Glasses prescription?

Question

I recently got my eyes tested and my cylinder values are the same (-0.75) but on the Axis reading it appears as follows:

Right eye: 5.0

Left eye: 170.0

I am just curious to know which reading is closest to healthy sight? The 5 or the 170 ie: which eye is most faulty?

Answer 1

Well here is a fun way to find out

take a piece of paper and cut a hole in in (small)

sit on one end of the room

put the paper in front of you (arm lenght)

with both eyes open make an object be seen in the hole.

close your left eye

can you see it

if not, your left eye is weak

open your left eye

close your right eye

can you see it

if not, your right eye is weak

Answer 2

Actually, in terms of magnitude of visual defect, both eyes are about the same, having a mild degree of astigmatism. Let me describe it further. If you had a clear, round bowl of flexible plastic, this would be like a "normal" cornea. If you squeeze the sides of the bowl so the opening looks like an oval it would be shaped like a cornea with astigmatism. In the eye the "oval shape can be oriented in any direction. By using a cylindrical lens, of the proper strength, rotated 90 degrees off from the defect it compensates for the problem. So the 5.0 and 170.0 numbers refer to the orientation of the cylindrical lens to best correct for the problem in each eye.

Answer 3

the axis has nothing to do with the eyesight. -.75 cylinder is not bad, you just have slight astigmatism. the axis is determined by where the cylinder has to fall on your line of vision in order to get "20/20"

confusing, i know. but the cylinder is part of your astigmatism, not the axis