Resonansfärg

Resonansfärg, in Swedish, translates to resonance color. This term is used in physics and optics to describe a phenomenon where certain materials or objects appear to change color depending on the angle of observation or illumination. It is closely related to structural coloration and iridescence, where color is produced by the physical structure of a surface rather than by pigments.

The underlying principle of resonance color is the interference of light waves. When light strikes a surface with microscopic structures, such as thin films, gratings, or layered materials, the light waves are reflected and refracted. These reflected waves can interfere with each other. Depending on the wavelength of the light and the dimensions of the structure, constructive interference can enhance certain wavelengths (colors), while destructive interference can cancel out others.

This selective enhancement and cancellation of specific wavelengths leads to the perception of color. Because the path difference for the interfering light waves changes with the angle of incidence and observation, the color observed also changes. This is why objects exhibiting resonance color often display a shimmering or iridescent effect. Examples include the colors seen on soap bubbles, oil slicks on water, the wings of some insects, and the surface of certain opals. The precise term "resonansfärg" specifically emphasizes the wave interference aspect, highlighting the resonant amplification of particular wavelengths within the material's structure.