In the last few decades, chemists and physicists have made dramatic progress in understanding why materials have the colors they do. An apparently simple question leads to an amazing complexity and variety of processes.
Visible light is made up of waves, and can be sorted by wavelength into the colors of the spectrum.
Red light has the longest wavelengths and the lowest energy, violet the shortest wavelengths and highest energy. Physical Optics Formalisms Scattering One of the simplest mechanisms in physical optics is scattering. From the viewpoint of the sender, scattering randomizes light by reflecting it in myriad directions. From the standpoint of the viewer, it randomizes light by combining light from many sources. Several scattering mechanisms are evident in this sunset scene.