Polycarbonate vs. CR-39; why does material choice matter?
When it comes to blue light glasses, the choice of material is crucial. Below you can see at a glance why CR-39 is a superior choice over polycarbonate in everyday life:
|
Feature |
Polycarbonate (PC) |
CR-39 |
|
Abbe value → image resolution and clarity |
~30 → more color edges and a restless image |
~58 → natural color reproduction and clearer view |
|
Scratching |
Soft material, sensitive to scratches |
Naturally harder and withstands everyday use brilliantly |
|
Impact resistance |
Very high → therefore the standard for safety glasses |
Excellent impact resistance for everyday use |
|
Refractive index / feel |
n≈1.586 → thinner, but may feel flimsy and plasticky |
n≈1.498 → slightly thicker, firmer and higher quality feel |
|
Material & health |
BPA-based plastic |
Naturally BPA-free |
|
Manufacturing process |
Injection molding at high temperatures (~280–320 °C) |
Low temperature casting (≤ 95 °C) |
|
Price |
Cheaper |
More valuable, but optically superior |
Even small choices can make a big difference in your well-being. The same goes for lens materials: what your lenses are made of directly affects how the world looks through your eyes and how comfortable your glasses feel in everyday life.
Polycarbonate (PC) is a well-established material in protective eyewear and sports where impact resistance is a priority. But when it comes to screen work, natural colors, and long-term viewing comfort, CR-39 offers a completely different experience .
North Ray relies on CR-39 for its lens materials and we'll tell you why.
Clarity of vision starts with the Abbe value
CR-39 has an Abbe value of around 58, while polycarbonate has a value of around 30. The higher the Abbe value, the less chromatic aberration of light, meaning fewer color fringing, fewer “halo” effects, more natural color reproduction, and a more relaxed viewing experience.
Color fringing refers to the phenomenon where faint bluish, yellowish, or purple hues appear at the edges of bright or dark objects, especially at the periphery of the eye or during rapid movement. This phenomenon is caused by the fact that different colors (wavelengths) are refracted slightly differently through the lens. In practice, the view through the lens can appear blurry or restless, and the eyes tire more quickly.
This is where CR-39 material shines: the image remains clear and calm, colors appear natural and the eyes can endure longer. When you choose CR-39, you see without disturbing color errors and everyday life looks sharper and your eyes feel more relaxed. CR-39 reproduces colors correctly and gives the glasses a solid, high-quality feel that makes them comfortable to wear day after day.
A tough lens that keeps up with you on the go
Polycarbonate is a soft material and therefore easily scratched. CR-39 is a naturally harder optical plastic and can withstand everyday use. The lens remains bright, scratch-free and clear day after day.
Blue light protection that works through the entire lens
North Ray's blue light technology is not a coating added to the surface, but works through the entire lens material. We use carefully selected pigments designed to support circadian rhythms and protect your precious eyes in a researched and safe way.
Because the pigment is part of the entire lens, the filtering is uniform from all viewing angles. The view through the lens remains bright and calm, without disturbing color distortion. The light tint brings a pleasant balance, but the world still looks natural.
The lens filtration profiles have been developed together with top wellness and optical professionals to result in a solution that supports both clarity of vision and overall well-being.
The end result is a technically accurate yet visually gentle lens that makes viewing smooth and effortless for hours.
The CR-39 difference: a sturdy and reliable lens
Polycarbonate's high refractive index makes it thinner, which can be an advantage at high power levels. CR-39 is slightly thicker, and it is this small difference that makes the lens more comfortable to wear.
Many people find CR-39 to feel sturdier and of higher quality in the hand and on the face. It fits the frame snugly and doesn't feel flimsy or too plasticky. In everyday use, the difference in thickness is practically imperceptible, but the feeling of quality is even greater.
The number one safety glasses vs. the best everyday companion
Polycarbonate is still the standard choice for safety glasses, as it is exceptionally impact resistant, making it suitable for safety glasses, children's wear and sports. However, North Ray's products focus on optical quality and comfort. CR-39 offers excellent everyday durability and, above all, a clearer, calmer view that makes viewing natural and effortless.
The best choice for your body and the environment; BPA-free CR-39
Polycarbonate is a BPA-based plastic and when it is heated, exposed to the sun or its surface is broken, it can release BPA. This phenomenon has been observed especially in drinks bottles and food containers, but the same principle applies to all polycarbonate. Although authorities estimate that exposure from glasses is low, many people still want to avoid BPA altogether. CR-39 is a worry-free option in this regard, as it is naturally completely BPA-free.
BPA is also a problematic substance from an environmental perspective. It is classified as a substance of particular concern in the EU because it disrupts hormone function and has been linked to reproductive health issues, for example. It has also been found in landfill leachate and natural water bodies, where it does not break down easily and can accumulate in organisms. By choosing a BPA-free material, such as CR-39, you can reduce your own footprint and support both your own well-being and the well-being of the environment.
Polycarbonate is made from bisphenol A (BPA) and injection molded at high temperatures, which increases energy consumption in manufacturing. CR-39, on the other hand, is molded and polymerized at significantly lower temperatures, making the process more environmentally friendly in nature.
When you choose North Ray CR-39 lenses, you get the best combination of clear, bright vision without color fringing, natural colors, and a lens that feels high-quality in your hand. It's also a more environmentally sustainable and completely BPA-free option - without unnecessary chemical risks.
That's why North Ray's choice for your body and your eyes is clear: CR-39 is the best lens material for you and the environment. You'll definitely notice the difference every time you look at it.
