My OD Sphere is -0.75 ; Cylinder-0.50;Axis is 140;Dist PD 31.5 and Near PD 29. What does this mean?

Question

My OD Sphere is -0.75 ; Cylinder-0.50;Axis is 140;Dist PD 31.5 and Near PD 29. What does this mean?

Answer 1

What do you mean, what does this mean...

It is just a mild correction because you are nearsighted, and have a bit of astigmatism..

The PD measurments are just the distance between your pupils, for placing the optical centers of the lenses.

You have just one eye ?

Answer 2

this is the prescription for your right eye

you have what is known as an astigmatism, which means your eye has different focal points in different planes. the sphere and cylinder power correct these.

the axis is in which these powers are to be placed.

the distance pd (Pupillary Distance) is the distnace between your two pupils - as this is only your prescription for your right eye this will be your monocular pupillary distance, this is the distance between the centre of you bridge on your nose and the centre of you right and leftpupil when you are looking at a distance object. the near pd is the distance between the centre of your bridge on your nose and the centre of your right and left pupil when you are looking at a near object. however this is all for your right eye. although its very likely that both your right and left pd's (near and far) are identical. pds are always measured in mm.

when testings eyes we measure in diopters, these can be postive or negative. these are the sphere and cylinder measurements in your prescription. Someone with perfect vision will have 0. we measure going up and down in 0.25's so your prescription is very little. generally a prescription with negative numbers means that you require a correction for distance, and a prescription with positice numbers means that you require a correction for near (Reading)

hope that helps!