Circadian Rhythm Sample

The ALPHABET Human Centric Series featuring SUNlike® technology is redefining Circadian Rhythm LED by suppressing short wave blue LED that, studies show, can be harmful at night.

  • Patented SUNlike® technology duplicates the spectrum of the sun for interior lighting applications
  • Ideal spectrum for daytime light exposure without sacrificing desired color temperature Full CCT offering in 3000K, 3500K
  • CRI at 97 for rich color as seen outside
  • Each light engine is calibrated for consistent color point
  • Fills the “green gap” from traditional LED lighting
  • Spectral output designed to offer maximum protection from dangerous “Blue Light Hazard”
  • Follows Lighting Research Center at Rensselaer Polytechnic Institute spec guidelines for Circadian Lighting


The human circadian system is the body’s natural clock that affects critical functions including the production of testosterone, growth hormone, cortisol, and melatonin. These hormones have a direct influence on the body’s overall functionality in key areas including:

  • Sleep
  • Cognition
  • Performance
  • Alertness
  • Metabolism


Light is formally defined as optical radiation capable of providing visual sensation in humans. However, light also produces non-visual physiological responses that are unrelated to spatial patterns of light exposure. Scientists have discovered a photopigment called melanopsin in special photosensitive cells in the eye’s retina, in addition to rods and cones, which are part of the visual system. These cells, known as ipRGCs, form the main neural conduit to the suprachiasmatic nuclei (SCN) in the part of the brain where our circadian clock is located.

Circadian phototransduction is the process that converts light received by the three photoreceptors (rods, cones and ipRGCs) in the retina into electrical signals in the SCN. Both light and dark set the timing of the SCN, and disruption of this clock has been shown to negatively affect many health outcomes. The SCN control the release of melatonin, which is a hormone produced under conditions of darkness, normally at night. The spectral sensitivity of the SCN, as measured by acute melatonin suppression by light at night, peaks at approximately 460 nm.

ALPHABET Human Centric Lighting is RG-1 Eye Safety Rated which is the FIRST LED ever to receive the certification and is the lowest Risk possible. The governing body is International Commission on Illumination. What is CIE S009/2002 Eye and Skin Safety Certification?

Eye Safety Certification refers to the international standard the International Commission on Illumination adopted as standard (CIE S 009:2002) which defines the standard of LED illumination for the purpose of safety for the eyes and skin. The relevant standard is defined in IEC/EN 62471. Since the luminaire was widely used for LED, the assessment of risks to blue light became integral and the standard of IEC/EN 62471 began to apply to lighting and system using LED from September the 1st, 2009.

Risk Classification Table

Risk Group Risk
No Risk (Exempt) No photo-biological- risk
RG 1 (Low Risk) No photo-biological risk in normal daily life
RG 2 (Intermediate Risk) Doesn’t cause risk but feels unpleasant due to heat produced from bright light
RG 3 (High Risk) Dangerous even if a human is exposed to light for an instant