Circadian Rhythm Lighting

The right wavelength for melanopsin secretion

Unlike the visual sensitivity of 555nm, the intrinsically photosensitive retinal ganglion cells (ipRGCs) perceive the light wavelength at 480nm  (typical) which affects the secretion of melanopsin, and melanopsin determines the circadian rhythm directly. A high-level radiance at 480nm will restrain the melanopsin secretion hence making us alert and focused, and a low-level radiance at 480nm is helpful for relaxation or pre-sleep.


Therefore, the right proportion and weight of centered 480nm (typical) radiance in the spectrum design are the key factors for circadian rhythm regulation.

Wavelength vs melanopsin secretion

Yujileds® Wlbeing technology, the well-designed spectral engineering for circadian rhythm stimulus

Wlbeing 2200K for melanopsin promotion

Wlbeing 2200K for melanopsin promotion

Wlbeing 4000K for melanopsin restraint

Wlbeing 4000K for melanopsin restraint

The 2200K is designed as warm white for relaxing lighting environment. To promote the melanopsin secretion, the spectrum is designed to isolate the ipRGCs sensitivity limited to 26% proportion.

The 4000K is designed as neutral white for focusing lighting environment. To restrain the melanopsin secretion, the spectrum is designed to fill the ipRGCs sensitivity sufficiently with up to 80% proportion.

Standard white colors with different circadian effect

The chromaticities of Yujileds® Wlbeing 2200K and 4000K are compliant with the standard white LED lighting (ANSI C78.377-2017), hence they provide the same visual effect as a general LED, but are significantly different when measuring with Melanopic / Photopic ratio (M/P ratio) and Melanopic DER (MDER).

standatd white colors woth dofferent circadian effect

High CRI for high-quality lighting

With our spectral engineering abilities and Yuji phosphor technology, Yujileds® Wlbeing 2200K and 4000K are designed to 85-95 CRI, that is to say, the Wlbeing LEDs satisfy both visual (color reproduction) and invisible (circadian stimulus) effects and can be widely used in high-end commercial lighting.

Yujileds® Super-warm technology, the ultimate option for melanopsin secretion

Beyond the standard white colors, we develop the Super-warm technology that has the M/P ratio down to 0.25 at 1800K. Compared to the nominal very-warm or amber LEDs, Yujileds® Super-warm achieves 95 CRI (typical) that can be used as white light but is greatly effective for the melanopsin secretion, which means the color quality will not be sacrificed when applying as the biological function lighting.


Product selection for circadian rhythm lighting