About Lens Index & Lens Materials

If you've got questions about lens index and lens materials, then this is the guide what you want to look first.

What’s Lens Index?

Lens index is a number that describes how thick or thin your lenses are. The higher a lens' index is, the thinner it becomes. Higher prescriptions require higher index lenses, while lower prescriptions require lower index lenses.

What Are High Index Lenses And What’s The Difference?

High index lenses are thinner, more powerful lenses. They're lightweight and stylish, but are mostly reserved for those with higher vision correction needs. While most prescriptions are compatible with more than one specific index, it's up to you to decide which one fits your personal needs!

The difference between your glasses' lens index can make a huge impact. Deciding which you should get depends on your prescription and your lifestyle. Thicker lenses are more affordable, but can only accommodate lower vision correction needs. Thinner lenses are lightweight (and more stylish) and can accommodate many kinds of vision needs, including higher prescriptions. In terms of balancing price and quality, 1.59 index polycarbonate lenses accommodate most prescriptions and are extra durable.

What Should We Know About Lens Materials?

There are two things you need to consider when deciding which lens material will work best for you: prescription and lifestyle. While mild prescriptions may work with any lens materials, stronger prescriptions may require a specific lens material. Additionally, children and people with active lifestyles may opt for the added protection of impact-resistant lenses.

What Lens Materials & Lens Index are avaiable by Leotony Eyewear? 


MR is an optical material with high refractive index, high Abbe number, low specific gravity and high impact resistance. 

1.56 MR lenses are recommended for low RX range below +2.00/-2.00.

1.61 MR lenses are recommended for RX range +3.00 /-5.75 or below.

1.67 MR lenses are recommended for RX range +7.00/ -9.00 or below.


Polycarbonate lens is thinner and lighter and also shatter-proof,making it the optimal choice for kids and active adults.

1.61 PC lenses are recommended for RX range +3.00/ -4.75.