Feel with the eye
Clarity: After wearing glasses, under the normal eye distance, such as looking at an eye chart at 5 meters or a book or computer screen at 30-40 centimeters, you should be able to...
1. Different functions
Ordinary sunglasses use the color dyed on the tinted lenses to weaken all the light into the eyes, but all the glare, refracted light and scattered light enter the eyes, whic...
Choose the right sunglasses
Uv protection: To ensure that sunglasses can effectively block ultraviolet light, the label is usually marked with UV400 and other signs, indicating that it can block mo...
Plate frames are a type of eyeglass frame made of plate materials, which have become increasingly popular in the market in recent years. Plate materials are usually a plastic synthetic mater...
What is cellulose acetate?
Cellulose acetate refers to a thermoplastic resin obtained by esterification with acetic acid as a solvent and acetic anhydride as an acetylating agent under the action o...
Effect of refractive index on visual acuity in the aged
Lens thickness
For the elderly with high myopia or farsightedness, it is more appropriate to choose a lens with a high refractive index. The ...