THE LIGHT SPECTRUM
About daylight and LEDs
Why should we try to adapt our artificial lighting to the natural light spectrum?
Quite simply because our biorhythm, our internal clock and our overall well-being depend on this cycle. That is why it is important to pay attention to it.
THE ENTIRE COLOR SPECTRUM
Of the entire electromagnetic spectrum, only a relatively small range can be perceived by us as visible light. Our eyes detect visible wavelengths ranging from blue (approx. 400 nanometres) to red (approx. 700 nm). Together, these wavelengths, in the same proportions, produce the ‘white’ light that we see. It appears neutral to us, even though it is a combination of different colors. If light passes through a prism, water or an optical grating, for example, it is broken down into its spectral components. Only then do we recognise the different colors. The best example is the rainbow.
THE DAYLIGHT SPECTRUM
Natural daylight covers the entire visible spectrum. GREEN is the most prominent color within this spectrum. This also explains why the human eye has the greatest number of receptors for green light. We perceive green as natural, soothing and pleasant. We do not have to make any effort to perceive it.
LIGHT SOURCES AND THEIR LIGHT SPECTRUM
- INCANDESCENT BULBS
The classic incandescent bulb with its tungsten filament emits a warm, cosy light, reminiscent of the light spectrum of a sunset. Red, orange and yellow are more prominent than blue and green. No wonder we feel so at ease in this atmosphere. Incidentally, the light from an incandescent bulb also has an excellent color rendering index (CRI).
- FLUORESCENT TUBES AND ENERGY-SAVING LIGHT SOURCES
Fluorescent and energy-saving light sources, which also include gas-discharge lamps, often produce a very uneven light spectrum. This is simply down to the technology and the wide variety of phosphors and gases used. The peaks in the spectrum are often in the green or blue range, which is why these light sources are often perceived as giving off a cool light and are sometimes even described as ‘unpleasant’.
However, these light sources have been phased out following the entry into force of the EU regulation, as, in addition to producing unattractive light, they contained toxic substances. Furthermore, they consumed an unnecessary amount of electricity and were difficult to dispose of.
- LED light sources and their light spectrum
First of all: there is NO LED that emits pure white light. Two techniques are used to make an LED appear to emit white light.
- The RGB mix – red, green and blue diodes are mixed in various ratios to produce white light. Unfortunately, this usually results in an uneven, fragmented light spectrum, often with peaks in the blue range. And that is precisely what we actually want to avoid.
- Blue LED light is converted into a yellower/warmer light by various phosphor layers. The most commonly used phosphor is a yellow phosphor layer made from various phosphor mixtures. Phosphors are ceramic-like, inorganic compounds of rare earth elements. These include, for example, phosphate, silicate and oxonitrido-aluminium silicate. The composition and quality of this layer are what determine the color temperature and light spectrum of an LED light source.
The second type is very commonly found in modern filament LED light sources, which now come very close to the good old incandescent bulbs in terms of color and light quality. However, they are much more economical and efficient.
The light spectrum of our artificial lighting has a major influence on our daily lives. That is why we should pay close attention to good, high-quality light sources. A uniform light spectrum is an indication of the high quality of an LED light source. Thanks to their warm color of light, SEGULA LED light sources have a uniform spectrum with a low blue component and minimal peaks. This creates an incomparably pleasant lighting ambience and atmosphere. "Comfort Zone Deluxe" with the right light!
