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Anonymous users2024-02-11The lens label LR indicates the left eye and the right eye, and the prescription of the spectacle lens, respectively, and the latter indicates the degree of astigmatism.
Indicates that your vision is nearsighted.
Add astigmatism.
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Anonymous users2024-02-10Lenses refer to the refractive index of spectacle lenses. The higher the refractive index, the thinner the lens, and the difference in image quality. Therefore, when choosing lenses, it is necessary to choose according to the power in many aspects, not only considering the thickness of the lens, but also considering the image quality.
Lens refractive index.
Lenses are superscripted74 refers to the refractive index of the lens, for myopia.
For glasses, the higher the refractive index of the Lujin lens, the thinner the edge thickness of the lens, all other parameters being the same. The refractive index of a lens is the ratio of the propagation speed of light in a vacuum to the propagation speed of light in the lens material, which reflects the ability of the lens to refract light. Traces shouted.
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Anonymous users2024-02-09Summary. Hello, as far as I know. This refers to the right eye, and the equivalent spherical lens of the left eye refers to the refractive power of the lens, that is, the ability of the lens to change the divergence of the beam.
Spherical lens means that the refractive power of a spherical mirror is -1 meter.
A cylindrical surface is defined as having a refractive power in the direction of 163 degrees, with a focal length of -1 meter, and no refractive power in the direction perpendicular to it.
What does spherical equivalence mean?
Hello, I have seen your question and am looking for an answer for you, please don't worry, I am working on it.
Hello, as far as I know. This refers to the right eye, and the equivalent spherical lens of the left eye refers to the refractive power of the lens, that is, the ability of the lens to change the divergence of the beam. Spherical lens means that the refractive power of a spherical mirror is -1 meter.
A cylindrical surface is defined as having a refractive power in the direction of 163 degrees, with a focal length of -1 meter, and no refractive power in the direction perpendicular to it.
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Anonymous users2024-02-08Summary. Hello, glad for your question. 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.
What is the difference between lenses and lenses?
Hello, glad for your question. The lens belongs to the lens of medium folded dust Li Chun emissivity, both spherical design and aspherical design scrambling scheme, the lens is a high refractive index lens, only aspherical design. 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 emissivity.
Usually the lenses are marked with .74 refers to the refractive index of the lens, and the higher the refractive index, the thinner the thickness of the lens. The higher the refractive index, the thinner the lens, i.e., the lens has the same thickness at the center, the same power of the same material, and the edges of the lens with a higher refractive index are thinner than those with a lower refractive index.
Also, comparing the two refractive indexes, the hardness of the refractive index lens is higher, and the Abbe number is also higher. But these are not the deciding factors in the choice of lenses. Because you can't feel the difference between these two factors in general.
Note: Generally, it is best to choose glasses that are easy to bump into the lenses such as rimless or half-rim, because the hardness is high, and it is not easy to break. As for what others say or, now it means that there are very few optical stores to sell, and if there is one, you can choose it, but it is better not to choose if it is frameless.
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Anonymous users2024-02-07It represents the refractive index of the lens, and the higher the refractive index at the same power, the thinner the lens will be. Lenses can be selected according to the actual situation.
The refractive index of general glasses is: the highest refractive index of plastic lenses, and the refractive index of glass can be achieved;
The larger the digital deficit, the thinner the lens thickness at the same degree, the lower the Abbe coefficient, and the higher the dispersion coefficient.
Lens refractive index and Abbe numberThe Abbey number is used to express the inverse proportional index of the dispersion ability of transparent substances, the smaller the value, the more severe the dispersion phenomenon, that is, the rainbow edge phenomenon may appear when looking at the object, which brings the problem of clarity and color authenticity, and may also cause some people to adapt to the problem of longer adaptation, reduced wearing comfort and dizziness. Therefore, the minimum Abbe number of lenses for human wear should not be less than 30.
Generally speaking, the higher the refractive index of the material, the lower the Abbe number. However, with the upgrading of lens material technology, this rule is gradually being broken.
The above content reference: Encyclopedia - Refractive Index of Lenses.
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Anonymous users2024-02-06Refers to the refractive index of the lens, the higher the refractive index, the thinner the lens, but the corresponding dispersion is greater, and the refractive index is also high67 And, individual brands will have, with glasses the refractive index is not the higher the hidden hole, the better, a certain branch and to choose according to their own power, interpupillary distance and frame size;
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Anonymous users2024-02-051. The weight and thickness are different.
The lens is heavier than the lens. When other parameters are the same, the edge is thinner than the edge.
2. Abbe number.
and dispersion are different.
The Abbe number of the lens is lower than that of the lens, and the dispersion phenomenon occurs.
More serious than lenses. 3.**Different. The lens is lower, while the lens is higher.
3. **Different.
Refractive index lenses are produced more in China, so they are relatively low, while refractive index lenses are relatively few in China, so they need to be used from abroad, so they are relatively high.
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Anonymous users2024-02-041. The weight and thickness are different.
1. Refractive index: The refractive index lens is slightly heavier than the refractive index, but when the myopia degree is relatively low, there is little difference between the two.
2. Refractive index: Under the premise of the same other parameters, the higher the refractive index of the lens, the thinner the edge thickness of the refractive index lens, the lighter the lens, and the more beautiful and comfortable to wear.
Second, the Abbe number and dispersion are different.
1. Refractive index: the smaller the Abbe number value, the more severe the dispersion phenomenon, generally speaking, the higher the refractive index of the material, the lower the Abbe number, and the Abbe number of refractive index lenses is generally lower than that of refractive index lenses.
2. Refractive index: With the upgrading of lens material technology, the refractive index of refractive index lenses is higher than that of67, but the Abbe number is higher than that of refractive index lenses and most refractive index lenses.
Third, ** and the market is different.
1. Refractive index: refractive index lens** is low.
2. Refractive index: refractive index lenses are relatively high, in the past few years, there are very few manufacturers in the domestic market that independently develop and research high refractive index lenses, and high refractive index products are almost all imported, which is not only expensive, but also its quality and performance can not meet the requirements of consumers.
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Anonymous users2024-02-03First of all, the refractive index is an important parameter that distinguishes lenses. At present, the refractive index of the more mainstream lenses on the market is74 etc.
Generally, the refractive index above the refractive index is considered high. In fact, this is the same as the size S, M, L, XL, XXL parameters of buying clothes, it is mainly used as a reference basis. From skinny to fat, you can choose the right size for you according to your needs.
The same is true for the refractive index, the luminosity of the eye from high to low, also choose the appropriate refractive index according to your own situation. Secondly, the refractive index of the same power and the same material will determine the thickness, beauty and quality of the lens. Because the higher the refractive index, the lighter, thinner, more aesthetically pleasing and relatively higher the lens.
Generally speaking, the higher the refractive index of the material, the lower the Abbe number, and the 1653 Abbe number of refractive index lenses is generally lower than that of refractive index lenses. For a person with more than 300 degrees of myopia, it is completely unnecessary to choose a refractive index lens. Therefore, when choosing lenses, in addition to meeting the basic requirements for correcting vision, it is also necessary to maximize the aesthetics of wearing.
For people with different powers, the refractive index of suitable lenses is also different. It's best to choose according to your actual situation.
The answer has been made for you, please check it out in time.
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