Acieon Labs
The science

From the photon to the circadian clock

Acieon Labs studies how light reaches the human eye and the circadian system. The science below is presented in three layers: a plain summary, a technical explanation, and the primary source that supports it. Every claim is citable.

Last updated: June 2026

460 nmMelatonin suppression peak480 nmMelanopsin peak380440480520560620680720Visible spectrumWavelength (nm)
The visible spectrum, 380 to 720 nm. The melanopsin response peaks near 480 nm and the melatonin suppression action spectrum peaks near 460 nm. Sources: Berson 2002, Brainard 2001, Lucas 2014.
01

The visible spectrum and the eye

In plain terms

The light we see spans wavelengths from roughly 380 to 720 nanometres. Different parts of this spectrum affect vision and the body in different ways.

Technical

Across the visible range, short-wavelength light carries the most energy and has the strongest non-visual biological effect. Photobiological eyewear works by shaping how much light of each wavelength reaches the retina, a measured transmission profile rather than a single cut-off.

Source

Lucas RJ et al. (2014). Trends in Neurosciences 37(1):1 to 9. Measuring and using light in the melanopsin age.

02

ipRGCs and melanopsin

In plain terms

Beyond the rods and cones that let us see, the retina has special cells called intrinsically photosensitive retinal ganglion cells. They respond to light directly and help set the body clock.

Technical

Intrinsically photosensitive retinal ganglion cells express the photopigment melanopsin, whose intrinsic light response peaks in the short-wavelength region near 480 nanometres. They drive non-image-forming responses to light rather than forming an image.

Source

Provencio I et al. (2000). Identification of melanopsin in the human retina. Berson DM, Dunn FA, Takao M (2002). Science 295:1070 to 1073.

03

The suprachiasmatic nucleus and circadian phase

In plain terms

Light signals from these cells travel to a small region of the brain that acts as the master clock, telling the body when it is day and when it is night.

Technical

Through the retinohypothalamic tract, intrinsically photosensitive retinal ganglion cells signal the suprachiasmatic nucleus. Evening short-wavelength light reaching this pathway can suppress melatonin and delay circadian phase.

Source

Hattar S et al. (2002). Science 295:1065 to 1070. Brainard GC et al. (2001). Journal of Neuroscience 21(16):6405 to 6412.

04

Selective spectral filtration

In plain terms

The goal is not to block all light, but to filter selectively, so that helpful daytime light is preserved while the wavelengths that disturb the body clock at the wrong hour are attenuated.

Technical

Acieon Labs designs wavelength-selective ophthalmic lenses, characterised by their transmission profile. Selective filtration aims to attenuate selected bands relevant to circadian and photophobic load while preserving photopic luminance and colour balance.

Source

CIE S 026/E:2018. CIE system for metrology of optical radiation for ipRGC-influenced responses to light.

Melanopsin sensitivity

The response peaks near 480 nm

Melanopsin, the photopigment in intrinsically photosensitive retinal ganglion cells, responds most strongly to short-wavelength light near 480 nanometres. This is why evening short-wavelength light has a strong non-visual effect.

480 nm380460480560640720Relative sensitivityWavelength (nm)
Melanopsin sensitivity peaks near 480 nm. Illustrative curve about the sourced peak. Sources: Berson 2002, Lucas 2014.
Non-visual pathway

How light reaches the body clock

01

Light near 480 nm

Short-wavelength light enters the eye

02

ipRGC and melanopsin

Retinal cells respond directly to light

03

Suprachiasmatic nucleus

Reached via the retinohypothalamic tract

04

Melatonin and circadian phase

Non-visual response is set

Primary literature

References

  1. Hattar S, Liao H, Takao M, Berson DM, Yau K (2002). Science 295:1065 to 1070. Melanopsin-containing retinal ganglion cells project to the suprachiasmatic nucleus.
  2. Berson DM, Dunn FA, Takao M (2002). Science 295:1070 to 1073. Phototransduction by retinal ganglion cells that set the circadian clock. Intrinsic response peaks near 480 nm.
  3. Provencio I et al. (2000). Identification of melanopsin in the human retina.
  4. Brainard GC et al. (2001). Journal of Neuroscience 21(16):6405 to 6412. Action spectrum for melatonin regulation in humans, peak sensitivity in the 446 to 477 nm region.
  5. Thapan K, Arendt J, Skene DJ (2001). Journal of Physiology 535(1):261 to 267. Human melatonin suppression action spectrum, peak near 459 to 460 nm.
  6. Lucas RJ et al. (2014). Trends in Neurosciences 37(1):1 to 9. Measuring and using light in the melanopsin age. Melanopsin sensitivity standardised at 480 nm.
  7. CIE S 026/E:2018. CIE system for metrology of optical radiation for ipRGC-influenced responses to light. Defines melanopic equivalent daylight illuminance.
From science to IP

See how the science becomes intellectual property

The patent register and the published research corpus build on this science.

Patents and InnovationPublications