What does index 1.6 mean in lenses?

Are you curious why more and more eyeglass wearers are opting for index 1.6 lenses? These lenses are lighter, thinner and offer clear vision without the bulk of standard lenses. Perfect for those who have stronger strength and don't want to compromise on comfort or style. But what exactly does the “index 1.6” mean? In this blog, we explain what makes this lens option unique and why it can be a smart choice for your next pair of glasses.

What are 1.6 index lenses?

The term “index 1.6” refers to the thickness and refractive properties of an eyeglass lens. A higher index means thinner lenses with better visual clarity for higher strengths.

Index 1.6 lenses offer an ideal balance between clear vision and comfort, especially for people with stronger strength. But what exactly does the 1.6 index mean, and why should you choose it? Find out all about this popular glass option in our blog.

What is an Eyeglass Index?

The index of an eyeglass lens refers to the refractive index, or how strongly the lens can bend light. In the case of spectacle lenses, a higher index means that the lens is stronger in refraction, so that it can be cut thinner. This is especially important for people with higher strength, because without this high index, the glass would become too thick and heavy. Here is an overview:

• Standard index (1.5)
  Thick and usually only suitable for low strengths
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• Index 1.6
  Thinner than standard, ideal for medium strengths
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• Higher indexes (1.67, 1.74)
  Even thinner, designed for high strengths

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What are the benefits of index 1.6?

• Thinner and lighter
  Lenses with index 1.6 are approximately 25% thinner than the standard index 1.5. This makes them lighter and more aesthetically pleasing, as they stick out less from the frame.
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• High clarity and quality
  Due to the higher refractive power, a 1.6 index glass offers a sharp image, which is particularly advantageous for people with a deviation of -4 or +4 strength.
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• More frame choices
  Because the lenses are thinner, they fit better into a wider range of frames without looking thick and heavy.

Is index 1.6 suitable for everyone?

Not necessarily. Choosing the right glass index depends on your strength and personal preferences for comfort and aesthetics. Here are a few rules of thumb:

• Low strength (-2 to +2)
  The standard index is often sufficient, unless you want thinner lenses.
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• Medium strength (-2 to -4 and +2 to +4)
  Index 1.6 offers a good balance between thinness and cost.
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• High strength (above -4 or +4
  ‍Higher indexes such as 1.67 or 1.74 may be preferred for maximum thinness.
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With 1.6 lenses, we offer an option that is ideal for many strengths without making the glass too heavy or vulnerable.

Seeh now also offers the option for single computer glasses with a glass thickness of 1.6! With these thinner lenses, we offer an even more elegant option for screen workers, without sacrificing clarity or comfort. Thin lenses make glasses less heavy and provide a sleek and professional appearance.

Frequently asked questions

Why is a higher index more expensive?
‍A higher index is more expensive because the production process is more complicated and the materials themselves are more expensive. High-index lenses offer a sleeker, lighter and more comfortable design, which makes them much more attractive, especially for high-strength people. In addition, these lenses provide a sharper and brighter viewing experience, thanks to better optical properties and necessary coatings to reduce reflections and scratches.
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Are index 1.6 lenses scratch-resistant?
‍Yes, lenses with an index of 1.6 are scratch-resistant because they have our standard scratch-resistant coating. Scratch resistance can be further improved with additional coatings such as the Ultra coat. With this coating, the glass filters out annoying glare during the day and water, grease, dirt and dust are less likely to adhere to the glass.
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Are these lenses suitable for all frames?
‍Index 1.6 lenses are suitable for most frames. This applies to both our computer glasses and sunglasses, provided that the frame is specifically designed to support higher index lenses. These lenses offer a thinner profile, which is particularly useful for higher strengths and offers aesthetic benefits without sacrificing strength.

We see that customers who want a clear vision without compromising on thickness and style often opt for index 1.6. The result? Happy employees who can work safely and comfortably, with lenses that are less sensitive to damage and stay clear for a long time.

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