How to check astigmatism

summary

Now more and more people are checked out, because often play electronic products lead to eye fatigue, so many people have the phenomenon of vision decline, that is, the phenomenon of myopia, and many nearsighted people have astigmatism phenomenon, share with you how to check astigmatism this common problem!

How to check astigmatism

First, the cylindrical mirror method: the cylindrical mirror with the same symbol as the spherical mirror is usually used, that is, the concave spherical mirror is also used for the cylindrical mirror. First, add a 0.5d cylindrical mirror and a spherical mirror at the same time, and slowly rotate the cylindrical mirror 180 ° for several times. When rotating the cylindrical mirror, ask the patient to pay attention to whether the clarity of the smaller characters on the visual chart has changed (regardless of the size, distance, etc.).

Second: if the cylindrical mirror is rotated repeatedly, the astigmatism will be said to change the definition, sometimes clear, sometimes fuzzy. When the vision is clearest, the axis of the cylindrical mirror is the axis of astigmatism. If the astigmatism axis is right, the astigmatism degree can be further determined.

Third: astigmatism meter optometry: it is an effective method to check the astigmatism axis with astigmatism meter. The commonly used astigmatism table is shown in Figure 2. When using it, cover one eye and let the examinee look at the astigmatism table in front. If the black lines on the astigmatism table are consistent, it means that there is no astigmatism or only a little astigmatism (about 0.25d-0.5d); if the black lines are inconsistent, it indicates astigmatism.

matters needing attention

Astigmatism people see things very blurred, for patients, in peacetime because it is not very clear whether they have astigmatism, so many times still need to pass the above test method to detect whether they have astigmatism, so as to be more sure.