I got this prescription at an eye-checking machine. I feel like my left eye is really bad and doesn’t see well in the distance. What do the results mean exactly?
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[Prescription](https://i.imgur.com/f7Vr7l5.jpg)
In: 6
On a simple lense, each face is cut as the surface of a sphere. With “0” spherical correction, the curvature of the inner face and the curvature of the outer face are equal; the lens is the same thickness throughout. It’s window glass.
With farsighted (+sph values) the inner face is cut to a larger sphere than the outer face. The middle of the lens will be thicker than the edge of the lens.
With nearsightedness, (-sph values), the inner face is cut to a smaller sphere than the outer face. The lens is thin in the middle, and thick on the edges.
SPH refers to the spherical correction the lens is to provide.
Next, CYL and Axis
A lens need not be spherical. It could have a greater curve in one direction than another. The lenses could be cut so that instead of the faces each being the surface of a sphere, they are instead the surface of an ellipsoid. Something like a football.
A “cyl” correction means the lens has a different curve in one direction than the other; it is “squished”. The “axis” direction tells you the orientation of the “squish”: a 0 correction would be a football held upright; a 90 correction would be for a football horizontal, laying on the ground.
This machine conducted 4 tests on each eye, and reported all 8 tests.
Finally, PD is “pupillary distance” – they need to grind the lenses so that when they are fixed to the frames, each one will be centered over your eye.
Your prescription is for a very minor spherical correction in each eye to fix nearsightedness, and a very minor cylinder correction in each eye to fix astigmatism.
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