1, you must have an optometry first, and then wear reading glasses after going to the Hypervision Stereo Center for testing.
2, left and right vision, pupillary distance, different degrees of myopia, hyperopia, astigmatism, etc. , ametropia to test.
3. If you like to play mobile phones or outdoor activities, you can choose lenses that prevent blue light and ultraviolet rays.
4. After wearing reading glasses, you can see the smallest words in the newspaper at 30 cm, and there are no symptoms such as object deformation and dizziness, indicating that reading glasses are suitable. If you are used to reading at a distance of 40CM, you should lower your diopter slightly, and vice versa. If you are in poor health, you can consider increasing the degree appropriately.
5. Wearing reading glasses requires an adaptation period and regular maintenance.
6. Generally, the difference between reading glasses of both eyes cannot exceed 400 degrees.
7. If there are diseases that affect the eyes, such as three highs, drug abuse, etc. Don't rush to get glasses, consult a doctor first and then prepare glasses according to the doctor's advice.
8. For comfort, choose one-to-one customization. Match glasses according to your age, occupation, hobbies, face shape, vision and other data.
First, how to choose the right lens, first clear your own situation.
Degree of optometry: after accurate vision, get the data such as the degree of glasses needed to correct vision, and then judge and choose lenses according to the optometry data;
Life needs: Choose appropriate glasses according to life needs such as work, study and entertainment. The types of lenses selected for different purposes will be different. For example, you like watching TV, playing computer, playing mobile phone, reading books, traveling outdoors and driving.
Usage environment: the environment in which glasses are usually used, such as whether they work in high temperature, cold storage, chemistry, pharmaceutical experiments, welding and other environments. These problems should be considered.
Second, the lens elements that need to be mastered with glasses
For lenses, it can be divided into three categories: material, surface type and film layer.
Material: Abbe number, specific gravity, refractive index, ultraviolet protection, impact resistance, etc. Among them, "Abbe number" is the most important when choosing lenses, and it is an index of lens clarity. The higher the Abbe number, the clearer it is. The higher the natural Abbe number, the higher the price.
Refractive index: the refractive index is related to the thickness of the lens. The higher the lens, the thinner and more beautiful the lens, and the better the hardness of the lens.
Surface types: spherical, aspheric and double aspheric. It can affect the authenticity of lens imaging, with large spherical aberration, small aspherical aberration and even smaller double aspherical aberration. Aspheric and double aspheric surfaces are the mainstream in this field now, and it is easier to adapt to them when they are first worn.
Film layer: coating can increase the light transmittance and make the lens more beautiful. It can also improve the hardness and make the lens more wear-resistant. Water and oil resistance, more conducive to cleaning.
In addition, there are hardness, shape, strength, thickness, color, weight and so on. You should consider it when you wear glasses. If the use environment is special, you should also choose glasses with special functions, such as anti-ultraviolet, anti-electromagnetic radiation, anti-infrared, anti-high temperature, anti-oil, anti-acid and alkali, anti-dispersion, anti-deformation (ultra-thin aspherical lens), anti-glare and other functions. Such as welding lens, computer lens, underwater lens and fishing lens are all different.
Third, the comparison between resin lens and glass lens
At present, resin lenses are mostly used in the market, because resin lenses have many advantages over glass lenses:
1, surface gloss, smoothness, low refractive index, and thick resin lens with the same degree. The transmittance is higher than that of ordinary glass lenses.
2, low surface reflection, not dazzling.
3, the optical performance is extremely stable, easy to dye, and the texture is light.
4. Strong impact resistance. When the impact is broken, there are few fragments, and the fragments are large and dull. Minimize eye and facial injuries.
5. Good fog resistance, and a wide range of chemicals and chemical solvents.
6, it is not easy to produce bending and torsional deformation.
Lenses are disposable products and cannot be modified once they are manufactured. In order to avoid preventable losses, we should carefully consider the correct choice when setting.
Frame, now generally use titanium alloy. I think there are few plates on the market.