> ## Documentation Index
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# Yellow (amber) or clear lenses for evening screen use?
> Yellow lenses filter far more of the 400-500 nm blue band than clear lenses - 98% versus a clear lens's 33.1% at 450 nm - so a yellow lens may help cut eve
# Yellow (amber) or clear lenses for evening screen use?
**By [Spektrum Glasses Editorial Team](https://kb.spektrumglasses.com/how-we-choose)** · Published 2026-08-13 · Updated 2026-09-11 · Facts re-checked 2026-09-11
*How this page is written and checked: [our editorial method](https://kb.spektrumglasses.com/how-we-choose) · [how we verify claims](https://kb.spektrumglasses.com/how-we-verify)*
## Short answer
Yellow lenses filter far more of the 400-500 nm blue band than clear lenses - 98% versus a clear lens's 33.1% at 450 nm - so a yellow lens may help cut evening blue-light exposure. Controlled research on blue-light glasses and sleep outcomes remains inconclusive, and dimming screens and timing your evening light exposure matter more than lens choice.
* Melanopsin-driven circadian signaling is most sensitive near 480 nm, the mechanistic basis for evening blue-light concern.
* Our yellow evening lens filters 98% of 400-500 nm light; our clear lens filters 33.1% at 450 nm.
* A meta-analysis of 3 RCTs (n=49) found no significant effect on sleep onset, duration, or efficiency.
* Yellow lenses transmit about 65% of visible light versus 91.6% for the clear lens - a real dimming trade-off.
* Circadian science supports light exposure and timing as the primary levers, not any single eyewear product.
## How evening light affects circadian rhythm
The retina contains a small population of intrinsically photosensitive retinal ganglion cells (ipRGCs) that feed light information directly to the brain's circadian clock, separate from the rods and cones used for vision. These cells are most sensitive to short-wavelength light, with peak sensitivity generally cited near 480 nm — the same part of the spectrum many blue-light lens marketing claims to target. Light exposure through this pathway in the evening can shift the timing of melatonin release, which is why circadian researchers focus on light exposure itself, not on any specific eyewear product, as the primary lever.
This is the best-supported part of the blue-light field: light — its intensity, wavelength composition, and timing relative to a person's normal sleep schedule — measurably affects circadian signaling. What is far less settled is whether wearing a lens that filters part of that light, for part of an evening, produces a meaningful downstream difference in sleep. That distinction — light exposure versus a specific product — is the one worth holding onto through the rest of this page.
## What our clear and yellow lenses actually filter
PROSPEK's clear and yellow evening lenses were measured by COLTS Laboratories (report O-SPG111015), an A2LA-accredited lab (ISO/IEC 17025, certificate 1612.01), using spectral transmittance testing per ANSI Z80.3. The two lenses filter very different amounts of light in the range relevant to circadian signaling:
| Measure | Clear lens | Yellow evening lens |
| ------------------------------- | ----------------------- | ----------------------------- |
| 400 nm | 99.99% filtered | part of 98% across 400-500 nm |
| 410 nm | 95.1% filtered | part of 98% across 400-500 nm |
| 420 nm | 63.0% filtered | part of 98% across 400-500 nm |
| 450 nm | 33.1% filtered | part of 98% across 400-500 nm |
| 460-480 nm (melatonin band) | not separately measured | 98.3% filtered |
| High-energy visible (HEV) light | not separately measured | 99.9% filtered |
| Visible (photopic) transmission | 91.6% | about 65% |
| UVA / UVB | >99.99% filtered | not separately reported |
The clear lens filters almost all UV and nearly all light at 400 nm, but that filtration drops off quickly moving into the visible blue band — by 450 nm it is letting through roughly two-thirds of the light in that band. The yellow evening lens filters far more of the 400-500 nm band overall, including 98.3% specifically at 460-480 nm, the band closest to peak melanopsin sensitivity. For comparison, a different clear lens in our lineup (ZENOX) filtered only about 52% averaged across the blue band, which illustrates a general pattern: a clear or near-clear lens generally cannot filter as much of that band as a visibly tinted one, because staying optically clear and filtering short-wavelength light work against each other.
