If you have a high prescription, you will know the discomfort of thick, heavy lenses that can make your glasses aesthetically unappealing and uncomfortable to wear. High-index lenses are the solution: technologically advanced lenses that are thinner and lighter, while providing the same or better optical correction. At CristalesGafas, we explain everything about them.
What Are High-Index Lenses?
High-index lenses are manufactured from materials with a higher refractive index than standard lenses. The refractive index measures the efficiency with which a material bends light. The higher the index, the more light a thinner lens can bend — meaning that for the same prescription, a high-index lens will be significantly thinner than a standard lens.
Refractive Index: What Does It Mean?
- Standard index (1.50): The most basic and economical option. Suitable for mild prescriptions.
- Mid-index (1.56-1.60): Slightly thinner than standard, good for moderate prescriptions.
- High-index (1.67): Significantly thinner. Recommended for prescriptions above ±4 dioptres.
- Ultra-high-index (1.74): The thinnest and lightest option. Ideal for prescriptions above ±6 dioptres.
Benefits of High-Index Lenses
1. Much Thinner and Lighter
The primary benefit is obvious: high-index lenses are significantly thinner and lighter than standard lenses for the same prescription. This makes them more comfortable to wear all day and more aesthetically pleasing in any type of frame.
2. Suitable for Any Type of Frame
Because they are thinner, high-index lenses are compatible with a wider variety of frames, including rimless and semi-rimless styles that simply cannot accommodate very thick lenses.
3. Less Visual Distortion
High-index lenses, especially those of 1.67 and above, tend to offer less peripheral visual distortion compared to standard lenses for the same prescription.
Which Index Should I Choose?
The choice of refractive index depends on your prescription. At CristalesGafas, our optometrists recommend the most appropriate index based on your prescription values (sphere, cylinder, and axis), allowing you to enjoy thin, comfortable, and aesthetically pleasing lenses without paying more than necessary.
At CristalesGafas, we offer all refractive indices from 1.50 to 1.74, with anti-scratch coating included as standard. Contact us for personalised advice on which index is best for your prescription.