The difference between myopia and astigmatism

Abstract: the far vision after myopia can be corrected by concave lens. The degree of ametropia is usually measured by diopter. People with high myopia belong to the high-risk group of some eye diseases because of their long axis, such as retinal detachment.

myopia

and

are also called short-sighted eyes, because they can only see near and can’t see far clearly. When at rest, the parallel light from an infinite distance, refracted by the refractive system of the eye, gathers into focus in front of the retina, and forms an unclear image on the retina. The far vision after myopia can be corrected by concave lens. The degree of ametropia is usually measured by diopter. People with high myopia belong to the high-risk group of some eye diseases because of their long axis, such as retinal detachment.

astigmatism

the corneal surface of normal eyes has a spherical radian, just like the shape of basketball. After passing through it, the light is focused to a point, and you will see clear things. When the radian of the corneal surface is uneven, the light cannot focus on one point, and the things you see will become blurred and distorted. This common irregularity is “corneal astigmatism”, so what you see is blurred things.