CIRCADIAN SLEEP LENS
Long-wavelength pass filter
Sleepaxa Clarte Jet Black Sleep Glasses
Amber & Red Circadian Lenses
Blocks the blue and green band that suppresses melatonin, so your body starts making it on schedule.
Size44-17-140
Front width135mm
Lens height44mm
FitSmall
ShapeCat eye
$99.00
$110.00
10% off
Free shipping to the US & EU · duties and taxes included · ships worldwide from our lab
Free shipping to the US & EU with duties and taxes included · delivered in 6–8 business days after dispatch.
One-year frame warranty · six-month lens warranty.
Cut, tinted and finished in the Sleepaxa optical laboratory.
30-day returns on zero-power glasses*
*Zero-power (non-prescription) glasses only, unworn and in original packaging. Prescription lenses are made to order and cannot be returned. Returns are shipped by the customer to our warehouse; return shipping is paid by the customer. Returns policy
Spectrometer lab reports
Third-party spectrophotometer readings for this exact lens. Every batch is verified before it ships.
Evidence
What sits behind this lens.
Every claim on this page traces back to a document you can open: a spectrophotometer report, a granted patent number on the public registry, or a peer-reviewed paper indexed by the US National Library of Medicine.
Spectrometer reports
Measured, not estimated
Third-party spectrophotometer readings for this exact lens formulation, tested to EN ISO 12312-1, ANSI Z80.3 and AS/NZS 1067.1. We publish the measured number either way, not only the flattering ones.
View measured lens data
Granted · Indian Patent Office
Two granted patents
Granted Patent IN 587746 for the dual-band NeuroCalm FLX+ lens and Granted Patent IN 597482 for Circadian560 — plus four more filings. Verifiable on the government registry.
See patent register
Peer-reviewed
PubMed-indexed research
Peer-reviewed research from our founder, published in Cureus and indexed on PubMed by the US National Library of Medicine (PMID 42524168).
Read the paperSpectral behaviour
Where this lens sits on the spectrum.
Wavelength bands and what the lens does across each one. Every batch is checked on a spectrophotometer before it ships.
Comparison
Why not just any blue-light coating?
Compare the mechanism before you choose. A coating reflects a little blue; a wavelength-selective lens absorbs a defined band and publishes the measurement.
| Sleepaxa lens | Typical blue-cut coating | Device night mode | |
|---|---|---|---|
| Blocks the melanopsin peak near 480 nm | Lab-verified | Partial, typically 10–40% | No |
| Covers the green band up to 550 nm | Red / Circadian560 lens | No | No |
| Spectrophotometer report you can open | Every batch | Rare | — |
| Granted patents | IN 587746 · IN 597482 | No | — |
| Peer-reviewed research on PubMed | Yes | No | No |
| Covers room light, not only the screen | Yes | Yes | No |
| UV protection | 100% UV400 | Varies | No |
Comparison based on our published spectrophotometer reports and on typical published specifications for generic blue-light filtering coatings and device night modes. No specific competing product is named or tested here.
Before you decide
Fit, tint and prescription.
The fitWill this frame fit me?
Look on the inside of the arm of a pair you already wear. You will find three numbers, usually printed as 52–18–145. They are, in order, the lens width, the bridge width and the arm length — all in millimetres. Match those to the frame below and the fit will be close.
| Lens width | Bridge | Arm length |
|---|---|---|
| 44-17-140 | 135mm | 44mm |
If your numbers are within about 2 mm of the frame, it will sit correctly. A narrower face suits a smaller lens width; a wider face suits a longer arm.
The lensAmber or Red — which one?
Amber is the all-day lens. Luminous transmittance around 50%, Filter Category 1, safe indoors and outdoors. It removes the blue band and part of the green band while leaving enough light through to read, cook and work. Wear it from late afternoon onwards.
Red is the night lens. Zero measured transmission from 380 to 560 nm, Filter Category 3, indoor use only. This is the one to put on two to three hours before bed, when the aim is to remove the circadian signal completely rather than reduce it.
Most people who use both wear Amber in the evening and switch to Red in the last hours before sleep. That is the reason the second-pair pairing exists.
The lensPrescription and lens index
Choose Prescription Lens and we cut the tint into a lens made to your power in our own lab. After checkout you will receive an email asking for your prescription and pupillary distance — you can also reply with a photograph of the prescription.
| Index | Suited to | Profile |
|---|---|---|
| 1.56 | Up to about ±2.00 D | Standard thickness |
| 1.61 | ±2.00 D to ±4.00 D | Thinner, lighter |
| 1.67 | ±4.00 D to ±6.00 D | Noticeably thinner edge |
| 1.74 | Above ±6.00 D | Thinnest available |
Not sure which index applies to you? Send us the prescription and our optometry team will select it for you at no extra cost.
