Classic clarity
A well-established, lightweight plastic lens material with very good optical clarity. An excellent, economical choice for low to moderate prescriptions.
Best for: mild powers, everyday glasses, Eco and bifocal lenses.
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The right material for your prescription.
Optolite lenses come in six indexes, from classic 1.50 CR-39 to ultra-thin 1.74. Higher index can reduce thickness for the same power — your prescription, frame and fitting determine the final result.
Thickness explorer
Watch the lens get thinner.
Choose an index and slide the prescription. Minus lenses (for short-sight) are thickest at the edge; plus lenses (for long-sight) are thickest in the centre. The dashed outline shows a 1.50 lens at the same power.
Thickness explorer
See what index does to your lens.
—Approx. edge thickness
—thinner than 1.50 at this power
Illustrative estimate for a 60 mm round lens. Actual thickness depends on your frame size and shape, fitting, lens design and diameter.
Six indexes
Meet the materials.
The everyday upgrade
A step thinner and lighter than 1.50. A popular all-round option for moderate prescriptions in finished single vision lenses.
Best for: moderate powers, stock single vision.
Light and tough
Polycarbonate is light and impact-resistant, making it a favourite for children, sports and active lifestyles, and for rimless or drilled frames.
Best for: kids, sport, safety-conscious wearers, rimless.
Slim and balanced
A thinner high-index option with a good balance of slimness and clarity. Works well for moderate to higher prescriptions and semi-rimless frames.
Best for: moderate-to-strong powers, stylish thin frames.
Noticeably thinner
For stronger prescriptions, 1.67 visibly reduces edge or centre thickness and weight — a more refined look in more frame styles.
Best for: strong powers, larger frames.
The thinnest in the range
Optolite’s thinnest index, intended for very strong prescriptions where every fraction of a millimetre counts.
Best for: very high powers.
How to choose
A simple rule of thumb.
Your optician will recommend the best index for your prescription and frame. As a starting point:
General guidance only. Availability varies by lens design and finish — see each lens page.
Up to ±2.001.50 CR-39 or 1.56 Mid index
±2.25 to ±4.001.56 Mid index, 1.59 Polycarbonate or 1.60
±4.25 to ±6.001.60 or 1.67 High index
Beyond ±6.001.67 High index or 1.74 Ultra-thin
Children & sport1.59 Polycarbonate
Beyond the index
Three things that also change thickness.
01
Frame size
Smaller, rounder frames cut away the thickest part of a minus lens. Large frames need a bigger lens blank and show more edge.
02
Fitting
Centring the lens accurately on your pupils keeps thickness balanced and vision sharp.
03
Frame style
Full-rim frames hide edge thickness; rimless and semi-rimless show it — a reason to choose a higher index or polycarbonate.
Questions
Frequently asked questions
What does lens index mean?
The refractive index describes how strongly a material bends light. A higher-index material bends light more, so it needs less curvature — and less thickness — to give the same power.
Which is the thinnest Optolite lens?
1.74 is the thinnest index in the Optolite range and is intended for strong prescriptions.
Is polycarbonate good for children?
1.59 polycarbonate is light and impact-resistant, which is why it is a popular choice for children, sports and rimless or drilled frames.
Is a 1.50 CR-39 lens a good choice?
Yes, for low to moderate prescriptions. CR-39 is a well-established lens material with very good optical clarity.
Made in India · Designed in Germany
Ask for Optolite by name.
Optolite lenses are supplied through opticians and optical partners. Talk to us about the right lens, or about stocking the collection.