Understand the light
To understand light, we need to analyze the functioning of our corneas and retinas.
During the day, our eyes perceive the electromagnetic radiation of the sun measured in wavelengths between 380 and 780 nanometers.
This perception occurs through the cornea that sends the message to our retina, which is essentially composed of nerve cells called « cones »
In the absence of the sun, other nerve cells come into play, the « rods », which give us night vision in grey.
In opposition to cats, these rods are less numerous and less efficient, hence this important feeling of dark.
The Blue Light
We are regularly warned against the harmful effects of blue light !
The wavelength of blue light from our (screens or devices) (smartphone, tablet, computer, etc.) is between 400 and 450 nanometers and is harmful to our retina and crystalline lens.
In exchange, the blue light from our sun is between 480 and 500 nanometers, stimulating the production of melatonin which is very beneficial to our circadian rhythms.

Color perception in nanometers
« Les Lumières de l’Agdal » studies the effects of light
Whether it is to promote concentration at a workstation or a classroom, to soothe and relax in a reading room, for safety in public spaces, in order to provoke the desire to buy or arouse emotion by contemplating a work of art, a lighting designed to respond to each situation will bring you serenity.
For this to be possible different parameters and coordinates must be studied
- Photometric criteria : The amount of light emitted (Luminous flux), its density (illumination), the light emitted in one direction (luminous intensity), the sensation of brightness (luminance),
- The quality of the lighting : The color of the light (color temperature in Kelvins), a good color rendering (color rendering index IRC), uniformity, reduction of glare (Unified Glare Rating, UGR), shadow and light balance, the level of illumination, intensity variation and avoidance of reflections.
- Aesthetics : Integration
- Environmental factor : consumption, life luminaire, energy efficiency
- Lighting techniques : Direct, indirect and direct-indirect
Mastering the LED
Light has a beneficial effect on health at the time and in time. Its effects are functional, biological and emotional. It is therefore essential for our well-being that light be adapted to the circumstances. The destination of the place and the different areas of the place, the time of day and the audience to which one addresses.
Lighting design will have a direct impact on your health, mood, environment and finances. The specialists at LLDA are here to help you create the atmosphere that will foster your quest for excellence.