How much does it cost to get glasses at Walmart?
The price of the frame varies according to the material. Also, the price of the lenses will vary depending on your prescription. Walmart Vision Center provides frames online starting at less than $20 and going as high as $165. More than 250 prescription glasses are available for under $100, including styles for men, women, and children. The price of the lens depends on the type and frame you choose. The fundamental price of the frame includes clear, plastic, single-vision lenses with scratch-resistant coatings.
What is the progressive multifocal lens?
The lens of progressive multifocal glasses can change the refraction of the lens at the upper part of the central channel of the line of sight, which can effectively solve the difference of refraction when people view objects at different distances from long, medium, and short distances. Depending on demand, people have the flexibility to change or compensate vision according to visual distance, making it easier to help to adjust your vision in a variety of situations.
How are we nearsighted?
The light from external objects to the eye needs to be refracted by the lens before it can be imaged on the retina. The refractive power of the lens depends on the contraction and relaxation of the ciliary muscle. When we look at close objects, the ciliary muscles contract and the lens becomes thicker. When we look at distant objects, the ciliary muscles relax and the lens becomes thinner. Adjust the focal length of near and far objects so that they will show a clear image on the retina. If you use your eyes too often and the longer the ciliary muscles work continuously, the ciliary muscles will spasm because of too much tension. At this time, the lens cannot be adjusted and thinned. After the light from a distant object is refracted by the lens, the imaging position will fall in front of the retina instead of on the retina. Only a blurred image can be seen, which becomes myopia.
There is another situation. For some people, due to genetic factors, in the process of growth and development, the front and rear wheelbase of the eyeball will gradually become longer. In this way, although the adjustment function of the ciliary muscle and the lens is normal, the image formed will also fall in front of the retina due to the longer the axis distance of the eyeball, which can also cause myopia.
The two causes of myopia are different. Myopia caused by ciliary muscle spasm is called 'pseudo-myopia'. As long as the ciliary muscles are relaxed, myopia can be reversed. Myopia caused by the extension of the wheelbase of the front and back of the eyeball is called 'true myopia', which cannot be reversed and can only be corrected by myopia glasses.
What are the benefits of Silhouette?
The wonderful style suits both men and women. The glasses are made of strong, reliable, and not heavy metal. They adopt a screw-free design and high-quality process. The glasses are made of titanium alloy temples and are highly ergonomic. They are not heavy and elastic (only 1.8 grams in weight), independent of momentum changes and extreme gravity. The temples and nose pads are made of hypoallergenic titanium alloy. With no screws and hinges, they provide optimal safety in space conditions.
Are carbon fiber glasses better or titanium?
In terms of weight, the titanium frame is very light. The specific gravity of the pure titanium frame is about 4.5g/cm3, and the specific gravity of the titanium alloy frame is about 8.9g/cm3. The pure titanium frame is lighter than the titanium alloy frame. However, carbon fiber glasses are lighter in weight. The carbon fiber glasses launched by LOHO are only 7.87g, which is very light to wear.
In terms of hardness, titanium has a high hardness, about twice that of stainless steel, twice that of iron, and six times that of aluminum. Carbon fiber is lighter than aluminum, harder than steel, and its strength is ten times that of iron.
In other respects, the titanium frame has the advantages of corrosion resistance, acid and alkali resistance, high stability, good elasticity, good toughness, and resistance to deformation. The carbon fiber frame has the advantages of corrosion resistance, high temperature resistance, radiation resistance, good elasticity, good flexibility, and abrasion resistance.
It can be seen from the above comparison that carbon fiber glasses have the general advantages of titanium frames. In terms of weight, carbon fiber glasses are much lighter than ordinary pure titanium glasses.
How to choose blue light blocking glasses?
Nowadays, electronic products such as mobile phones and computers have become indispensable tools in our lives. While these high-tech products bring us convenience and fun, they also bring symptoms such as eye fatigue and myopia. Subsequently, blue light blocking glasses have also received everyone's attention. Anti-blue glasses are only suitable for people who use electronic products for a long time, not for people who are visually fatigued. Exposure to such unnaturally strong blue light for a long time every day, especially for teenagers and children, needs to pay more attention to the prevention of blue light. So, how to choose suitable blue light blocking glasses for kids?
Anti-blue light is necessary, but not all blue light can be filtered out, because blue light will interfere with the body's melatonin secretion after being over-filtered, thereby affecting sleep. Therefore, when choosing blue light blocking glasses, you should choose appropriately according to your own eyes.
For how to choose anti-blue glasses, consumers can distinguish from the color of the lenses. Generally speaking, a lens with a yellow color will have the effect of blocking blue light. But too dark lenses will affect the contrast sensitivity. Therefore, it is recommended that consumers choose moderately. In addition, consumers should also pay attention to whether the glasses products (lenses, frames) have conformity marks, etc. It is best to choose professional and well-known glasses shops to match glasses.
What is a progressive lens?
A progressive lens is a lens whose upper sides are used to see far, and the lower side is used to see near. The distance from the fixed distance power above the lens to the near power fixed below the lens does not change suddenly, but a gradual transition between the two through the gradual change in refractive power.
Standard progressive lenses are multifocal lenses with three observation areas, farsightedness, intermediate vision, and nearsightedness. Unlike bifocals, there are no visible lines between each viewing area. They have a seamless, invisible design, where the optical power changes 'gradually' throughout the lens. Many people confuse 'bifocal' or 'trifocal' with 'progressive' but remember that bifocals and trifocals have visible lines in the lens, while progressive lenses do not. Because progressive lenses have no lines in the lens, they are more popular multifocal lenses than bifocal lenses. However, is progressive lens good for eyes?
