Inside your eye, you see with a series of receptors called rods and cones. There are about 20 million rods per eye which measure movement and contrast. They are responsible for your peripheral vision and have a limited response to colour which we will look at in a minute.
There are about 6-7 million cones which measure colour and because of their faster response to the brain give more detail. Due to this sensitivity, the eye is in continual motion building up a picture of what is happening. This is what we want our learners to do.
These colours to which the cones respond are red 64%, green 32% and blue 2% which are the primary colours. This gives us red for danger, green for safety and blue for authority. Yellow is made up of red and green. From this, we now have the colours of the traffic lights and road signs. The rods in our eyes have no response to red light. This means at night when our eyes have adapted to the dark, a red warning light is not going to wash away the rest of our vision. Because there is some response to blue from the rods we become very aware of blue lights from the emergency services.
Eyes are sometimes described as windows to the soul. A professional eye examination can also be a window to good health. These checks are capable of detecting a range of conditions such as high blood pressure. They should be done at least every two years. Remember your eyes and vision are key for driving so have a think, when were yours last checked?