When choosing eyeglass lenses, you often hear the term “refractive index”, but what exactly does it mean and why is it important?

What is the refractive index?

The refractive index is a value that shows how much a material (e.g. the lens material) refracts light. The higher the refractive index, the better the lens is able to focus light, so thinner lenses can be produced with the same diopter value.

Why is this important in optics?

Lenses with a higher refractive index are thinner and lighter, which is not only aesthetically beneficial, but also provides more comfort. This is especially important for higher diopters, where the thickness of the lens can be greater.

Example: If you need glasses with high diopters, it is worth choosing lenses with a high refractive index to avoid the wearing of heavy and thick lenses.