How myopia is measured?

1.To find a regular ophthalmic hospital lens center to test the degree;

2.Test on computer. According to the visual acuity chart, you can test it yourself. The correct way to test the visual acuity chart is as follows:

Measuring myopia degree on computer
  1. About 1.5 meters away from the screen, parallel viewing.
  2. If the subject is wearing glasses or contact lenses, they can be tested directly without taking them off.
  3. The subjects covered their left eyes with their hands (without touching or pressing the eyes), while their eyes were open.
  4. The tester starts with a large figure and asks the subject to point out the direction of the opening of the figure. If correct, slowly test to the smallest figure.
  5. After the right eye test, the left eye was done in the same procedure.

After the test to see how much, and then look at the visual control chart, you can simply know their myopia degree

How myopia is measured?

3.Buy an eyesight chart and test it on the wall

1: A ruler;

2: A well lit environment;

3: A clear vision chart;

Test steps:

The visual acuity chart is placed on a horizontal plane which is flush with the eye and perpendicular to the line of sight;

The distance between the eye chart and the eye chart can be adjusted;

The vertical distance (CM) between the visual acuity chart and the pupil was recorded;

Measurement of myopia with visual acuity chart

Note: if monocular vision is tested, a medium gray small object should be used to cover the other eye;

If both eyes are used at the same time, the composite visual acuity of two eyes is tested, which is generally higher than that of monocular vision.

During the whole test process, the eyes should avoid direct light and ensure sufficient light on the photos; otherwise, the test results are inaccurate.

Do not let the object directly touch the pupil, pay attention to protect the eyes!!!

Visual acuity calculation:

Uncorrected degree = – 10000 / distance

For example, the distance measured is 40.0cm

Then the degree = – 10000 / 40.0

=- 250 (degrees)

The visual acuity of the eye was 250 degrees.

In addition, if there is astigmatism at the same time, the measured degree will not be accurate,

This method gives a comprehensive degree, which will be higher than the simple myopia degree. if necessary

Glasses should be tested by professional institutions.

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