The eyes are the windows of the body, and they are important sense organs in constant use in – everyday living. Normal vision is essential to safety, as well as comfortable living, and every precaution must be taken throughout life to guarantee that the eyes will give maximum service for as long as possible. With care and commonsense, they will serve their owner well.
However, if injury or disease occurs, prompt medical attention is essential. Some conditions may arise that could impair the vision, and the earlier these are attended to by the doctor, or an eye specialist, the better.
It is far better to see the doctor too often than run the risk of failing to have an examination carried out when it may be necessary. Injuries to the eye should be carefully watched, and such injuries as blows from tennis balls and similar missiles (occurring with greater frequency in recent times) must be checked out promptly, even if symptoms are not immediately apparent. Often without the person being aware of it, deeper injuries such as retinal detachment may be sustained, and left untreated this could severely affect vision later on. Any eye injury must be adequately attended to, whether it be a simple foreign body, or a deeper one, superficial eye injuries from chemicals, or obvious disorders of any part of the eye and surrounding parts.
The eyes are located in the bony orbits in such a way as to give them maximum protection from external sources of trauma. These act as good defense against larger missiles, for the protruding parts of the orbit are staunch guardians. However, they do not protect against smaller objects, such as flying bits of glass, stone and squash and golf balls. For protection against these hazards, the eye relies chiefly on the rapid reflex movements of the eyelids. These can react with incredible speed, and often protect the eye from outside injury.
Even so, every effort must be made to keep the eyes free from potential sources of injury. If there is any risk, either at work or play, then suitable protection is advised.
The eye is usually likened to a superbly designed camera, when people want to explain how we can see. However, to understand fully how the outside world can be viewed inside the tiny chamber of the eye, one has to go back to basics. The best way to think of light is as a transmitting medium. From whatever source, it bounces off objects in all directions, carrying with it the possibility of the objects being seen. The other important thing to understand about light is that although it usually travels in straight lines, it can be bent if it passes through certain substances, such as the specially shaped glass of a camera lens, or the lens made of tissue in a human eye. Moreover, the degree of bending can be precisely controlled by, the shape in which a lens is made. Light can, in fact, he bent inwards, or concentrated, to tiny, but perfect images of much larger objects.
Third Dimension Another important reason is that when both arc used together, the sense of depth (the so-called third dimension) is possible. Normally one eye will see objects in two dimensions, namely, length and breadth. But when the second eye comes into action, the same view is gained from a slightly different angle. This means that two pictures are received by the two eyes. However, when these are conveyed to the brain, they are automatically merged into one, and the added dimension, depth, is given.