Motorists are only just realising the important role of black dots fitted on every petrol, diesel and electric car windscreen on the road. A thick black strip followed by a series of black dots is placed around the outside of car windscreen glass with the simple feature having an important safety function.
Despite what many may believe, TikTok account @interestingengineering explained the dots are not just in place to look nice. Instead, the black enamel strip and the dots regulate temperature to ensure motorists can see properly out of their windscreen at all times. While travelling at high speeds, having a clear picture of the road ahead is vital to avoid contact with other vehicles or hazards.
The experts said: “Why do car window edges have dots? if you spend enough time commuting, you’ve probably noticed them too. It’s not actually just for cosmetics and the reason behind them is genius. The black tint on the edge of the window is called a frit.
“Its there to prevent ultraviolet sunrays from damaging the adhesive that glues the window to the frame. But that doesn’t explain the dots. Well black is the colour that absorbs heat the most. Those half-tone dots are there to prevent a sharp thermal change between the frit and the glass that might cause optical distortion.
TikTok users were blown away by the revelation, with some shocked they had finally learned the true reason behind the feature. One TikTok user simply said: “I’ve been wanting to know this for so long thank you.”
Meanwhile, TikTok user @Tunna Pro said: “After 15 years I finally know.”
Experts at AutoGlaze confirmed that frits play an important role in improving the quality of the image through the windscreen glass. They explained that a phenomenon called ‘lensing’ tends to happen when the frit band heats up much faster than the windscreen glass.
They said this could make “straight lines look curved or bowed inwards toward the centre”, explaining the black dots help lessen this by dissipating the heat and spreading it out more evenly across the surface.
However, the frit also has an important second function with the strip ensuring the glass remains stuck to the vehicle and doesn’t come loose.
They said: “They help preserve the urethane sealant used to bond the glass to the frame. They use the black enamel outside the windshield to block the sun’s ultraviolet rays from melting the adhesive underneath the band. This keeps the windows firmly glued in their place.”