licht.wissen No. 01 "Lighting with Artificial Light"

licht.wissen 01
Lighting with Artificial Light
02 03 04
From natural light to light when we need it
Light is life – and essential for people, animals and plants. For a long time, before people were able to use
artificial light, natural daylight was the only light available. Modern lighting concepts combine both light sources –
for our improved well-being and health.
We use our eyes for orientation – our environment
is the world we see around us. We
take in more than 80 percent of all information
through our eyes; they are our most
important sensory organ. Without light, this
would be impossible: light is the medium
that makes visual perception possible.
Light is quality of life
Insufficient light or darkness prevent good
vision: we feel unsafe and lose our bearings.
Only with good lighting do we feel
safe.
And so light not only enables us to see, it
also affects our mood and sense of wellbeing.
Moreover, since the turn of the millennium
we know that natural daylight and
how it changes during the day and the year
also affects our hormone levels and controls
our circadian rhythm. The right lighting
thus contributes to our health and our
quality of life.
In the beginning there was fire...
For a long time the sun was humanity’s only
source of light. About 300,000 years ago
man began using fire as a source of heat
and light. Glowing flames allowed people
to live in caves which the rays of the sun
could never penetrate. The cave drawings
in Altamira, for example, can only have
been created some 15,000 years ago in
artificial light. Light from camp fires, kindling
torches and oil and tallow lamps was a
significant achievement in the everyday life
of prehistoric man.
But light was not only created in enclosed
spaces: the Lighthouse of Alexandria was
built in around 260 BC, and there is evidence
of “lights in the streets” in Antioch,
i.e. of street lighting, in 378 AD.
From a very early stage, people began to
design ornamental yet functional holders of
the precious light-giving flame. However,
there were no significant improvements in
the liquid-fuel lamps which were used for
thousands of years until 1783 when Aimé
Argand invented the central burner.
In that same year a technique discovered
by Minckelaers was used to obtain “coal
gas” for gas lanterns. Almost at the same
time, the first experiments were being conducted
with electric arc lamps. However,
these only gained practical significance in
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