The mirrors along with the car’s windows are for the taking of information. You need to know what is happening behind you in order to be safe and offer information to other road users. The process of using your mirrors will by virtue of your field of vision increase your knowledge of what is happening to the sides.
Types of mirror surface.
There are a number of different types of mirror surface. They are flat, concave, convex and aspheric.
Flat:
- A true picture of what you are seeing and is the type of mirror you have indoors.
- In your vehicle it is your interior mirror and sometimes your wing mirror.
Concave:
- Magnifies what you are seeing.
- These are normally shaving mirrors and not used in motor vehicles.
Convex:
- This makes smaller (minifies) what you are seeing and is normally used as a wing mirror.
- These have the danger that they make vehicles seem further away than they really are.
- They also make the speed of approach of following vehicles seem slower than it actually is.
- A convex mirror will make other vehicles appear further away and distort their speed.
- Some studies say that while the view obtained from the rear view flat mirror will compensate for that effect.
Aspheric:
- The surface changes for the purpose of increasing the field of vision.
- It will go from flat to convex and these are normally used as side mirrors.
- Flat nearest the car to show the side of the car when manoeuvring.
- Convex furthest away from the car to show more of what is happening behind
Types of vehicle mirror.
You have 2 types of car mirror. The interior or rear view mirror and the exterior or side mirrors.
The Interior or Rear view mirror:
- It is swivel mounted to allow adjustment to suit the driver.
- This will also allow for accidental knocking and there is an anti-dazzle position.
- This is flat to give a true picture of what is happening behind.
Exterior/Wing/Side mirrors:
- Normally situated on the door or the `A` pillar on modern cars but older vehicles would have had them further forward on the wing.
- They are spring mounted to allow for being clipped or knocked.
- They can be flat, convex, or aspheric depending on the manufacturer.
- A vertical line on the mirror will indicate a change of perspective i.e. from flat to convex.
- There may also be a warning that vehicles in the mirror are closer than it appears.
How to Use
They are for the taking of information to the rear of the vehicle. We tend to see through the windscreen but look in the mirrors hence the expression looking glass. Mirrors are part of any driving routine.
They are the first M in MSM routine and are part of the information overlap in the PSGA routine.
To be used for any hazard encountered using these routines. A hazard being anything that; does or may require a change of speed and/or direction. Their purpose is to know if anything is too close to you or trying to move round you.
They should always be kept clean and adjusted for the individual driver. When adjusting they should be held on the edges so as not to distort the image with finger prints.
The top edge of the interior mirror should correspond with the top edge of the rear windscreen. The edge of the mirror nearest the driver should correspond to the far side edge of the rear windscreen that is behind the driver. This is to be aware of overtaking vehicles.
The exterior mirrors should be adjusted so that the nearest edges to the vehicle just show the sides of the vehicle. The horizon should be midway in the mirror to give a long extended view to the rear. Properly adjusted wing mirrors will help with manoeuvring particularly reversing into parking spaces and the like.
A good mirror habit which includes the side mirrors will stand you in good stead.
Blind Spots
Every vehicle has blind spots, which will be dependent on the driver, his seating position and the vehicle itself. Some mirrors will claim to eliminate blind spots by increasing the field of vision. This is done with a convex mirror which will make other vehicles appear further away and distort their speed which could lead to errors of judgement.
Having checked your mirrors a shoulder glance will probably be necessary depending on the manoeuvre. If you are stationary, move your shoulders to do this. If you are moving along, a quick movement of your head is safer.
Syllabus For Learning To Drive – Mirrors: Vision And Use
© Liam Greaney
