"Good sunglasses have three standards: UV blocking is much more, visible light blocking is less, and the curvature is similar to the curvature of the cornea." the expert said. It is undeniable that the quality of today's sunglasses is mixed. Many sunglasses not only have problems with the quality of the paint that blocks light, but also the arc design is not scientific. It should be emphasized that although the slightly larger sunglasses are more beautiful and more popular, they will be deformed after being worn (especially when looking down), and there will be dizziness and eye pain after wearing for a long time.
"The curvature of the lens is too large (close to the spherical surface) or too small (close to the plane) will affect the refractive index of the lens to the light, so that the object seen is uneven, long-term wear is easy to make the eyes feel tired, dry, and damage the vision." Experts pointed out In general, the curvature between the center and the edge of the cornea is about 10-15 degrees, so the curvature of the lens is also preferably within this range. "First of all, we must ensure that the curvature of the lens is no problem, and then consider whether it is beautiful." The expert gave the reader a trick: short-faced should wear enhanced upper frame, transparent lower frame, long-faced glasses suitable for enhanced upper and lower frames, square face fit square lenses, pointed face for butterfly sunglasses.