Prescription lenses are made to order for your eyes and cannot be returned or exchanged, unless we made them incorrectly — in that case we remake them free of charge.
Everything elseShipping, returns, warranty and care
Free shipping to the US & EU with duties and taxes included · delivered in 6–8 business days after dispatch. One-year frame warranty · six-month lens warranty.
30-day returns on zero-power glasses* *Zero-power (non-prescription) glasses only, unworn and in original packaging. Prescription lenses are made to order and cannot be returned. Returns are shipped by the customer to our warehouse; return shipping is paid by the customer. Read the full returns policy.
Clean the lens with the supplied microfibre cloth only. Tinted lenses are absorptive through the full thickness of the material, so surface scratches do not change the transmission curve — but they do scatter light, which is worth avoiding.
Still deciding
Ask a clinician, not a chatbot.
Tint, prescription, lens index or frame fit — our optometry team answers directly.
Choose your second pair
The Performance Hybrid Series · Sleep
Clarte Jet Black
The smallest lens width we make, on a jet black cat eye that is as tall as it is wide.
At 44 mm the Clarte has the narrowest lens in the whole line, and at 44 mm of height it is as deep as it is wide, which are unusual proportions that give a small frame real coverage. The front measures 135 mm and the arms run 140 mm. Performance Hybrid construction throughout: an Ultem body for a hypoallergenic, low-weight feel, titanium reinforcement at the temples and bridge, about 12 grams, with MR-8 Mitsui optical-grade lens resin. This is the frame for a genuinely small face, and the cat eye angle is what stops it from looking childlike.
Two tints, two jobs
One tint for the evening, one for the edge of sleep.
Amber lensEvening0.10% measured transmission at 450 nm, the melanopsin peak, then 66.6% at 560 nm and 96.3% at 600 nm. Short wavelengths are removed almost entirely while warm light is left alone. Luminous transmittance 50.5%, Filter Category 1.
Red lensRight at the endZero measured transmission from 380 to 560 nm. The lens opens only in the long band, 49.7% at 600 nm and 92.9% at 700 nm. Luminous transmittance 14.9%, Filter Category 3, which keeps it indoors.
All figures are single-lens spectrophotometer measurements from our own laboratory reports for this lens, tested to EN ISO 12312-1, ANSI Z80.3 and AS/NZS 1067.1. Individual response varies.
Fit
Will the Clarte fit you?
If frames routinely swamp you, read the numbers inside your arm and look for a first figure under 48 mm. The Clarte's 44 mm lens is smaller than anything else we cut, and the 135 mm front is narrow to match. The 17 mm bridge is mid-width, so it does not demand the high nose bridge that the 16 mm hybrids do. At 44 mm of lens height, coverage is better than the small width would suggest.
| Frame size | 44-17-140 |
|---|---|
| Front width | 135 mm |
| Lens height | 44 mm |
| Fit | Small |
| Shape | Cat eye |
| Collection | The Performance Hybrid Series |
| Material | Ultem and titanium hybrid |
| Lens options | Amber or Red · zero power or prescription |
| UV protection | 100% UV400, both tints |
In the box
- Clarte Jet Black frame in your chosen tint
- Hard case and microfiber cleaning cloth
- Spectrophotometer report reference for your lens
- One-year frame warranty, six-month lens warranty
Shipping. Free shipping to the United States and the European Union with import duties and taxes included — nothing to pay on delivery. Rest of the world: shipping is calculated at checkout and any local duties or taxes may be payable by the recipient. In-stock zero-power orders are processed within 1–2 business days and most orders arrive within 6–8 business days after dispatch. Every order ships from our own optical laboratory.
Prescription orders. If you selected a prescription lens, our optometry team emails you after checkout to confirm your power and pupillary distance. Lenses are not cut until that confirmation, so a prescription order takes 3–7 business days longer than a zero-power one.
Returns. Zero-power (non-prescription) glasses may be returned within 30 days of delivery, unworn and in the original case with the cloth and packaging. Prescription and custom lenses are made to order and cannot be returned or exchanged unless we made them incorrectly. Returns are shipped by the customer to our warehouse in Surat, India, and return shipping is paid by the customer. See our Returns policy for the full process.
Warranty. One-year frame warranty and a six-month lens warranty covering manufacturing defects. Accidental damage and normal wear are not covered.
Lens care. Clean only with the supplied microfibre cloth. Our tints are absorptive through the full thickness of the lens material, so surface scratches do not change the transmission curve — but they do scatter light, which is worth avoiding. Do not use paper tissue, alcohol wipes or household cleaners.
Standards. Every lens carries 100% UV protection (UV400) and is tested against EN ISO 12312-1, ANSI Z80.3 and AS/NZS 1067.1. Spectrophotometer reports for each lens family are published on our research page.
Questions. Write to connect@sleepaxa.com and our optometry team answers directly.