Valolähteiden
Valolähteiden is a term that generally refers to sources of light. These can be natural, such as the sun or stars, or artificial, such as light bulbs or lasers. The study of light sources is fundamental to understanding optics, illumination, and various technological applications.
Natural light sources are the original and most abundant sources of illumination in the universe. The sun
Artificial light sources have been developed by humans to provide illumination where natural light is insufficient