEDs which are what has tipped headlight brightness over the edge. With a regular tungsten bulb, including the usual modern quartz-glass version filled with a halogen gas which allows a brighter filament without burning out, limits are set by stipulating a maximum wattage. But the new technologies use much less power, so they can be much brighter while still offering energy savings and appearing to meet the rules.

That sounds like a win-win, but it's anything but if you're being dazzled by a new-tech LED array. Which is why the UN Economic Commission for Europe is looking at ways of limiting the new lights' brightness and dazzle potential, armed with proposals from UK governmental research.

This will be good news for all, including – perhaps paradoxically – those who drive the new cars. You might assume that brighter is better from behind the wheel, but it isn't necessarily so. Recently I was driving a new Range Rover Velar at night, with LED headlights bright enough to disturb sleep patterns in the next county, but beyond the intensely-illuminated, and unusually broad, beam pattern I could see hardly a thing. It had the sharp upper cut-off usual in a dipped beam of the post-1960s era, which meant the contrast between what was lit and what was not was huge. My eyes simply couldn't decipher what lay beyond the blaze.