Text in a car’s rearview mirror

Jaroslav Kores, Ph.D.

Text in a car’s rearview mirror (Source: © ElenaKyrylova / stock.adobe.com)

Why is the ambulance sign on an ambulance reversed when looking in the mirror and it is clear that the sides of the displayed object do not change — what is to the right in front of the mirror is to the right behind the mirror.

A convex mirror is used in a car’s rearview mirror — this is the reason it always creates a reduced and inverted image. But the image that is created is reversed. If you want to shake your right hand with your image in the mirror, you will see for yourself. From our point of view, the hand is on the right, but in reality one would shake your hand from the left. If you take the Ambulance sign in front of the mirror, you will see that the letter A is at the end (read from left to right) and the letter E at the beginning. In order for drivers to quickly see who is following them when looking in the rear-view mirror, the inscription on the vehicles of the rescue service or fire brigade is mirror-inverted.

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