How can I measure the frame size?
Use a ruler to measure the glasses you used to wear comfortably and record the width of the frame and the total width in front of the frame. And compared with the frame width of the selected frame and the total front width of the frame. Frame width size difference of one or two millimeters does not matter, and the total front width of four millimeters does not matter. You can use a ruler to measure the approximate distance between the temples. Usually, the width of the inner side of the frame is the same as the temple value or about 3MM larger than the temple value.
Titanium glasses are very popular.
Nowadays, the relatively popular titanium glasses, taken from titanium metal light, are not easy to break, are elastic, have super corrosion resistance, have a good touch, are non-allergic, and have memory characteristics. They have become a new type of glasses frame material. So that the wearer will no longer wear traditional overweight glasses, with no long-term pressure on the bridge of the nose caused by muscle oppression, and another discomfort. And they do not have to worry about glasses after long-term use of discoloration and lackluster and other problems. The titanium frame is more and more popular and becoming a fashion. Especially the high-end business elites praise pure titanium frame. No matter from the material, lens frame, suitable crowd, they can say to be an especially good choice!
How do myopic glasses work?
The formation principle of myopia is that when the light from the outside world enters the eyeball, it is refracted by the eyeball's refractive system and cannot be accurately imprinted on the retina. The image is in front of the retina. If a concave lens is placed in front of the eye before the light enters the eye, it shifts the focus of the myopic eye from a point in front of the retina to the back, so that it lands directly on the surface of the retina. When parallel light passes through a concave lens, it diverges, meaning that it has already diverged once before entering the eye and then is refracted normally by the eye's refractive system. When the light is refracted through the eyeball, the distance of the image will be longer. So the distance of the image will be correspondingly pushed back compared to the non-divergent light. But it will just fall on the retina, and the image will be accurate in the right place.
What Are Varifocal Glasses?
Varifocal glasses, also known as varifocals, varifocal lens, PLA, or progressive lenses, have a gradual change in strength from the top of the lens to the bottom with multiple focal points in between. Unlike bifocals, varifocal glasses have no specific area of lens strength, but progressive lens zones.
The way to look through varifocal glasses depends on what you want to look at. If you are looking at the distance, you look through the top of the lens. If you want to look at the close objects, you may need to move your eyes lower to keep the objects in focus. For the best close-up focus, you need to look through the bottom of the lens.
The benefits of varifocal glasses are that they do not need to buy or prepare 2 separate pairs of glasses or need to switch between frames for different vision needs.
However, if you wear the varifocal glasses for the first time, you may come across some problems.
Brick-and-mortar stores have fewer customers.
Brick-and-mortar stores are known to have a significantly smaller customer base, targeting a particular county or even a particular region and population. Mainly aimed at young students.For physical stores, their income range is relatively narrow. Therefore, in order to make more money, every physical store can only make a profit by raising the single sale price. Online stores attract consumer demand from all over the country and the world through the Internet.
What is blue light?
Our daily lives are inseparable from mobile phones, computers, tablet computers, and other electronic products. Many people's eyesight is also going downhill due to long-term exposure to strong light electronic screens, and their eyes are more or less potentially adversely affected. It is found that many optical stores sell blue light filter glasses, which have the function of blocking 99.9% UV and scattered blue light, alleviating visual fatigue. They claim that these glasses can block short-wave blue light emitted by electronic products such as mobile phones and computers, and even prevent age-related macular degeneration so they are much sought after by consumers. The price of these so-called anti-blue-light glasses varies greatly, ranging from dozens of dollars to several thousand dollars. Do these blue light blocking glasses really have so many magical functions?
The natural light seen by the human eye is composed of a spectrum of different colors, including red light, orange light, yellow light, green light, blue light, indigo light, purple light, which gives people a visual feeling of white. Different wavelengths present different colors visually, and the shorter the wavelength, the higher the energy. At present, products with electronic screens such as computers and mobile phones use LEDs and other materials to emit light mainly in three colors of red, green, and blue, and blue light accounts for the main part. Blue light belongs to the range of visible light, belongs to short waves. And the wavelength is between 400 nanometers and 500 nanometers, which is close to ultraviolet and carries a large amount of energy. And this part from 400 nanometers to 450 nanometers is called high-energy short-wave blue light.
The classification is different.
Acetate frames can be divided into two kinds, one of which is the lens using acetate fiber processing of plate cutting. The other is the injection frame. It uses acetate fiber particles. Acrylic acid is a kind of unsaturated organic acid, which can be derived from a series of compounds to form a large class of acrylic products. Acrylic acid downstream products contain common acrylate and special acrylate. It has the characteristics of heat resistance, weather resistance, aging resistance, strong adhesion, water resistance, acid and alkali resistance, stickiness resistance, and environmental friendliness.