When riding a motorcycle, it is critical to have a healthy vision, although this is a fact ignored by most riders. Having healthy vision can be natural or corrected and together with protection for the eyes as required when driving whether a vehicle or any other machine vision is improved. This is because of target fixation which refers to the fact that a driven machine will follow the guided path of the driver. For this reason, there is a rule that points out to drivers not to look at obstacles but rather fix their gaze on the path they wish to take.
VISUAL PROBLEMS THAT ARE COMMON TO RIDERS
The most common vision problems are near or far sightedness and astigmatism all of which can be corrected through recommendations from an optician of contact lenses or glasses to wear. However, most people will ignore these defects and choose to drive machines motorcycles included with inadequately corrected visions or totally ignored conditions. However, out of the millions doing this, a significant number of them have no idea they have a condition affecting their visibility and needs correction. Deteriorating vision may be hard to notice since it creeps in slowly depending on the cause. Numerous states do recommend an eye check up every two years to check vision health by an ophthalmologist. An assessment by the ophthalmologist is bound to discover any unknown defects.
WHAT IS THE HUMAN FIELD VISION?
Since a human being has two eyes, he is said to possess a binocular vision, since the two sets of eyes work together to give a lone image and is made up of both the peripheral and central vision. The human eye has a field view in 180 degrees together with depth in perception. The central vision is a process that directs a gaze at an object to form a judgment on the distance while applying a visual field of 60 degrees which can be a further 60 degrees vertically and 70 degrees downwards. On the other hand, the peripheral vision can extend up to 180 degrees on the horizontal plane right to left and will give a vague visual feedback on the side of any direct vision.
AVAILABLE VISUAL CORRECTION FOR MOTORCYCLISTS
The two options available to correct visual impairment for motorcyclist are contact lenses and glasses of which each bears pros and cons respectively.
- Glasses are capable of protecting the eyes of the wearer from wind.
- Glass can be tolerated by everyone.
- Glasses easily fog up, but one can purchase the anti-fog at an extra cost although they aren’t 100 percent anti-fog free.
- They can distort vision albeit slightly as a result of the distance between them and the cornea.
- Glasses can be uncomfortable if worn with a helmet if they have frames that run to the ears from the side of the face but this can be overcome by purchasing the ones with flexible memory- shape and can wear comfortably with a helmet. Besides some helmets are designed with grooves that allow the temples of eyeglasses a neat slide through thus being comfortable.
- In case of an accident, glasses can add to injuries.
CONTACT LENSES (THESE ARE WORN INSIDE THE EYE AS OPPOSED TO THE GLASSES)
- Contact lenses maintain a wide visual field even with a motorcycle helmet.
- Since contact lenses are placed directly on the eye and stick there, they follow the eyes movement thus maintaining peripheral vision.
- Contact lenses don’t fog.
- They are in contact with the cornea thus no distortions in the distance.
- Contact lenses can be intolerable to some individuals.
- They do not protect against the wind, and if the wind gets into the helmet, they may dry out and as a result become irritating to the wearer.
SUNGLASSES: These can be purchased in prescriptive glasses mode and also feature anti-fog. However, when opting for sunglasses, the wearer has to be aware of the tint nature of his helmet visor. For tinted helmet visors, it is recommended to stay off the sunglasses since the two serve the same purpose and if worn together, possible judgment errors can occur especially on oncoming vehicle speeds due to the distortion effect that will result.
FOGGING AND CONDENSATION
Prevailing weather conditions will have an effect on a rider’s sunglasses, glasses and helmet visor by causing fogging and condensation which obscures visibility. Fogging up occurs when the breathed out air gets trapped inside the helmet visor although most helmets have mechanisms to counter this. However, condensation will occur only when the weather temperatures dip too low causing the fogging to condense. This can be overcome by fitting secondary visors, use water repellent products to wipe the visor, and wearing a neoprene mask. Opting to open the helmet to let out air is not advised since it can cause conjunctivitis eye problem due to the exposure to wind, dust, insects and dry out the moist membrane of the eye which makes them prone to infections from the irritation that results if not treated early. On the onset, a good cleaning with clean water or eye drops can rectify the problem but when it advances, a lot of itching is felt, and yellowish ocular discharge can be seen to come out of the eyes. This ocular discharge sticks the eyes together until cleaned, and besides the severe itching is a risk to the rider.
EFFECTS OF MOTORCYCLE HELMETS REGARDING FIELD VISION AND SPEED
When a rider adorns a motorcycle helmet, his/her visual field is reduced to certain degrees dependent on the design of the helmet. The central vision on average is reduced at 30 degrees on vertical plane whereas below it is decreased by 50 degrees. Peripheral vision decreases between 100 to 120 degrees on average.
As a motorcycle accelerates and speed increases the field vision of the rider decreases up to 75 degrees when at 44 miles per hour and 45 degrees when at 62 miles per hour on average. However, when speeds of up to 100 miles per hour are achieved, the vision decreases to about 30 degrees.