Lighting Basics
Light into the dark
René Moser
10. April 2018
René Moser

Light has always attracted people. Its actual effect remains unknown to science. One thing is clear: every life form on earth needs it. Light is a true multitalent. We have put together a compact summary of what it can do and what happens when you press a light switch.

Giver of life and more

Light is important for human, animal and plant life. Without light, all life would be threatened with extinction. Apart from this, light is important in all areas of life: at the workplace, in the living room or in public places: light – or, more precisely, lighting – presents often as a necessary prerequisite for work, and creates joy through exciting design.

EGLO has know-how in the area of lighting technology to create the right lighting: From light propagation to wavelength, from colour spectrum to colour reproduction.

Let us go ride the waves

Researchers are still not in agreement on whether light is made up of electromagnetic particles or of waves. Speaking of waves, you start thinking of the sea? That's not all that inaccurate! Light moves like a surfer elegantly rides on the waves. No water means no waves – this is different for light. When light spreads, an electromagnetic field is produced – at least according to the theory of light particles. The electromagnetic field is produced by collisions with light – particles are broken free by the impact. This property is important for solar power generators.


Casting a shadow at light speed

Light spreads in a straight line and always originates in the light source. This may be the sun or the lamp of your luminaire. This light source produces many individual rays of light that will hit different objects: mountains, the closest house, yourself or a parasol. All of these things stop the path of the imagined light rays, which causes every object to cast a shadow when exposed to light.

Light is a true speed king: at an unimaginable 300,000 km/s, it spreads much faster than any wave in the sea. In contrast to the sea's waves, we cannot see every wave made by light: broad, drawn-out waves and narrow waves close to each other are invisible to us. The human eye is only able to recognise a specific range of wavelengths that can be processed by the brain. More technically speaking: all light waves with a wavelength between 380 and 700 nanometers are visible to us.


Wonderful colours

Depending on wavelength, our eye will interpret different colours: low wavelengths lead us to perceive colours such as violet, blue and green. High wavelengths describe red, orange and yellow.


The colour in which we see objects depends on how much and, most of all, which light is reflected or absorbed. The red stop sign at the crossroads mostly reflects the red shares of the light to alert us that we need to stop. Other light colours are mostly absorbed. When we shine ultraviolet light on the stop sign, we will not see much red anymore: the light source must contain radiation shares of the respective colour, too. Therefore, luminaires and lamps should be chosen with the right colour temperature for creating a pleasant mood in the room.

René Moser
René Moser
I have been working for EGLO in online marketing since December 2017.
I am responsible for Content & Publishing Management as well as social media.

You might also be interested in

Bath & Mirror Luminaires
The women whisperer - Colour Rendering Index
12. October 2018
Vanessa Koch
A delicate hint of rosé on the cheeks, perfect contours and a breath-taking look. I didn't see all this when I looked at myself in the mirror of the elevator. With the feeling of being at the mercy I took the few steps to our open-plan office. There the partly questioning, partly unbelieving looks stabbed me in the back. I began to think: "Is that really necessary?"
Read more
Light off for halogen lamps
17. September 2018
René Moser
September makes everything new. At least when it comes to the final step towards banning halogen lamps. For several years now, the EU has been successfully phasing out electricity guzzlers by means of legislation. At just under 60, the halogen lamps has reached retirement age and is leaving the stage. We have summarised for you here exactly how this departure looks like and who shines as a new star in the lamp sky.
Read more
Garden Lighting
Sustainable, practical, good – solar luminaires
13. September 2018
Anna Zimmermann
You like to grill? Then you spend a large part of the summer on your terrace or balcony. When the last sunrays flash through the treetops at the end of the day, twilight falls over the landscape. It's only a few minutes till nightfall. Then comes their big performance: We are talking about our solar luminaires. Why these are so practical and what this investment has to do with sustainability, we show you here.
Read more