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| What we offer | | Thin and Light Lenses | | Rimless Frames | |
Thin & Light Lenses
Lenses needn’t be thick and heavy. This is a wide range of thinner materials, which can reduce thickness and weight by up to 45%. These thinner lenses are often referred to as ‘high index’.
Lens IndexEvery lens material has what is referred to as a ‘refractive index’. The index is a numerical figure and for lenses ranges from1.5 to 1.9.The higher the index, the thinner the lens is.
Lenses are classified as being either ‘Standard, Mid, High or Super High Index’. Both Glass and Plastic lenses are available in all four types.
| LENS TYPE | LENS INDEX | % THINNER THAN STANDARD 1.5 LENSES |
| Standard Index | 1.5 | This is normal thickness |
| Mid Index | 1.6 | Approx 30 % thinner |
| High Index | Varies from 1.67 to 1.7 | Up to 40 % thinner |
| Super High Index | Varies from 1.74 to 1.9 | Up to 50 % thinner |
Glass or Plastic?
Plastic lenses are not currently available in as high an index as glass. The highest index plastic is a 1.74, whereas Glass indices go up to 1.9. Very strong prescriptions will therefore be thinner in glass. For most prescriptions however, plastic is usually the first choice as it is much lighter and is safer
Other Ways of Reducing Thickness
As well as choosing a Higher Index material, there are other things that will help to reduce the thickness:
Aspheric (Flatter) Lenses
These are not as curved as regular lenses. In general the flatter the curvature of the lens, the thinner it is, both in long and shortsighted prescriptions.
Custom Surfaced Lenses
These are lenses that are custom made to the minimum thickness possible for the selected frame and individual facial dimensions. They make a big difference on longsighted prescriptions.
Thin & Light Lenses are available in clear, tinted & photochromic.