Typical glasses: nearsighted glasses, farsighted glasses or presbyopic glasses, keratoconstrictor lenses, astigmatism lenses, and sunglasses.
Lenses can be divided according to material: resin lenses, glass lenses, and plexiglass.
Lenses are also distinguished between spherical and aspheric lenses
Frames can be divided into two categories according to the material: metal and non-metal; each has its corresponding advantages and disadvantages.
Metal contains pure titanium, beta, titanium alloy, and alloy material. Among them, pure titanium stability is good, not easy to corrosion, not easy to allergy, light texture is currently a relatively strong frame material, but the price is relatively high. β titanium flexibility, adjustable, and rather more cost-effective. Titanium alloy: the frame contains titanium material, high hardness and plasticity, and is a little heavier. Alloy material is more flexible, encounters external force bending, and can quickly recover; relatively cheap but will be heavier.
The non-metallic material includes TR90 and Acetate. TR90 has