THE PHYSIOLOGY OF EYESIGHT
Seeing is an extremely complicated procedure. Rays of light go through the cornea very quickly. Being broken at the bulge of the crystalline lens of the eye they get through the vitreous body and reach the macula at the retina of the eyeground. This place is about 1.5 - 2 sq millimetres big, this is the region of keenest vision.
The light-sensitive receptors turn the impulses of the rays of light focused here into biochemical information that get to the visual area of the brain through the retina. Information is co-ordinated and becomes a clear picture. (1st illustration)
In case of short-sightedness rays of light are focused in front of the macula.(2nd illustration)
In case of far-sightedness rays of light are focused behind the macula. (3rd illustration)
To see exactly what is in front of our eyes we have to scan the whole picture. This is done by moving the eyeballs here and there so that the rays of ligth carrying the information aim at the eyes always from a different place. Normally the eyeballs are moved 50 times per second. The quicker the eye-balls move, the keener the vision.
When a new object gets to the field of sight, the brain moves the focus of the eyes to and fro until it finds the optimal sharpness. If it doesn't succeed, ocular muscles are left at the starting state bringing on dim sight. This mainly happens to loose ocular muscles. The eyes need exercise, the rythm of laxity and tightness. Wearing glasses is the most popular method for improving the impairment of sight. Glasses work instead of lazy ocular muscles.
At the beginning of the century Dr Bates, the American doctor proved that the normal operation of the eyes can be restored.
Different eye-trainings are recommended (Koplakov, Shneider system) but quite few people choose them due to lack of time, patience and will power.