Theory
Time allocation: 10 min.
Light
Light is the visible part o electromagnetic radiation. JIts frekvency ranges approximately between 3.9×10¹⁴ and 7.9×10¹⁴ Hz, which corresponds to wavelengths in a vacuum from 390 to 760 nm.
This range lies between ultraviolet (UV) and infrared (IR) radiation. A broader spectrum extending into UV and IR is also considered light in some scientific fields.
Light can be described in several ways:
- Photometrically: by luminance or luminous flux
- Colorimetrically: by color and spectrum
- By coherence and polarization
These properties determine how light behaves during reflection, refraction, passage through materials, interference, and diffraction.
Due to wave–particle duality, light exhibits the properties of both particles and waves.
Different light frequencies are perceived as different colors: from red (lowest frequency, longest wavelength) to violet (highest frequency, shortest wavelength).
On the shortwave side beyond visible light lies UV radiation, which affects human skin and causes tanning. On the opposite side is IR radiation – invisible to the human eye, but we feel its heat through skin receptors.
Visual Comfort
Light intensity is one of the key environmental factors in interior spaces. Adequate lighting positively affects our mood, productivity, and health. It helps create a pleasant atmosphere, improves focus, and enhances overall comfort.
Besides the amount of light, the color of light is also important. There are various shades even within “white” light:
- Warm white – resembles incandescent light, is cozy, and is used in living rooms, bedrooms, and children’s rooms. Less suitable for detailed visibility.
- Cool white – more neutral light that enhances contrast; ideal for kitchens, bathrooms, or toilets.
- Daylight white – bright with a slightly bluish tint, similar to daylight. Commonly used in well-lit workspaces.
RGB
RGB is a color model that uses three primary colors: red, green, and blue. For example, it is used for emissive color mixing in monitors and projectors. Unlike the CMYK model, RGB does not require external light – the device emits light on its own.
Typical wavelengths:
- Red: 700 nm
- Green: 546,1 nm
- Blue*: 435,8 nm
Colors are created by mixing the intensity of these components:
| R | G | B | Color |
|---|---|---|---|
| 0 | 0 | 0 | Black |
| 255 | 0 | 0 | Red |
| 0 | 255 | 0 | Green |
| 0 | 0 | 255 | Blue |
| 255 | 255 | 0 | Yellow |
| 255 | 0 | 255 | Magenta |
| 0 | 255 | 255 | Cyan |
| 255 | 255 | 255 | white |