How to understand the glasses prescription?
The forms of the glasses prescription are in a great variety, but the basic items are the same such as name, sex, age, occupation and so on. The most important items are the nature of the sphere lens, the diopter, the refraction degree of the column lens, the axial position, uncorrected visual acuity of the right and left eyes, corrected visual acuity as well as the pupil distance.
Now I would like to tell you the meaning of the marks in the prescription.
OD / RE / R : right eye
OS / LE / L : left eye
+ : Convex lens ( for the hypermetropia )
- : Concave lens （for the myopia）
After “ +” or“ –” , the Arabic value is lens’ diopter, but what needs to pay attention to is that diopter in the prescription glasses and the strength of eyeglasses are not the same, a difference of 100 times between them, for instance, – 1.00D is equal to 100 degrees which we usually say;
DS : Spherical lens （both for hyperopia and myopia ）
DC : Cylindrical lens ( for astigmatism )
Behind DS, there is a mark “()”, representing the spherical lens “United” the following the cylindrical lens; at the back of DC, there is also a mark “×”, separating the front degree of astigmatism from the behind the astigmatic lens axis （1～180°）;
PD : pupil distance
For example,
Ｒ：—2.OO DS () — 2.OO DC × 90°
ＰＤ：63mm
It stands for right eye，200 degrees of myopia with 200 degrees of astigmatism, degree of astigmatism axis is 90 °, the pupil distance is 63 millimeters .
