Your rear view mirrors are essential for allowing you all-round observation. There are three mirrors; the internal rear view mirror and two side mirrors – one on each door. The mirrors are designed to minimise areas around the car that cannot be observed in mirrors. These are called blind spots.
Difference Between Side Mirror and Rear View Mirror
To help maximise the observational area around your car, your side mirrors are curved. These are called convex mirrors and provide a wider viewing angle each side of your vehicle. Unlike the curved glass of the side mirrors, the internal rear view mirror is made from flat glass.
It’s important to understand these differences because it changes how you observe objects in the mirrors. Due to the internal rear view mirror being flat, objects that you see in this mirror represent an exact reflection of what’s going on behind you; the objects are the same distance and size as you see in the mirror.
The benefit of the side mirrors being convex means you get a wider view of each side of the car helping to reduce blind spots. It is important to understand however that due to the mirrors being curved, objects in the side mirrors are closer in reality than they appear in the mirror. So whilst a vehicle may appear to be far away in the side mirrors, they are in fact much closer.
The next time you sit in a car, while the car is stationary, find an object that you can see in the internal rear view mirror and a side mirror. Then compare the differences in size and apparent distances.
Due to this apparent difference in distances, it’s always important to check mirrors in pairs. Using the internal rear view mirror and a side mirror helps to determine a more accurate estimate of distances from objects.