In order to see, the eyes need light. A ray of light can get reflected, deflected, absorbed or bent, depending on the varied substances that it encounters on its course. When light passes from one medium to the opposite, like through water or a lens, it gets refracted. Certain structures within the eye have refractive properties that are almost like the lenses of water and have the power to bend the rays of sunshine onto a definite point of focus which is critical for sharp vision. Refraction happens when the light rays travel through the clear, curved front surface of the eye. The lens that is naturally present within the eye also helps in bending the light. Even the tear film present within the eye has refractive abilities.
Bapaye Eye Hospital, Nashik, a renowned name in Eye related problems, is a specialist eye hospital in Nashik when it comes to Refractive Eye Surgery.
Mechanism Behind Vision
It begins when rays of light that reflect off the objects meet up with the optical system of the eye and are then refracted, eventually focused into a sharp focus. For normal vision, this focus point should be on the retina. The retina is that part of the eye that covers the rear of the eye. The photoreceptor cells that are light-sensitive and capture images (more or less sort of a camera captures images) when it is exposed to light. These images are then transferred through the nerve optics of the eye to the brain where they’re interpreted.
In the same way as a camera’s aperture is adjusted to modify the amount of light that is required to expose a film adequately, the pupil of the eye narrows or widens to regulate the quantity of light that reaches the retina. When it’s dark, the pupil widens and when the light is extremely bright, the pupil narrows.
What are refractive errors?
Refractive errors are essentially a kind of vision problem that makes it difficult for someone to see clearly. They are the most common kind of vision problems. They are easy to detect and can be treated with the help of prescription eyeglasses, contact lenses or surgery.
Refractive errors are broadly of 4 main types:
- Myopia or near-sightedness which makes objects that are far appear blurry.
- Hyperopia or farsightedness which makes closer objects appear blurry.
- Astigmatism which makes nearby and faraway objects appear distorted and blurry.
- Presbyopia which makes it difficult for older adults to read and see objects up close.
The common symptoms of refractive errors include blurry vision, visual defect, hazy vision, eye strain, headaches, squinting, difficulty while working on the computer or while reading, seeing glare around bright lights.
Causes of refractive errors
The ability of the eye to focus the rays of light effectively and sharply on the retina depends totally on 3 factors:
- Eye length: If the eye is simply too short, the light is not ready to refract or focus by the time it reaches the retina. This results in farsightedness or hyperopia. If the eye is too long, the light gets refracted before it reaches the retina, resulting in myopia or near-sightedness.
- The curvature of the cornea: If the cornea is irregularly shaped and is not perfectly spherical, the light gets focused or refracted irregularly resulting in astigmatism. One may have myopia or hyperopia with or without astigmatism.
- The curvature of the lens: If the lens of the eye is curved too steeply compared to the curvature of the cornea or the eye, it causes near-sightedness. If the lens is just too flat and lacks curvature, it leads to farsightedness.
Bapaye Eye Hospital, Nashik, deals with all these eye problems in a specialized and trusted manner. If you are suffering from refractive errors, do not hesitate to visit a qualified ophthalmologist for Refractive Error Correction in Nashik.