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Clear vs yellow (amber) blue light lenses: what is the difference?

By Spektrum Glasses Editorial Team · Published 2026-08-13 · Updated 2026-09-11 · Facts re-checked 2026-09-11 How this page is written and checked: our editorial method · how we verify claims

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Short answer

PROSPEK’s clear lens stays near-colorless (91.6% visible light transmission) and filters blue light in a taper - 99.99% at 400 nm down to 33.1% at 450 nm. The yellow evening lens carries a visible tint (about 65% visible transmission) and filters a flatter 98% across the whole 400-500 nm blue band, including the 460-480 nm sub-band, at the cost of color neutrality and brightness.

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The core difference: a coating versus a tint

PROSPEK’s clear lens is a light, essentially colorless coating. The yellow evening lens carries a visible tint you can see the moment you put it on. That difference is functional, not cosmetic — the two lenses are built to do different jobs at different points in the day. The clear lens holds 91.6% visible (photopic) light transmission, so colors on a screen or a printed page read close to normal. The yellow evening lens’s visible transmission runs about 65%, because more of the blue-heavy end of the spectrum has been filtered out, at the cost of overall brightness and color neutrality — whites and screens read slightly warm through it. Both figures come from the same COLTS Laboratories report, O-SPG111015 (A2LA-accredited to ISO/IEC 17025, spectral transmittance measured per ANSI Z80.3). The report’s own sample designation for the tinted lens is “amber”; PROSPEK’s copy calls it yellow, because that is the color it actually is.

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How much blue light each one filters, by wavelength

The two lenses don’t just filter different amounts of blue light — they filter it in a different shape across the spectrum. Clear lens (COLTS O-SPG111015): Yellow evening lens (COLTS O-SPG111015): The clear lens is strongest right at the UV/violet edge and tapers fast — by 450 nm it is filtering about a third of the light reaching that wavelength. The yellow lens holds a high filtering rate across the entire 400-500 nm band instead of tapering, including at 460-480 nm, the narrower sub-band the lab report calls out separately.

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Why “clear” can’t match a tint, and why a bare percentage misleads

A lens that stays visually clear has to let most visible light through, so it cannot sustain a high filtering rate across the whole 400-500 nm band without the tint shifting toward yellow or orange. That is a property of tint and transmission, not a manufacturing shortfall, and it shows up elsewhere in the PROSPEK lineup too: the clear lens used on our ZENOX frames measures about 52% average filtering across the 400-500 nm blue band, with 100% UV filtered. That’s a different figure from the primary clear lens above because it is an average across a band rather than four discrete wavelength points, but it illustrates the same tradeoff — a clear lens filters part of the band, not all of it. This is also why this page never states a percentage without the wavelength or band it was measured over. “Filters 99% of blue light,” on its own, could describe a strong result at a single wavelength near UV or a much weaker one averaged across the visible blue range. There’s no way to tell which without the band attached. The clear lens’s sample group also passed ANSI Z80.3 transmittance and chromaticity testing, all samples, at the ISO/IEC 17025-accredited lab. That standard measures light transmittance and color — not how accurately a lens grinds a reading power. The two are unrelated tests, and a Z80.3 pass says nothing about the second one.

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Neither lens is built or tested for night driving

Independent guidance is skeptical of tinted lenses after dark. The UK College of Optometrists advises drivers to wear their normal glasses at night and states that yellow-tinted lenses are not proven to help and may make dark parts of the road harder to see; NHTSA guidance similarly warns that any tinted lens after dark reduces the light reaching the eye. Separately, an October 2025 IIHS/HLDI analysis of roughly 24 million U.S. crashes from 2015 to 2023 found glare was a contributing factor in only 1 to 2 per 1,000 nighttime crashes, with no increase over the decade even as headlight glare complaints have risen. That data speaks to crash rates, not to comfort — a 2026 AAA national survey found about six in ten drivers report struggling with headlight glare, which is a separate, real discomfort finding the crash data doesn’t contradict. Regulators have acted on overreach in this exact category before: in a 1997 settlement, the FTC found a night-driving eyewear marketer’s safety claims unsubstantiated, banned the product’s name, and required consumer redress. PROSPEK’s yellow lens is positioned for evening screen and indoor use, not for driving, and this page makes no night-vision or crash-safety claim for either lens.

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What the research says about tint color and outcomes

Independent research on blue-light-filtering lenses in general — not specific to any one tint — gives a mixed picture. A 2017 study in PLOS ONE (Leung, Li & Kee) found that commercially available blue-light-filtering lenses reduced the calculated blue-light hazard, an optical exposure metric, by roughly 10 to 24 percent; that’s a calculated optical result, not a measured clinical outcome. A November 2025 meta-analysis in Frontiers in Neurology, pooling three randomized controlled crossover trials with actigraphy-measured sleep, found no statistically significant difference between blue-blocking and control lenses in sleep onset latency, total sleep time, sleep efficiency, or wake-after-sleep-onset. The authors describe current RCT evidence as not supporting a significant effect, while allowing that small effects remain possible. A January 2026 review in Therapeutic Advances in Ophthalmology (Khorrami-Nejad et al.) reports minimal or no significant difference in contrast sensitivity, color discrimination, or task performance versus standard lenses, and describes the evidence around eye strain and circadian outcomes as unsettled. None of this is specific to lens color — it’s the broader-category finding. It’s also why this page rests the case for the yellow lens on its measured, band-specific filtering numbers rather than on a promised outcome.

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Where clear and yellow sit in the PROSPEK lens ladder

Clear and yellow are the first two steps of a four-lens ladder built around time of day, not the only two options in the lineup. Later in the evening, PROSPEK’s orange pre-sleep lens filters 99.96% across 380-500 nm, and the red night lens filters 99.83% across the same range while also cutting green light through about 560 nm — both measured in 2026 by our lens manufacturer’s optical laboratory. Neither the orange nor the red lens is suitable for driving, day or night. Choosing between clear and yellow comes down to the hour: clear for daytime and screen work where color accuracy matters, yellow for evening use where filtering more of the blue band matters more than color neutrality.

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Where these numbers come from

Every measured figure quoted here is transcribed from a third-party laboratory report, published in full with the wavelength band and the report number: lab results. Our rule for what may appear on this page at all is on how we choose what to publish.

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Related questions

• What do orange lenses do?
• What do red lenses do?
• Do clear blue light lenses actually work?
• What percentage of blue light should glasses block?
• Why do some blue light glasses have a yellow tint?
• What does an anti-reflective coating do?

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