Myopia and hypermetropia
To be well perceived, an image must be perfectly focused on the retina (and not before or behind the retina). Focusing power and eye length from the cornea to the retina must match. This is guaranteed by a complex system of control that develops during the growth of the eye. However, the length of each eye does not always correspond precisely with the focusing power of the cornea and the lens. When the length is too short a blurred image appears on the retina. In theory, the image would be perfectly focused on a point behind the retina: the hypemetropic patients see the objects better when they are farther away from them.
On the contrary, when the length of the eye is too long in relation to the focusing power, the image, again, is blurred. In this case, the image is clearly focused in front of the retina. Myopic patients see things better when they are closer.
When an eye has no refractive error, we say that it is emmetropic.
You should know that Bellevue clinics have all the latest technologies available to diagnose and monitor cases of myopia and hypermetropia.