Ra Optics vs Swanwick vs TrueDark vs Bon Charge, tested for blue transmission percentage at specific wavelengths.
Ra Optics Dusk Lens (evening)
Published transmission spectra showing ~0% transmission below 550 nm. That is the band where melanopsin responds. A clear lens that only attenuates short wavelengths is not adequate for post-sunset use; the red-tinted lens is what actually blocks 450-500 nm.
Check price · Amazon- 01 ·Our pick, evening
Ra Optics Dusk Lens
Red-amber evening lens with published transmission data. Cuts essentially all light below ~550 nm. Worn 2-3 hours before target bedtime, preserves evening melatonin onset.
Check price · Amazon - 02 ·Strong alt
Bon Charge Sleep+ (evening)
Red-tint evening lens in the same category as Ra Optics Dusk. Published third-party transmission data [VERIFY batch]. Broader frame selection. Direct competitor in the serious-evening-blocker segment.
Check price · Amazon - 03 ·Clinical-grade
TrueDark Twilights (evening)
Dark red 'Twilights' lens was the category pioneer. Very low transmission across the short-wavelength spectrum. Limited frame styles; premium price. The pick for readers prioritizing maximum blocking over aesthetics.
Check price · Amazon - 04 ·Evening value
Swanwick Classic Night Swannies
Orange-tinted evening lens. Less aggressive than red-tint options; transmits a bit more in the 500-550 nm range. Lower price point, good frame selection. Adequate for 90% of evening use cases.
Check price · Amazon - 05 ·Daytime anti-glare
Ra Optics Daylight Lens
Clear-to-light-yellow lens for daytime screen use. Filters some short-wavelength flicker without blocking the morning circadian signal. Do not substitute for the Dusk lens in the evening.
Check price · Amazon - 06 ·Daytime alt
Swanwick Daywalker
Swanwick's daytime clear lens. Same use case as Ra Optics Daylight. Fine for daytime screen comfort, wrong tool for evening circadian protection.
Check price · Amazon - 07 ·Daytime alt
Bon Charge DayMax
Clear lens with mild short-wavelength attenuation for daytime. Aesthetic frames; Bon Charge's design advantage over clinical-looking competitors. Evening use still requires Sleep+.
Check price · Amazon - 08 ·Daytime
TrueDark Daylights
Light yellow-tint daytime lens. Useful for long-duration screen work. Not an evening lens.
Check price · Amazon - 09 ·Lifestyle blue-light
Felix Gray Jemison (lifestyle)
Stylish, very mild blue attenuation. Essentially cosmetic for circadian purposes; it will not preserve evening melatonin. Good frames; wrong product if circadian protection is the goal.
Check price · Amazon - 10 ·Gaming-oriented
Gunnar Optiks
Gaming category: amber tint, moderate blue attenuation. Between Felix Gray and serious evening lenses. Better for extended gaming sessions than circadian use.
Check price · Amazon
Questions logged on this protocol
Do blue-blockers actually preserve melatonin?
The red-tint evening lenses, yes. Burkhart & Phelps 2009 (Chronobiol Int) and Shechter et al. 2018 (J Psychiatr Res) showed amber/red blue-blockers worn 2-3 hours before bedtime preserved dim-light melatonin onset relative to controls. Effect sizes are meaningful for evening screen users. Clear and light-yellow 'computer glasses' show minimal circadian effect; they are eye-comfort products, not circadian products.
What wavelength do they need to block?
Melanopsin, the circadian photoreceptor, peaks at ~480 nm, with the functional range ~440-500 nm. A genuine evening lens should block nearly all transmission below ~500 nm, ideally below ~550 nm. The red-amber appearance is diagnostic: a clear or light yellow lens is not doing enough.
When should I put them on?
2-3 hours before target bedtime. Cajochen et al. 2011 (J Appl Physiol) showed evening light suppresses melatonin within ~30 minutes of exposure, so the window to prevent that suppression is the pre-DLMO period. For a 23:00 bedtime, that means 20:00-21:00 put-on time. Keep them on until you turn the lights off.
Can I just use a phone night mode?
Partially. iOS Night Shift and Android equivalent warm the display color temperature, reducing blue output from the screen. They do nothing for overhead lights, which typically contribute more photon flux than the phone. Night mode is a useful layer; it does not replace ambient light hygiene or blue-blockers if you are in a bright-lit room.
Do they make you feel sleepy?
Not directly. They prevent melatonin suppression, which preserves the natural buildup of sleep pressure in the evening. Many users describe 'feeling sleepier at night' after a few weeks; that is the absence of iatrogenic alertness, not a sedative effect. If you feel acutely drowsy when you put them on, check for a room that is actually dimmer than you realized.
Can I wear them while working at night shift?
Generally no. Night-shift workers need alertness during shift. Smith & Eastman 2008 (Sleep Med Clin) recommend blue-blockers on the commute home (to block morning light that would otherwise prevent daytime sleep) rather than during the shift. Use them as a one-way valve into the daytime sleep window, not during active work.
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