Two secret reasons why every car has black dots on glass windscreens

Drivers of petrol and diesel vehicles are unaware of how important black dots on their car windscreen are. Many road users are likely to believe that black dots on the windscreen are purely for aesthetics, a simple pattern to look good to the eye.

However, drivers may not be aware that the simple design has two very important jobs that are crucial to road safety. The black design around the edge of every windscreen on the road is officially known as a 'frit' Firstly, the 'frits' main job is to evenly distribute temperature across the glass to reduce the risk of 'lensing'. Too much heat in one part of the screen can reduce visibility, causing optical illusions and often making straight lines appear curved.

Experts at ASAP Windscreens stressed that the dots help to "reduce the phenomenon" and ensure clear visibility behind the wheel.

ASAP Windscreens explained: "To reduce the visual distortion of the windscreen known as lensing, which occurs when the solid black strip heats up considerably faster than the windscreen glass, causing an optical distortion of straight lines that appear to be curved or bent inwards towards the center, a 'dot matrix' or 'halftone' pattern is created.

"By dissipating and evenly distributing heat, these 'gradually sinking' black dots help to reduce this phenomenon."

Secondly, the black dot 'frit' is also an important tool in maintaining the structural integrity of the windscreen.

Specialists at NuVision AutoGlass stressed that direct sunlight could damage adhesives and the urethane sealant around the glass.

This sealant is what keeps the glass in place, meaning damage to this could see the windscreen become loose in a major safety risk.

NuVision AutoGlass said: "Sunlight can wreak havoc on adhesives, and your car’s windshield is no exception.

"The black color of the frits is not cosmetic- it acts as a shield, blocking harmful ultraviolet rays from reaching the urethane sealant that bonds the glass to the frame. It also prevents the adhesive from degrading, keeping your windshield firmly secured."

These two simple safety features are why road users just ensure they get their 'frit' repaired in the event of any damage.

Any tearing away of the 'frit' such as peeling or fading can compromise the windscreen's adhesion.

However, repairing a damaged 'frit' can be substantial with bulls likely to range anywhere from £200 to £1,000.