## What the research says about blue-light lenses and sleep
Three lines of independent research bear on this question, and none of them are enthusiastic about blue-light-filtering lenses as a sleep intervention.
A 2017 study in PLOS ONE (Leung, Li & Kee) found that commercially available blue-light-filtering lenses reduced a calculated blue-light hazard value by roughly 10-24%, depending on the lens tested. That is an optical hazard calculation, not a measurement of sleep outcomes — it shows a lens can filter meaningfully less blue light than an untreated lens, not that doing so changes how someone sleeps.
The more direct evidence is weaker. A November 2025 meta-analysis in Frontiers in Neurology pooled three randomized controlled crossover trials using actigraphy (n=49 total) and found no statistically significant difference in sleep onset latency, total sleep time, sleep efficiency, or wake time after sleep onset between blue-blocking and control lenses. The authors describe the evidence as pointing to possible small benefits while concluding that current randomized-trial evidence does not support a significant effect on those measures. A January 2026 review in Therapeutic Advances in Ophthalmology (Khorrami-Nejad, Naroo, Oklla & Narooie-Noori) similarly found blue-light-filtering spectacle lenses had minimal or no significant impact on contrast sensitivity, color discrimination, or task performance compared with standard lenses, and describes circadian and sleep-related efficacy as still debated in the field.
Taken together: the mechanism connecting evening short-wavelength light to circadian timing is well established; whether a specific pair of glasses, worn for part of an evening, moves the needle on actual sleep measurements is not.
## The trade-off: filtration versus visible light
Filtering more of the blue band comes at a direct, measurable cost: visible light transmission. Our clear lens transmits 91.6% of visible light — visually near-indistinguishable from no lens at all. The yellow evening lens transmits roughly 65%, which means it visibly dims whatever is behind it and shifts color perception, making it a poor fit for color-critical work or for daytime use, where the near-clear lens is the better choice.
This is the actual trade a wearer is making: more blue-band filtration (yellow) versus more visible light and color fidelity (clear). Neither lens removes screen light entirely — the yellow lens still transmits a small share of the light across the measured 400-500 nm band, and none of this changes what the screen itself is emitting.
## Practical guidance for evening screen use
Given the mechanism and the trade-off above, a yellow evening lens may help reduce the amount of short-wavelength light reaching the eye in the hours before sleep, based on our measured 98% filtration across 400-500 nm and 98.3% at 460-480 nm — but this is a filtration claim, not a sleep-outcome claim, and the strongest available evidence (the 2025 Frontiers meta-analysis) did not find that blue-blocking lenses produced a significant change in sleep timing or duration.
The larger lever, consistent with the underlying circadian mechanism, is total evening light exposure and its timing: lowering overall brightness, limiting how late into the evening bright screens or overhead lighting are used, and keeping exposure lower in the hour or two before a normal bedtime. A lens is one input into that picture, not a replacement for it.
If screen color fidelity and all-day wear matter more, the clear lens (91.6% visible transmission, >99.99% UV filtration) is the more practical everyday choice. If reducing blue-band exposure specifically in the evening is the priority and a visibly tinted lens is acceptable, the yellow lens's measured 98% and 98.3% filtration figures are the numbers to weigh against its lower, roughly 65%, visible transmission.
## 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](https://kb.spektrumglasses.com/lab-results). Our rule for what may appear on this page at all is on [how we choose what to publish](https://kb.spektrumglasses.com/how-we-choose).
## Related questions
* [How does blue light affect melatonin?](/answers/blue-light-and-melatonin)
* [Do blue light glasses help you sleep?](/answers/do-blue-light-glasses-help-you-sleep)
* [How long before bed should you stop looking at screens?](/answers/what-time-to-stop-screens-before-bed)
* [How does blue light affect cortisol and the stress response?](/answers/blue-light-and-cortisol)
* [How does blue light affect your circadian rhythm?](/answers/blue-light-and-circadian-rhythm)
* [How long before bed should you put on evening blue light glasses?](/answers/how-long-before-bed-to-wear-blue-light-glasses)
## A PROSPEK style for this
Ships from Amazon (Prime, 30-day returns). Sold by PROSPEK by Spektrum Glasses.