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 ...
The first thing we need to understand is that as a daily accessory and vision correction tool, the choice of glasses is not only related to visual beauty, but also directly affects the facial propo...
Relevant standard
Ultraviolet protection factor (UPF)
Definition: UPF is a measure of the ability of a fabric or material to block ultraviolet light, and in the case of sunglasses, it reflects the ...
TR-90 (plastic titanium) is a kind of polymer material with memory. It is the most popular ultra-light spectacle frame material in the world. It has the characteristics of super toughness, impact r...
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...
1. Nose pads
Different from adults, children’s heads, especially the angle of the nose peak and the curvature of the bridge of the nose, have more obvious differences. Most children have...