How do you look at the power of your spectacle lenses, and how can you know the power of your specta

You can't accurately judge the power of the spectacle lenses by yourself, but you can preliminarily judge the power by looking at the thickness of the glasses.

The power of spectacle lenses is generally not visible, and when you want to wear glasses, there will be an instrument to check the power.

The prescription of spectacle lenses is generally measured by a professional machine, and if you look at them with the naked eye, the thickness of the spectacle lenses is directly proportional to the prescription.

If you match the power of your lenses well, you will not be able to see them with your own eyes in the future, so you can only go to the optical store and he will help you measure them.

Looking at the power of your lenses, it is actually difficult for you to distinguish the power of your lenses, so you have to measure them.

The prescription of spectacle is measured with a power meter. Usually the letter R stands for the right eye, the letter L stands for the left eye, and the letter DS stands for spherical lens. Also included is the difference between farsightedness and myopia.

For example, the minus sign represents myopia, and the plus sign represents farsightedness. In the case of DC, it indicates astigmatism, and between 0 and 180 degrees, it indicates axial. The specific prescription of the glasses must be measured with an instrument.

In general, the right eye is R, the left eye is L, the lens is DS, and there is myopia and farsightedness. The negative sign is myopia, and the positive sign is farsightedness. Astigmatism is DC with a certain axial direction behind it, between 0-180 degrees.

Therefore, if you want to know the specific results of the prescription of the original glasses, it is best to measure it with an instrument. If you need to change your glasses again, you generally need to re-re-opt, and then according to the results of comprehensive refraction, the final prescription of glasses will be obtained.

Refractive power: When light is emitted from one object into another substance with different optical densities, the direction of propagation of light is deflected. This phenomenon is called refractive phenomenon, and the unit that indicates the magnitude of this refractive phenomenon is diopter, which is usually expressed as "d".

The refractive power of the eye is generally measured by methods such as radiometry, computerized refraction, and comprehensive refraction.

In general, for the eye, the most direct refractive change is reflected in the curvature of the lens.

The lens is the most direct adjustment structure for people to see far and near, which is equivalent to a convex lens. Different from the physical convex lens, it is adjustable, that is, it can adjust its bending degree according to your own needs, so as to change the distance of the focus to achieve the purpose of seeing the object clearly.

If you want to measure the power of the lenses, you can go to your local optical store or the hospital's optometry center and measure the power of the lenses with a special instrument focimeter.

There is also a very simple "close-up" test to measure the power of the lens. Stretch out your finger and test it at 18 cm in front of your eyes, if your eyes look natural, and then look at the distance, if it is also natural, it means that the glasses are accurate. Otherwise, it is not allowed.

This 18 cm is for people under 25 years of age, and this distance varies depending on age. It is 20 to 22 cm around 30 years old, 22 to 25 cm around 35 years old, 25 to 28 cm around 40 years old, and 28 to 30 cm over 45 years old.

The steps to check the prescription of glasses are as follows:Tools: Lenovo computer, glasses prescription calculation table. 1. First of all, establish a "glasses power calculation table" in **.

2. Then enter the corresponding value in the cell.

3. According to the degree coefficient of myopia = (0-spherical value), we enter "=(0-f3)g3" in the "myopia degree" cell.

4. Click enter, and we will get the prescription of the glasses.

I can't see the prescription of the glasses, and the doctor told me when the prescription of the glasses is matched.

If you want to know the power of your eyes, you can do a simple test at home before having a professional eye eye examination, and you can go to a nearby pharmacy to buy an eye chart.

Hang on the wall, stand one meter away from the eye chart, blindfold one eye, and use the other eye to identify the smallest line on the eye chart with one eye, and the corresponding vision record value is myopia.

, change the eye and test it again.

After a simple test at home, you should still have a professional check-up in the same way as you are doing your health. You can choose to go to the eyeglasses store for a check-up, and the optician will have a professionally trained clerk who will let you sit in front of the electronic device, check you, and then determine the prescription of the eyes and recommend whether it is suitable for glasses.

If you are still not sure about checking your eyes in an optician, you can go to an eye hospital for a more professional examination, where a professional ophthalmologist will conduct professional tests and examinations for you, and there will be an eye power meter and other instruments in the hospital to check your glasses.

1. These numbers represent the optical refractive index of the lens, that is, in the case of the same thickness of the lens center, the lens with the same power and the same material, the edge of the lens with a higher refractive index is thinner than that of the lens with a low refractive index; The higher the number, the thinner the lenses, and the higher the **.

