Basic lens materials are plastic, polycarbonate and glass.  Some lenses
have aspherical surface design, photochromatic (changing color under the
sun) and polarizing functions.

Plastic (CR39)
-  Suitable for all kinds of frame
-  Available in different tint
-  Refractive Index Available: 1.5, 1.56, 1.6, 1.67, 1.74.  For high prescription
wearers, we recommend using higher refractive index materials.

Polycarbonate
-  Suitable for all kinds of frame, recommend for rimless frame
-  Perfect choice for kids and athletes
-  Tough and high impact resistance

Glass
-  Only recommend for high prescription
-  Only good for full frame
-  Refractive Index Available: 1.523, 1.6, 1.7, 1.8, 1.9.
-  Heavy and more fragile than plastic, not easily scratched