Side mirrors, door mirrors and wing mirrors: they’re all the same thing and help you see behind your vehicle and to the sides of it. They became popular on cars from the 1960s as traffic increased, even though they are useful for reversing and changing lanes.
Modern mirrors frequently have built-in indicators, and on some cars they contain a small light to warn the driver that another vehicle is in their blind spot (blind spot monitoring). Almost all cars’ mirrors are now electric, containing motors to allow for remote adjustment.
The problems with side mirrors
- They create a lot of drag (between 2-7%) which increases fuel consumption
- They create wind noise
- They are heavy – added weight on the car increases fuel consumption
- To look at them the driver needs to take their eyes off the road
- They need to be individually adjusted for each driver, causing wasted time readjusting them a vehicle is driven by more than one driver
- People don’t know how to set them effectively and still leave blind spots.
New technology
Improvements in technology have meant that producing a camera and screen is a negligible cost. Most new cars now come with a reversing camera and internal screen and some cars feature cameras on the wing mirror and front grille to give different angles that might be useful for other manoeuvres. The 2013 Honda Accord NT was offered with an optional camera on the passenger side mirror that projected an image from that mirror onto the screen in the dashboard when the indicator was activated.
It’s possible for a camera-based system to produce a wide, seamless view from one side of the car, around the back and to the other side, displayed on a screen. The cameras can be tuned to balance an image so that vehicles with headlights approaching from the rear don’t just seem like to intense white dots. Audi is already using a system in its R18 LMP1 racing cars. Sensors will act as a backup, detecting vehicles in blind spots as they do now. Many vehicles will parallel and reverse park themselves and therefore mirrors are not required for these manoeuvres when a camera could be employed instead.
Some countries, such as the USA, mandate that mirrors must be installed on all vehicles, therefore legislation would need to change. While companies such as Tesla have displayed concept models with cameras, the production models have included wing mirrors. Things are changing with the NHTSA approving GM’s rear-view camera mirror recently, and there is a panel working on mirror use in these situations.
The switch to screens rather than mirrors could take some getting used to. Drivers are familiar with how a mirror distorts the image, and are less so with camera lenses. If the cameras go wrong they are likely to be more expensive to replace than a mirror. The smaller surface area of a camera lens is easier to cover in dirt, and would be as prone to condensation and therefore rendered useless.
Read how to set your mirrors correctly.
Darren is an expert on driving and transport, and is a member of the Institute of Advanced Motorists
