The quality of the eyeglasses chain stores is relatively stable and reliable.
As the eyewear chain enterprises spread across the whole city or across regions, they occupy a large share of the local market, and the resulting scale effect reduces their own procurement costs and greatly enhances the awareness of brand quality. Therefore, the procurement of eyewear products is critical. Those defective products are much less likely to appear in these chain optician stores, which naturally ensures that overall product quality improves.
What Are Bifocal Glasses?
Vision changes seem to be related to age. Presbyopia occurs in the middle age of one person, affecting your eye’s ability to focus. But it can be caused by bifocal glasses.
Bifocal glasses are divided into two parts to accommodate two different prescriptions in one lens. One area of the lens will have one prescription (usually distance) and a segment in the lower half will have the other (usually near vision).
Bifocal glasses were invented by Benjamin Franklin, who solved his own vision problem by taking the lens from his reading glasses and distance glasses and cutting them in half. Then remade the cut lenses into a single pair of bifocals and put the distance lens on top and the reading lens on the bottom.
However, the bifocal glasses come with some problems. So, in the following section, we will show you some common bifocal glasses problems.
Each pair of glasses has its own size.
People began to shop for myopia glasses online, but because of lack of experience, many times the size of glasses is not appropriate. At this time they used to complain about the business or glasses. It is really because that they do not see the size of the frame. Just like our clothes and shoes, each qualified frame has its own size. Usually, the size will be marked on the inside of the temple or the bridge of the nose. The manufacturer will clearly mark the width of the frame, the width of the bridge of the nose, and the arm length of the glasses.
How to Test Blue Light Glasses (Amber and Red Lenses)
This section will show you how to test blue light glasses with amber or red lenses.
1. The Black and Blue Squares Test
1. Prepare black and blue paper.
2. Wear your blue light glasses after sunset and check whether both paper appear black.
3. If they do not appear black, your blue light glasses can’t block all blue light.
2. RGB Color Chart Test
1. Prepare an RGB color chart as follows.
2. Wear your blue light block glasses and look at the chart.
3. After wearing blue light blocking glasses, if the B section becomes black and the G section becomes darken, it shows that your blue light glasses block blue light and some filter some green light.
4. The less bright the green circle with your blue light glasses, the better they are.
Besides the above ways, you can ask the professional optician to perform a professional blue light glasses test, which would be more reliable. After that, you can know whether your glasses work effectively to block blue light.
What’s more, if you want to purchase a pair of effective blue light blocking glasses, you can try Koalaeye Optical. It is cheap and provides free shipping services.
How about the optician center at Walmart?
Sixty-four percent of American adults wear prescription glasses, more than 157 million people. Since Walmart is the largest manufacturer of finished prescription glasses in the United States, the glasses are likely to come from Walmart. In reality, it's the only product they produce from start to finish. The ultimate goal of Walmart Glasses is to serve more customers faster and with better quality.
The optician center is not very big, but there are many kinds of glasses frames, and Walmart is the big backing, so the quality is relatively reliable. There are famous brands of lenses, a little more expensive, but certainly cheaper than the nearby optical stores. And you can pick and choose.
Which is better, Essilor lens or Zeiss lens?
1. Different high-density resin substrates. Essilor Diamond Crystal series 1.74 lenses use resin with a density of 1.46 as raw materials. The lens itself has higher hardness. Combined with Diamond Crystal series film layers, the lifespan of the lens is better improved. The outstanding abrasion resistance is obvious.
2. Different technical support. The greater the density of the lens, the harder the substrate. However, the larger the density of the lens under the same volume is heavier. Therefore, Zeiss has the best trade-off between density and component and selects high density on the basis of high refractive index and frivolity substrates.
3. Different Features. The anti-fog molecules on the two surfaces of the lens are activated by an anti-fog activator. Therefore, the fog differentiates into a thin layer that is invisible to the eyes, instead of forming a fog. Each spray of activator can last about a week. Zeiss resin lens guarantees up to 99.4% of the lens light transmittance, and the naked eye can no longer feel whether the lens is worn or not.
The Disadvantages of Trivex Lenses
In this section, we will show you the disadvantages of Trivex lenses.
- Trivex lenses have less availability, especially compared with polycarbonate lenses.
- Trivex lenses cannot provide the same degree of thinness as high-index lenses.
- Trivex lenses are expensive than regular lens materials.
