Lasik in Istanbul - The Eye

 

General Info

The eye is one of the most important organs of the intelligent human being. The features of this incredible organ are amazing. Approximately 80% of perception in human beings is through the eyes. 70% of sensory receptors of the body are in the retina layer of the eye. Sony's 2002 model most advanced digital camera has 4,200,000 receptors while the human eye operates with an incredible sensitivity provided by its 120,000,000 black & white and 6,500,000 color receptors.

How do we see?

The eye functions like a camera or more like a video camera. Light rays coming from the objects arrive on the cornea first. The cornea provides 70% of the refractive power of the eye. After refracting the light rays, it directs them to the lens through an aperture called the pupil. The lens bends, in turn, refracts the rays again. It makes a fine adjustment to focus the light rays on the retina. This adjustment is similar to the auto-focus function of cameras. This superb, silent and continuous auto-focus function is due to the lens' ability to change its refractive power by altering its form and thickness. This function is called accommodation. In a non-accommodating young eye the refractive power of the lens is below 20 diopters but with maximum accommodation it increases to more than 30 diopters, which is nearly equal to an 8.5 diopters increase in the eye's total refractive power. Because of this ability the young eye can see both near and far objects well.

 

  - Lasik

  - The Practice

  - The Team

  - The Procedure

  - The Process

  - The Candidate

  - The Eye

  - The Trip

  - The Cost

  - The City Istanbul

  - Contact Us

 


Discover Travel

Turkey

2005


After the light rays are bent at the lens, they pass through the vitreous, the jelly-like substance filling the back part of the eyeball, and reach the retina. The retina, which makes up the inner lining of the eyeball functions like a camera film, or a CCD of a digital video camera. Then light rays are converted into electrical impulses by the retina and carried to the brain by the optic nerve. These impulses are processed and perceived as images by the brain.

REFRACTIVE ERRORS

An eye that , which does not have any refractive errors, and has the ability to see the far and near and distant objects clearly, is called an emmetropic (normal) eye. A refractive error means that the shape of your eye does not bend (refract) the light rayscorrectly. In other words, the eye can not focus images properly, resulting in a blurred image. In an emmetropic eye parallel rays of light from a distant object and divergent rays of light from a near object focus on the retina after being refracted by the cornea and the lens. The eyes, having refractive errors have problems with focusing light rays on the retina. Myopia (nearsightedness), hyperopia (farsightedness), astigmatism and presbyopia are names given to different refractive errors.

The refractive errors are quantified with the power of the lens that corrects the refractive error. The unit of the lens power is measured in diopters. 1 Diopter (D) is equal to the optical power of the lens which has a focusing distance of 1 meter. A lens with 1 diopter power focuses parallel light rays at 1 meter while a lens with 2 diopters power focuses parallel light rays at 0.5 (1/2) meter.
Total focusing power of the eye is between 58 and 71 diopters. Due to this amazing focusing ability the eye can see images from 25 cm to infinity by focusing on a tiny screen (retina), which is only 17 mm away from its lens.


About Us  Corporate  Incentives  Golf  Trade  Tours  Istanbul CityTours   I  Restaurants  I

City Breaks Istanbul  Subscription Hotels Accommodation Packages Transfers  I 

Photo Gallery  Contact  I  Excimer Laser  I  Lasik in Istanbul  I  Cosmetic Dentistry  I  Motorsports 

Moto GP Istanbul  I   F1 Packages  I  Soccer Training Camps  I  Football Camps  I   Euroleague  I

 

Discoer Travel Turkey - 2005