What Are Lens Materials?

Lens materials refer to the type of substance used to make the lenses in your glasses. Each material has different properties in terms of weight, thickness, durability, and optical clarity. Common lens materials include:

CR-39 (Plastic): Affordable, good optical quality, but thicker.

Polycarbonate: Impact-resistant, lightweight, ideal for kids and active users.

What Is Lens Index?

The lens index (or refractive index) measures how efficiently a lens material bends (refracts) light. A higher index means the lens can bend light more effectively, so less material is needed—making the lens thinner and lighter.

Here’s a quick lens index scale:

1.50 (Standard Index): Basic plastic, thicker.

1.56 (Mid-Index): Slightly thinner than standard.

1.59: Polycarbonate, impact-resistant.

1.67 (High-Index): Much thinner, great for strong prescriptions.

1.74 (Ultra High-Index): Thinnest and lightest, ideal for very strong prescriptions.