What are the characteristics of a titanium frame?
The so-called pure titanium, titanium refers to the purity of more than 99% of the titanium metal materials. To tell if a pair of glasses frame is pure titanium, we look at its purity. Because of the high melting point of titanium, lightweight, strong corrosion-resistance, used for the frame, they can wear for a long time, and will not let the bridge of the nose have a sense of pressure. But its disadvantage is that the material is soft, and only the relatively rough frame lines are made to ensure the stability and strength of the frame. Titanium frame has the advantages of corrosion resistance, acid and alkali resistance, high stability, good elasticity, good toughness, not easy to deform and fade. General glasses frame contains copper, so when we wear for a long time .it will produce verdigris, namely, copper sulfate. It is a toxic substance and is harmful to the human body. Because pure titanium tends to be soft, copper has to be added to make the frames more stable, which is why the frames have to be replaced over time.
How to buy contact lenses online?
Choose well-known brands.Nowadays, the contact lens brands in the market are mixed, with the proliferation of inferior products, but there are still some authoritative and well-known ones, like Johnson & Johnson, Bausch & Lomb, which are products recognized by most users, and you can rest assured to buy them.
The arm length is an important part of the size of the glasses.
Spectacle frames are standard optical products. Just like people's clothes and shoes, they all have their own size. Usually, specs for the size of the glasses are on the inside of the temple, on the bridge of the nose, or on the label. In general, the frames of the glasses are marked with the width of the frames, the width of the bridge of the nose, and the length of the arm. For example, the inner side of the temple is labeled: 52口 18-135, indicating the lens width of 52mm, the width of the nose bridge of 18mm, and the arm length is 135mm.
Phone can identify polarized sunglasses.
Take a mobile phone with an LCD screen, turn it to maximum brightness, and look at the LCD screen through the lenses. Make sure the lenses are parallel to the display, and then slowly rotate the phone. When the true polarized lens is rotated at a certain angle, the light from the display becomes obviously darker, or even pitch-black. If they're not dark, they're not polarized sunglasses.
The material of spectacle lens
It is not only based on the refractive index to select but also depends on the material of the spectacle lens. Then there are several types of materials for myopia glasses. For example, there are glass, resin, and better PC lenses. There are also obvious differences between the three materials. The use rate of glass lenses is not high now. The myopia lenses that you often see are mainly resin lenses. These resin lenses are more suitable for wearing. Also, you can choose PC lenses. There are many PC lenses on the market. This kind of lens is very light, high toughness, and not easy to break, so it is also very popular with everyone. These three materials have their own advantages and disadvantages, so decide which one to buy according to your needs.
Take Frame material selection seriously.
When choosing a frame, try to choose a light frame. At present, the glass frame material is relatively light titanium, tungsten carbon, TR90, and so on. Now based on the plate spectacle frame, the new plate spectacle frame implements thin processing, so the whole spectacle frame has become light up. You can use rimless light glasses. Usually, the nose pad will leave an indentation, possibly because the glasses are too heavy. Changing some light glasses can improve the problem of indentation of the nose pads.
Adjust the nose pad
The height of the nose pad is adjusted by first holding the glasses with one hand and holding the nose pad with pliers with the other. Then the pliers are lifted up and the nose pad is moved down until the glasses are in the correct position on the face. The asymmetrical adjustment method is to first hold the frame of the eyeglasses with one hand, the other hand clamps the nasal plate with pliers. Then twist it in the direction of the correct tray position so that the surface of the tray is in contact with the two sides of the nose. Wrap one side of the lens of the glasses to be operated with a cloth first to prevent the screwdriver from slipping and scraping the lens during the operation. Don't scratch your glasses by adjusting your nose pad.
