What Are Progressive Lenses?
Progressive lenses also called multifocal lenses, have three prescriptions in one pair of glasses, which allows you to see near, middle-distance, and far objects without changing your glasses.
The traditional glasses have telltale lines in the lenses, while the progressive lenses are an update on bifocal and trifocal lenses. Progressive lenses have a seamless look. Sometimes, they are called no-line bifocals. The more accurate name is no-line trifocals.
Progressive lenses are typically designed for people over 40 years old who are both nearsighted and farsighted. With the progressive lenses, there is no need for you to change the nearsightedness eyeglasses and the farsightedness eyeglasses constantly.
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.
Method of taking off the contact lens
Wash your hands before removing contact lenses, and be careful not to leave long fingernails, to avoid contamination of the lenses by bacteria and nail scratches. Look up, open the upper and lower eyelids with the left index finger and right middle finger. Pinch the middle and lower edge of the lens gently with the thumb and index finger of the right hand, and remove the lens. You can use the index finger first to move the lens down, and then gently pinch the middle and lower edge of the lens with the thumb and index finger belly, and take off the lens.
What Are Anti-Glare Glasses?
Anti-glare glasses are made with lenses that have an anti-glare coating or anti-reflective coating. This is an extremely thin layer placed on the lens itself so as to remove any reflections you might see from the surface of the glasses. This improves your vision by reducing the amount of glare that reflects off of your lenses.
How to Choose Glasses for Diamond Face Shape?
After learning the features of diamond face shape, you should know how to choose glasses for diamond face shape. Since there are a lot of pointed features on the face, the best option is to use eyeglasses that have soft rounded curves instead of harshly pointed angles. So, look at the following advice.
Cat eyeglasses: Cat eyeglasses would be a good choice for a diamond face shape. These glasses frames have rounded bottoms so as to hide away the pointed chin and the narrow jawline of the diamond.
Round eyeglasses: Round eyeglasses are also suitable for diamond face shape because the round curve of the glasses hides the sharpness of the pointed chin. Glasses with colored frames are appealing in the case of diamond face shape people.
The advantages are not the same.
The cellulose acetate frame is acetate plastic, belonging to a kind of thermoplastic material, and it is a material for nearly 20 years. It is widely used in the glasses industry material. Now with the progress of processing technology, it can be divided into plate and injection molding. The acrylic frame of the propionic acid fiber belongs to a kind of thermoplastic material. The appearance is transparent. The main feature is that the material density is high. They are hard to burn and are not easy to change color, with Impact resistance. It has softness, dimensional stability, and good processing formability. Many high-grade plate glasses are based on these high-quality plates, so the quality is more reliable. It is designed for a large number of people and the pursuit of quality of life students, especially for women.
Features of pure titanium glasses frame
Due to the lightweight (ordinary nickel-based alloy frame weight 48%-60%), high strength, corrosion resistance, surface easy coloring, beautiful and durable features of spectacle frame made of pure titanium, they have been loved by most consumers. But the elastic modulus of pure titanium is higher (about 120GPa). The temples of the frames made from them are not elastic enough. After wearing the glasses for a period of time, the temples of the glasses need to be adjusted due to the relaxation of the stress. The processing plasticity of titanium metal is worse than that of other metal materials, so the processing technology of its wire is difficult. The surface quality is difficult to control, and the technical content is high. The surface quality of pure titanium wire produced by a few domestic manufacturers is poor.