4
2. Evaluate Astigmatism
Set the device to +6.00D
by rotating the dial.
Look through eyepiece, cover
the other eye by the occluder
and keep both eyes open.
Rotate the dial slowly until the end.
Observe the radial lines during this process.
A
B
Can you see some lines
are thicker than others?
If all lines are equally blurry or sharp like example A:
If you can see some thicker lines similar to example B:
no or little astigmatism, <1.00D;
astigmatism, ≥1.00D.
Repeat the process for the other eye.
3
1
2
4
EN
