Lens Index
Discover which lens index is best for your vision needs
What is lens index?
Lens index or refractive index is a numerical representation of the thickness of your lenses. As this number increases, the lenses become thinner. The index indicates how efficiently light is bent as it passes through the lens.
Lens
Index
What is lens index?
Lens index or refractive index is a numerical representation of the thickness of your lenses.
As this number increases, the lenses become thinner. The index indicates how efficiently light is bent as it passes through the lens.
High lens index
Thinner lenses, besides being lighter, more comfortable, and visually pleasing, cater to a wider range of vision needs, including high prescriptions.
High lens index
Thinner lenses, besides being lighter, more comfortable, and visually pleasing, cater to a wider range of vision needs, including high prescriptions.
Low lens index
Low lens index
Which lens index is best for you?
The choice between lenses depends on your prescription and lifestyle. When reading your prescription note that the SPH value indicates the amount of lens power prescribed for (-) or (+). The CYL value is not always included in prescriptions; it indicates the power of your astigmatism correction.
Which lens index is best for you?
The choice between lenses depends on your prescription and lifestyle. When reading your prescription note that the SPH value indicates the amount of lens power prescribed for (-) or (+).
The CYL value is not always included in prescriptions; it indicates the power of your astigmatism correction.
Check out our lens comparison guide below to see the qualities of each lens.
Check out our lens comparison guide below to see the qualities of each lens.
Lens thickness based on prescription
Lenses can be thickest in the center or at the edges, depending on the prescription. Our aspheric lenses reduce central thickness as they have a flatter curve.
Plus lenses
These lenses are thickest in the center, like a magnifying glass. They are used to correct farsightedness (hyperopia). The numerical prescription is always marked with a plus (+) symbol.
Minus lenses
These lenses are thickest on the edges. They are used to correct nearsightedness (myopia). The numerical prescription is always marked with a minus (-) symbol.
Lens thickness based on prescription
Lenses can be thickest in the center or at the edges, depending on the prescription. Our aspheric lenses reduce central thickness as they have a flatter curve.
Plus lenses
These lenses are thickest in the center, like a magnifying glass. They are used to correct farsightedness (hyperopia). The numerical prescription is always marked with a plus (+) symbol.
Minus lenses
These lenses are thickest on the edges. They are used to correct nearsightedness (myopia). The numerical prescription is always marked with a minus (-) symbol.
Available lens add-ons for each index
Enjoy your optical experience to the fullest with the lens features that best fit your lifestyle.
Available lens add-ons for each index
Enjoy your optical experience to the fullest with the lens features that best fit your lifestyle.
Choosing a frame for low-index lenses
Do
- Consider the thickness of the lens: low-index lenses are thicker than high-index lenses, so choose a frame that’s thicker.
- Prioritize frame size: smaller frames ensure a comfortable fit and a lighter weight.
- Consider aesthetics: your glasses should match your style and face shape. There are many frame options available.
Don't
- Choose rimless or semi-rimless frames: these styles may not support the weight of low-index lenses effectively.
- Disregard lens treatments: treatments like anti-reflective coatings can make lenses appear thinner by reducing glare.
- Overlook the fit: if your glasses are too loose or too tight, they can cause discomfort.
Do
- Consider the thickness of the lens: low-index lenses are thicker than high-index lenses, so choose a frame that’s thicker.
- Prioritize frame size: smaller frames ensure a comfortable fit and a lighter weight.
- Consider aesthetics: your glasses should match your style and face shape. There are many frame options available.
Don't
- Choose rimless or semi-rimless frames: these styles may not support the weight of low-index lenses effectively.
- Disregard lens treatments: treatments like anti-reflective coatings can make lenses appear thinner by reducing glare.
- Overlook the fit: if your glasses are too loose or too tight, they can cause discomfort.
How to shop for lenses with the best index for you
How to shop for lenses with the best index for you:
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Got questions about eye care? We’re here to help.
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Speak to a
certified optician
Got questions about eye care?
We’re here to help. For guidance you can trust, ask our in-house opticians.
FAQs
A 1.50 index lens refers to a type of lens with a refractive index of 1.50. In the case of a 1.50 index lens, it means that the lens material has a moderate level of light-bending capability. These lenses are generally thicker than higher-index lenses. They are often used for prescriptions with moderate levels of correction.
There is obvious sign that indicates whether the lenses are high or low index. To determine the index of your lenses, you need to check your glasses prescription or the receipt provided at purchase, where the lens index is often listed. If you can't find this information, it's best to contact your optician or eyewear retailer for your prescription details.
Yes, lens thickness matters, particularly for comfort, aesthetics and vision quality (depending on your prescription). High index lenses are designed to manipulate light more efficiently, making them essential for those with stronger prescriptions. They are thinner, lighter and visually pleasing which is why there are highly preferred.
If your eye needs don't require high index lenses, you can opt in for low index lenses which are more budget-friendly but can affect your comfort and appearance preferences due to their thickness.
Astigmatism can affect lens thickness because it typically requires a more complex lens shape to correct uneven focusing of light. If you have moderate to high astigmatism, your lenses will be thicker. Choosing high index lenses is a great option to obtain thinner lenses for an improved aesthetic.
Our thinnest lens is the ultra thin 1.74 index lens. It is 60% thinner than the basic lens making it more lightweight, extra comfortable and perfect for those with stronger prescriptions.
High-index lenses such as our 1.74 lens are considered an investment due to the sleek thinness of the lens and the longer labour process. As it is our most premium package, the price reflects this.