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 ...
Silver halide photochromic change technology: the photosensitizer silver halide (or other photosensitizers such as silver barium, copper halide and chromium halide, etc.) is added to the resin lens...
Frame width
Too wide: If the frame width is too large, the glasses are easy to slide on the face, especially in some light exercise or facial sweat, this situation will be more obvious. At the same...
The fashion industry is setting off a wave of retro round glasses, becoming a high-profile fashion item at the moment.
Round retro glasses with its classic shape and unique charm, quickly captured ...
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 ...
eyeglass
Optical property
Clarity: Quality sunglasses lenses at any Angle to see the object should be clear, no deformation, no double shadow. You can rotate the lens slightly by observing distant ...
