What are those black dots on my windscreen?

03 April 2023

Have you ever checked your rear-view mirror and thought, ‘what on earth are those black dots on my windscreen?’

As it turns out, they actually serve an important safety purpose.

According to windscreen repair company Autoglaze, the black dots (which are actually called a dot matrix) help to distribute temperature evenly to reduce optical distortion or lensing.

The company explained on Reddit that this happens when the solid black band (known as the frit band) heats up faster than the windscreen glass, creating an ‘optical distortion’ that makes straight lines look curved or bowed inwards toward the centre.

The dot matrix lessens this phenomenon by dispersing the heat evenly.

The dots also help to keep the windscreen firmly glued in place by creating etches on the surface, making them rougher so the adhesive can stick better to the glass and preserving the urethane sealant which is used to bond the windscreen glass to the frame.

Aesthetically, the dot matrix balances the contrast between the dark band and the transparent glass, which can look too obvious even when seen from a distance.

As they say, every day is a school day, and we hope you have learned something new!

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Our minibus leasing contracts are flexible, with tailored payment plans to suit your budget and you can choose from a range of vehicles from 8-seater and 9-seater minibuses all the way through to 17-seater minibuses. 

To find out more, please contact us by calling 01480 220444 or emailing info@marshall-minibus.co.uk.

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