Note: The above tests are only preliminary assessments, and it is difficult to detect astigmatism in high myopia and hyperopia.
If you want to have a more comprehensive understanding of the parameters of the eyes, it is recommended to go to a formal institution or optical store for scientific optometry!
A friend asked me how to judge the astigmatism axis?
In fact, in addition to going to the optical store, we can also simply judge by astigmatism discs!
First, identify the direction of the sharpest line on the astigmatism disc. Because of people with astigmatism, lines in certain directions will appear solid, while in other directions they will appear dashed.
With this simple observation, you can calculate the approximate axis of astigmatism!
For example, if the line in the direction of 6 o'clock is the thickest and most solid, it is 6*30=180, and the axis position is 180. Remember, 12 o'clock is the same as 6 o'clock!
Isn't it simple?
In the same way, if the line at 1 or 2 points is the clearest, the axis is generally between 30 and 60.
At the time of optometry, the optometrist will judge your approximate astigmatism axis position by your feedback on which line is clearer and more solid.
Please note that astigmatism discs are only used for rough judgment, and the results cannot be used directly for glasses, and there may be some errors.
The optometrist only uses the astigmatism disc to make a rough judgment when refraction, and then uses a more accurate honeycomb map, and then passes through the crossed cylindrical lens (which is more accurate to the specific astigmatism axis and power) for further refraction!
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