How body react to light?
What is Circadian Rhythm?
Daylight Color Temperature and Circadian Rhythm
What is Blue Light?
ALFA Lighting Modeling and Simulation
3. ALTA INTEGRA
Sleep and circadian rhythms
We have 37 trillion cells in our body,
each with its own time clock.
For our bodies to sleep properly, it’s vital that
each cell is properly synchronised.
This is the function of something called
the suprachiasmatic nucleus (SCN), a tiny area of
the brain located within the hypothalamus.
The suprachiasmatic nucleus acts as our main
timeclock, entraining within our cells what is best
described as our body-clock or our ‘circadian
rhythm’.
6. ALTA INTEGRA
Light spectrum required for
Melatonin Suppression
Eye Retina
rods seeing low light
cones seeing in colour
Visual light response
Non-visual light responses
Ref: The University of Manchester
α-opic Illuminance sensitivity curve
7. ALTA INTEGRA
Melanopic Lighting responsible for
Melatonin Suppression
Blue Light 480 nm
Increase alertness
“Intense bursts of blue spectrum light
can temporarily increase alertness and
concentration in a similar way to a cup
of coffee… they act as a stimulant”.
The German standard DIN Spec 6760
also offers metrics for ‘biologically
effective’ lighting.
8. ALTA INTEGRA
by providing
appropriate-intensity
blue-spectrum light
during main daylight
hours and warmer
spectrum when the body
is gearing up or winding
down,
you create a suitable
environment for
melatonin suppression
(alertness) and cortisol
release to control body
temperature.
9. ALTA INTEGRA
Circadian Lighting System
artificial ‘sunrise to
sunset’
that travels through
illuminance levels and
colour spectrums from a
warm colour spectrum
(2,700K) to brighter,
cooler (6,500K and
upwards) and back again.
Ref: illumination engineering
society journal
10. ALTA INTEGRA
ALFA – the only tool capable of
predicting EML through physically
accurate, high spectral resolution
simulations – makes it easy to
calculate WELL Circadian Lighting
credits, and includes adjustable
targets.
Spectral raytracing allows ALFA to
predict the amount of light absorbed
by an observer’s non-visual
photoreceptors, given location and
direction of view. Since these
receptors absorb light using the
pigment melanopsin, the quantity is
referred to as
equivalent melanopic lux, or EML.
11. ALTA INTEGRA
Melanopic Lux (EML) is
already recognized by
international building
certification systems,
including the WELL Building
Standard.
The new WELL Building
Standard offers melanopic
illuminance values measured
vertically at face height as a
key to creating healthy
lighting.
The new WELL
Building Institute
standard offers
melanopic
illuminance values
measured
vertically at face
height as a key to
creating healthy
lighting.