Evening · 21:42 · Indoor
Melanopsin links light to circadian timing.
Melanopsin is a photopigment in the human retina. It signals the suprachiasmatic nucleus (the brain’s master clock), which then shapes the release of hormones, including melatonin and cortisol.
Peak activation occurs near 480nm and decline begins above 550nm. Small percentages still matter over hours of cumulative exposure, especially when bright indoor light and screens continue late into the evening.
Melanopsin senses daylight wavelengths.
Intrinsically photosensitive ganglion cells respond strongest to blue and green light, sending the daytime signal upstream.
The signal reaches the SCN.
The suprachiasmatic nucleus reads the light pattern as a cue for time of day, and adjusts downstream rhythms to match.
Melatonin and cortisol shift.
Onset and amplitude of these hormones move with the light signal, which is why evening exposure can delay the start of natural melatonin release.
Where most blue-blocking stops. CytoSleep keeps going.
Standard blue-blockers typically extend to about 540nm. CytoSleep extends the cutoff further, holding a virtually flat transmission profile all the way up to 580nm. That covers the green and yellow-green range where melanopsin is still meaningfully sensitive.
Screens still look red and amber rather than washed-out, but the wavelengths that most strongly tell your brain “it’s daytime” are removed.
Peak near 480nm. Sensitivity remains meaningful across the blue and green range.
Measured under the same desk light.
Spectrometer readings of the baseline desk light, a typical competitor lens, and CytoSleep, plotted across the same 380–780nm window so the lens behavior reads at a glance.
Baseline desk light, no glasses
Visible energy across blue, green, yellow, red.
A standard blue-blocking lens
Substantial transmission remains in the green & yellow-green band.
Broad-spectrum blocking through 580nm
High transmission preserved in the 610–630nm range.
Pill or filter.
This isn't a dismissal of melatonin. It separates an external hormone approach from an optical filtering approach for bright evenings and late screens.
Melatonin pill
- Mechanism
- Adds melatonin from outside the body.
- Best fit
- Jet lag, shift work, or specific clinical guidance.
- Tradeoffs
- Dose timing, product variability, and possible morning heaviness.
CytoSleep glasses
- Mechanism
- Filters the wavelengths measured to activate melanopsin during evening exposure.
- Best fit
- The final 1–3 hours before bed, around screens and bright rooms.
- Tradeoffs
- Adherence is sometimes challenging, but very much worth it.
Broad-spectrum red-lens glasses for evening light.
Designed for late-evening screens and bright indoor rooms. Batch-tested against the claimed wavelength blocking. Acetate frame, lightweight, indefinite after-purchase support.
CytoSleep glasses are not intended as a substitute for sunglasses, and do not serve as eye-protection of any kind.