The use of contact lenses may offer certain advantages over the use of glasses in certain aspects that had to comment: Optical advantages: Provide a total visual field, as the mount does not interfere with vision. The person perceives objects similar in size to actual size. Therefore, contact lenses are particularly suitable for people with anisometropia (different degree in both eyes). In these... 

Ever wonder why people actually have different eye colors? Honestly, the question is not so easy to answer, because research results are still not so long ago. So why do we have different eye colors? If you believe the research, there is the color blue as the eyes only for 6,000 – 10,000 years, originally namely all our ancestors had brown eyes. The blue eyes seem to be caused by a mutation,... 

A basic characteristic of man is his eye color. Whether brown, blue or green – that is, among other things stated in the passport. But why do people actually have different eye colors? Iris and pupil The iris and the iris is the colored part of the eye and is almost an aperture for the eye to dark. controls the incidence of light: it narrows in brightness – the light is so low. The iris... 

Contact lenses, which are supposed to be fitted directly in the eye’s iris and pupil in contact with the cornea (cornea is the tissue who covers the outer visible surface of the eye), are preferred to be worn by some people to correct any vision defects. In other cases, like severe astigmatism or nearsightedness or could be cases following a cataract surgery, contact lenses are more effective, looks... 

Many people who grew up before contact lenses become popular or were widely prescribed are hesitant to make the switch from regular glasses. You may still have in mind the various forms of early contact lenses made of hard plastic, which many wearers found uncomfortable. Today, newer soft lenses and gas-permeable hard lenses, which allow oxygen to reach the cornea, are more easily tolerated, less... 

When I wore hard contact lenses, the optometrist told me to blink often and completely. With my new soft lenses he says I don’t have to blink so much. Why? -Your old hard lenses prevented essential oxygen from reaching the cornea; blinking solved the problem by circulating oxygen-filled tears under them. By contrast, soft lenses have a high water content which allows oxygen to dissolve in the lens... 

different eye colors Beautiful eyes are one of the most attractive features of a face, and their color plays an important part. Color in eyes comes from the iris, which less behind the cornea and in from of the lens. In the centre of the iris is the pupil, an opening that admits lights to the eye. The iris is made up of collagen, a tough fibrous protein found also in tendons and the body’s connective... 

deteriorated eyesight It’s unusual to see a middle-aged person holding a book arm’s length in order to read the print, or struggling for some time to thread a needle. Both are signs of presbyopia, difficulty in focusing the eyes on close objects. As we grow older, the lenses in our eyes lose their elasticity and ability to focus for near and distant vision. Most people notice this at about... 

Without much fanfare, corneal-transplant operations have restored clear sight to hundreds of thousands of people worldwide. The procedure, the most common form of organ transplant, is now routine, even at some small, country hospitals. Corneal transplants replace the cornea,  the eye’s protective window through which light passes to the lens and onto the retina. For good vision the cornea ... 

We recognize color because we have special receptors behind the retina at the back of the eye. Light enters the lens, passes  through the whole of the retina, and strikes these receptors, which are divided into rods and cones. Color perception depend mainly on the cones, which are of three kinds, each containing different color-sensitive pigments. One responds best to red (long wavelength) light,...