A brief scientific excursion
A person’s ability to react appropriately at high speed or in dangerous situations is directly related to their visual capacities. In the same way, balance is related to eyesight because the cerebellum constantly correlates the information from the eyes, the organs of balance in the inner ear, and the body’s kinetic sensory cells.
When vision is impaired by dazzle or darkness, the conditions for precise motion and coordination are automatically affected.
Since humans can move only relatively slowly under their own power, evolution has not adapted their eyesight to quick changes between light and dark; they respond very slowly.
In our motorised age a further problem is that humans have a whole battery of self-protective reflexes that are triggered when travelling at a high, potentially life-threatening speed.
For a walker there is no danger when a hare or a tractor suddenly crosses their path ten metres ahead. A motorcyclist, however, can only cope with this situation by mobilising all defensive reflexes and stress hormones.
Thus, a person can only react adequately when they have a clear overview of the situation and are not distracted and riding under the influence of higher stress hormone levels.
How much our perception changes becomes clear when we imagine travelling at 160 kph, first on a wide motorway and then on a narrow tree-lined country road. Due to trees and bushes our range of vision changes and the light starts to flicker.
These irritations are a strain on our concentration, and dangerous.
Most notably it is the unnaturally quick transitions between light and dark that reduce our otherwise remarkable coordination abilities when riding at speed.
This is made worse by the fact that our eyesight only works to its full capacity under average daylight conditions. As soon as the light is glaring or too dim, our brain signals danger and forces us to slow down by rising the ‘anxiety hormone level’.
Basically, then, the problem is that our eyes cannot adapt quickly enough to changing light conditions.
Up to now sunglasses, hinged sun visors or tinted visors have been used to protect the eyes from dazzle.
These filter the whole of the incoming light, and therefore reduce the scope of our vision. The pupils have to be open wide to let in enough light. This means that with sudden dazzle or when entering a tunnel or forest, the rider will see even worse. Whenever the light conditions are variable or the sun is not at its zenith, such devices are more of a hindrance than a help.
The solution for this problem is an anti-dazzle visor that keeps the incidence of the light on the retina within an optimal range even under varying conditions. Within a fraction of a second any sudden dazzle has to be reduced, so that the rider’s concentration is not broken.
As a rule, the body reacts on reflex when suddenly confronted with an unforeseen situation. These reflexes are not controlled by our will; they happen automatically. A situation in which a rider is suddenly dazzled is such a case. The head will duck or turn away suddenly.
The SUNAX sun visor exploits this reflex reaction positively. When the rider ducks their head they automatically look through the sun visor and the danger is eliminated. The road in front can be clearly seen.
Motorcyclists who want to improve their performance, whether on or off sunlit racetracks, need a solution to help their eyes cope perfectly with varying light conditions.
SUNAX is equipped with a light filter which eliminates precisely those light frequencies that distract the rider. Recognition of traffic lights is unaffected.
Since the visor is perfectly positioned at the top of the field of vision, it ideally covers exactly the area where most of the dazzling light comes from, eliminating the most common cause of visual distraction.
Unlike conventional sun visors, the bottom edge of the SUNAX anti-dazzle sunshield is also shaped to eliminate distortion.
In normal daylight conditions, SUNAX puts the eyes into semi-shade. Distracting light from above and from the sides is reduced and the rider’s coordination benefits considerably.
On shady stretches of road, the rider’s vision is absolutely free, and at any sudden dazzle the filter takes away as much glare as is needed to maintain concentration.
After a brief period of adaptation the eyes get used to the wider perceptive ability made possible by the SUNAX sunshield and use it automatically. The cerebellum integrates this new potential into its reflex patterns. After a just a short while you will not notice wearing a sun visor at all – until you realise how easy riding into the sun has become.
Of course, sunglasses or the like are a pleasant way to reduce eyestrain, especially in glaring sunlight. A SUNAX, however, which is permanently fitted in your helmet, is always there when you need it - especially for helmets that are not really suitable for sunglasses.
Dr. Gernot Heine