Blue light blocking lenses are a type of functional eyewear designed to selectively filter out harmful short-wave blue light (415–445 nm) while preserving beneficial blue light (455–505 nm) through coating reflection, substrate absorption, or a dual-action combination of both. Their core function is to alleviate visual fatigue caused by prolonged exposure to digital screens, rather than the heavily marketed claims of "preventing myopia" or "preventing macular degeneration."
Core Technologies and National Standards
Currently, mainstream blue light blocking technologies fall into three categories:
1. Coating Reflection Technology: Nanometer-scale metal oxide films are coated onto the lens surface to reflect harmful blue light through interference effects. This method can achieve a blocking rate of 30% to 50%, with a visible light loss of about 8%, giving the lens a pale yellow tint.
2. Substrate Absorption Technology: Benzotriazole-based blue light absorbers are added directly into the raw lens material, allowing the substrate itself to absorb blue light. The protective efficacy remains unaffected by coating wear, though the lens also exhibits a slight yellowish base color.
3. Dual-Action Protection Technology: This approach combines both methods mentioned above to further optimize filtering precision, balancing light transmittance with long-term protection stability.
China's GB/T 38120-2019 standard establishes strict, mandatory requirements for qualified blue light blocking lenses:
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Harmful blue light (415–445 nm) transmittance must be ≤80% (filtering out at least 20%).
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Beneficial blue light (455–500 nm) transmittance must be ≥80%.
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Visible light transmittance must be ≥80%, ensuring the lenses are not too dark to interfere with normal vision.
Target Audience and Usage Scenarios
Not everyone needs to wear blue light blocking lenses. They serve as an effective eye-care aid only when accurately matched to the user:
Recommended For:
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Heavy digital users who continuously stare at electronic screens for more than 6 to 8 hours a day.
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Professionals working on computers in low-light or nighttime environments.
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Individuals suffering from dry eye syndrome or other ocular surface issues.
Wearing qualified blue light blocking lenses can reduce harsh glare, soothing dryness, soreness, and swelling.
Not Recommended For:
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Children under 12 whose visual systems are still developing.
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Graphic designers and painters who require high color accuracy.
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Individuals with minimal daily screen time.
Long-term use for these groups might interfere with ocular development or impair color judgment.
There is no need to wear blue light blocking lenses all day long. They are best reserved for extended periods of computer or phone use. For outdoor activities or reading printed materials, switching back to regular lenses will offer a more comfortable visual experience.
Post time: Jul-03-2026