Melagen® Definitions

Circadian Rhythms

Circadian rhythms are physical, mental and behavoural changes that follow an approximate 24 hour cycle.

Colour Temperature

Colour Temperature or CCT generally measures the “warmth” or “coolness” of the appearance of a light source; measured in degrees Kelvin (K). CCT is not the real operating temperature of a lamp. It is the temperature to which you would have to heat a black body to make it glow with the same colour.


A Colour Rendering Index is the quantative measure of the ability of a light source to reveal the colours of various objects in comparison to an ideal source / daylight.

Electromagnetic Spectrum

The electromagnetic (EM) spectrum is the range of all types of EM radiation. Radiation is energy that travels and spreads out as it goes – the visible light that comes from a light source and the radio waves that come from a radio station are two types of electromagnetic radiation.


Light arriving at a surface, expressed in lumens per unit area; 1 lumen per square meter equals 1 lux.


intrinsically photo sensitive retinal ganglion cells found in the human eye.


A unit of illuminance equal to 1 lumen per square meter.

M/P Ratio (Melanopic / Photopic ratio)

This is a measurement that demonstrates a light source’s biological impact on sleep and alertness. The M/P ratio is available for all MelaGen® products.

The lower the decimal (.35) the better the light is for sleep and inducing calmness. The higher the decimal (.9) the better that light is at suppressing melatonin and increasing alertness.

How to apply the M/P ratio.
Obtain the M/P ratio for a specific MelaGen® product and apply the following:
Photopic Lux* x M/P ratio = Melanopic Lux

COMO Blue with M/P ratio of 0.9
400 photopic lux at eye level (vertical light) x 0.9 = 360 Melanopic Lux

MelaGen® Blue

A blue enriched LED source with outstanding high CRI and proven alerting properties and 4000k CCT.

MelaGen® ReFresh

A blue depleted LED light source with a warm light of 2200k CCT, similar to candlelight.

MelaGen® ReGen

is a combination of MelaGen® Blue and MelaGen® ReFresh LED light source in a single light fitting. Light scheduling in a permanently occupied space for example a bedroom, would transition from MelaGen® Blue to MelaGen® ReFresh. This transition from blue enriched to blue depleted can be programmed to enhance the human circadian cycle.

Melanopic Lux

Melanopic Lux is a term used to describe the measure of light which activates melanopsin (ipRGCs) in the human eye. This is primarily blue light at 480/490nm, like a blue sky.


A photopigment which is sensitive to blue light (480 –  490nm) and is found in the ipRGC’s of the human eye.


The chemical produced by the Pineal gland that helps us sleep.

Nanometre (nm)

A nanometre or nanometer is a unit of length in the metric system, equal to one billionth of a metre.


is the circadian controller also called the “master clock”. It regulates the release of melatonin by the pineal gland.

Spectral Power Distribution

A spectral power distribution (SPD) is a graph of the energy levels of a light source through a range of wavelengths of light. The spectral power distribution is the true fingerprint of a light source, as it is the key to how the light source renders colours.

Visual Spectrum

The visible light spectrum is the segment of the electromagnetic spectrum that the human eye can view, Typically, the human eye can detect wavelengths from 380 to 700 nanometres.