Different types of lenses and thicknesses

For the choice of lenses, it is important to keep four factors in mind: clarity of vision, comfort, safety and appearance. Therefore, it is necessary to take your time and choose the lens with patience.

Our thickness guide is related to the refractive index of each material (speed of light passing through the material). The higher the refractive index, the lower the thickness.


Glass lenses:

The glass lenses provide a striking, scratch-resistant optics, but it makes the glasses heavy and can break. It is ground and polished, which guarantees that the surface does not contain imperfections. There are different indexes 1.52, 1.7, 1.81 and 1.9.


Plastic lenses:

Plastic lenses were first introduced in the eyewear industry by the Armorlite Lens Company of California in 1947. The lenses were made of lightweight polymer and had excellent optical qualities. They are economical and durable.



Polycarbonate lenses:

Polycarbonate lenses were first introduced in the early 1970s by Gentex Corporation and it was even lighter and stronger than plastic lenses and is still one of the most preferred lens materials.



High index plastic lenses:

With the recent demand for lighter and thinner lenses, high-index plastic lenses have been created that have a high refractive index and a lower specific gravity that makes the lenses exceptionally light and thin.



Aspherical lenses:

Aspherical lenses are a recent addition to the eyewear industry. These lenses are not exactly rounded on the surface and are useful for correcting minor distortions in vision. This design also makes the lens even lighter and thinner to give it a comfortable experience.



Wavefront technology lenses:

Wavefront technology lenses are specially designed to sharpen visual clarity. The lenses are designed based on the exact measurement of the path through which light travels through the eye.



Summary of organic and mineral lens materials

   . Index 1,498 (not reduced) (organic)

    Index 1.53 (without reducing) (crystal)

    Polycarbonate lenses index 1.58

    Indices 1.6 (minimum reduction and good durability)

    Index 1.67 (mean reduction and acceptable durability)

    Index 1.70 (high reduction) (crystal)

    Index 1.74 (high reduction and rather delicate lenses)

    Index 1.8 (very high reduction) (crystal)