2. If the patient's prescription is less than four, only the lenses need to be selected when wearing glasses. But if the power is more than four, it means that consumers must choose lenses to see more clearly.

3. What is the difference between lenses and lenses? Lenses belong to medium refractive index lenses, which have both spherical and aspherical designs, and lenses are lenses with a high refractive index, and only aspherical designs. Aspherical lenses can reduce the edge phase contrast of the lenses, resulting in a clearer and more natural field of vision.

For the myopia group with a high general power, it is more suitable to choose aspherical lenses with high refractive index.

The glasses list looks like this:

The left eye and the right eye are examined separately, and the data will naturally be different.

In the form, r (right) means the right eye and l (left) means left eye.

Other words. Data in column r: Represents the data in your right eye.

Data in column l: Represents the data of your left eye.

The data is usually measured 3-4 times.

The line with * is the average of the previous refractions.

The line next to the number of references refers to the composite reference value.

The three key data must be clearly understood.

These three big data are the indicators that need to be measured when measuring vision, which are used to describe the visual acuity:

① s(spherical)

Spherical lens, refers to myopia and farsightedness.

c(cylindrical)

Cylindrical mirror, which refers to the degree of astigmatism.

a(axis)

Axis position, which refers to the direction of astigmatism.

Don't ignore the +, symbol in front of the number.

"Stands for farsightedness," - stands for myopia.

Because astigmatism is also divided into farsightedness and myopia.

Therefore, the astigmatism should also be marked before the symbol.

VD refers to the interpupillary distance (representing the test distance), about 12-13mm PD refers to the interpupillary distance, which indicates the distance between the two eyes from the center of the pupil.

After understanding the meaning of the characters, can you now read the optometry?

Take the following optometry sheet as an example:

Conclusions can be drawn from the optometry.

The right eye is myopic 100 degrees, combined with myopia astigmatism 100 degrees, and the astigmatism axis is 63 degrees;

The left eye is myopic 125 degrees, combined with myopia astigmatism 50 degrees, and the astigmatism axis is 96 degrees.

It is generally written clearly that binocular power astigmatism.

Summary. Hello teacher, it is a pleasure to serve you. A vision list is a result of computerized refraction.

In general, the English letter r stands for the right eye and l stands for the left eye. The s in the first row represents the spherical diameter, that is, the degree of myopia and hyperopia, and if it is a positive value, it means that it is a convex lens, that is, the degree of hyperopia; A negative value represents a concave lens, which is also a degree of myopia. The further right row is C, which represents the degree of astigmatism, that is, the power of the cylindrical mirror, the positive power represents farsighted astigmatism, and the negative power represents myopic astigmatism.

The next row to the right is the axis position, which represents the direction of astigmatism, such as 90 degrees or 180 degrees of astigmatism, and this 90 degrees is the axis of astigmatism. After that, the right row is corrected vision, such as or, i.e. vision with the corresponding prescription lenses. There is also an English letter PD below the row to the right, such as PD=60mm, indicating that the interpupillary distance is 60mm, that is, the distance between the pupils of the two eyes is 60mm, and the interpupillary distance is also very important when wearing glasses.

How to look at the prescription of the glasses list.

Hello teacher, it is a pleasure to serve you. A vision list is a result of computerized refraction. In general, the English letter r stands for the right eye and l stands for the left eye.

The s in the first row represents the spherical diameter, that is, the degree of myopia and hyperopia, and if it is a positive value, it means that it is a convex lens, that is, the degree of hyperopia; A negative value represents a concave lens, which is also a degree of myopia. The further right row is C, which represents the degree of astigmatism, that is, the power of the cylindrical mirror, the positive power represents farsighted astigmatism, and the negative power represents myopic astigmatism. The next row to the right is the axis position, which represents the direction of astigmatism, such as 90 degrees or 180 degrees of astigmatism, and this 90 degrees is the axis of astigmatism.

After that, the right row is corrected vision, such as or, i.e. vision with the corresponding prescription lenses. There is also an English letter PD below the row to the right, such as PD=60mm, indicating that the interpupillary distance is 60mm, that is, the distance between the pupils of the two eyes is 60mm, and the interpupillary distance is also very important when wearing glasses.

You are 350 degrees myopic in your left eye. The right eye is 325 degrees of myopia.