Acetate is a kind of thermoplastic resin obtained by esterifying acetic acid to acetic anhydride under the action of a catalyst. Acetate is resistant to water, gasoline, mineral oil, and lipids, weak alkaline solutions, and acids, excellent weather resistance, not resistant to ethanol, strong acids, and strong alkaline solutions. During thermoforming, it is very necessary to dry the material before forming. Acetate was born in the early 20th century, and was successfully trial-produced and industrialized by the UK in the early 1920s. At present, it is the second-largest variety in cellulose fiber after viscose fiber. Acetate can be used to make textiles, cigarette filters, film bases, and plastic products.
Dark-rimmed glasses with wider frames
When choosing dark frames for round faces, one should pay attention to the width of the frames. If dark frames give people a feeling of narrowing, then the frames will appear smaller. Small frames make your face look bigger and rounder, so choose frames that are wide. If you can't wear a wide frame because the lenses are too strong, skip black and opt for something lighter.
Disadvantages of polarized sunglasses
Polarized sunglasses have many benefits. However, in some cases, non-polarized lenses are a safer choice. On cloudy days, drivers find that non-polarized sunglasses are better than polarized sunglasses due to the lack of glare and extreme sunlight.
Driving with polarized lenses after snowing can be dangerous for drivers. As the glare of polarized sunglasses is blocked, ice or snow on the road will not be visible. In this case, the advantages of polarized sunglasses will become the disadvantages that may cause accidents.
In addition, when driving along a dark road with few street lights at night, wearing polarized lenses will make it harder to see the road conditions because they dim the available light better than non-polarized glasses. Of course, in low-light conditions, it is best to avoid wearing sunglasses completely while driving.
The most significant disadvantage of polarized sunglasses is that they do not perform well on digital screens and displays. They can cause the images and information on the LCD screen to blur or disappear at certain angles. Don’t wear polarized sunglasses to use these devices while driving.
What Do Pinhole Glasses Do?
Pinhole glasses are often used by eye doctors who use them as a diagnostic tool to quickly check for vision impairments. Of course, pinhole glasses are sometimes used to treat nearsightedness or astigmatism. Pinhole glasses are also used in conjunction with an occluder, an instrument used to cover one of your eyes while you read an eye chart. The occluder is solid, while the pinhole glasses have a number of tiny pinholes. So, the doctor often uses it to check the potential of your vision.
Pinhole glasses are often used to check corneal distortion and cataracts. A cataract evaluation includes focusing light in the eye to check if vision capability behind the cataract makes it worth performing surgery.
How to adapt to progressive lenses?
People who are prone to motion sickness or have inner ear diseases may suffer dizziness, nausea, vomiting, and other symptoms due to their inability to tolerate the slight deformation of the visual objects, so they need to pay more attention when wearing them. For people who have not worn reading glasses before, it is not recommended to wear graded multi-focus glasses directly because their eyes will not be able to adapt quickly.
The principle of the anti-fog lens
Ordinary lens materials and water are wet, so water vapor is easy to fog up on the top. If this wetting relationship can be broken, the water vapor can be prevented from fogging up on the surface of the lens. The anti-fogging film is a kind of film which can prevent or avoid water mist agglutination effectively. It is divided into organic film and inorganic film. The inorganic film is mostly used for building, car window glass fogging prevention. For lens anti-fogging, the organic film is more used. The method is to wipe, spray (with an anti-fogging agent, and so on).
Rimless glasses provide the minimalist option for eyewear who want their glasses to blend in with their face, or want a larger field of vision. These aviator-shaped rimless glasses are very stylish, with the red or blue at the temple tip highlighting the colors. An adjustable nose pad provides a comfortable fit.