luminesensenssi

Luminesenssi is a phenomenon where a substance emits light without producing significant heat. This is in contrast to incandescence, where light is produced by heating an object to a high temperature, such as a traditional light bulb filament. Luminescence occurs when a material absorbs energy from an external source, exciting its electrons to higher energy levels. As these electrons return to their ground state, they release the excess energy in the form of photons, which we perceive as light.

There are various types of luminescence, distinguished by the source of the excitation energy. Photoluminescence is triggered by the absorption of photons, as seen in fluorescent lights and glow-in-the-dark materials. Chemiluminescence is produced by a chemical reaction, with fireflies and some medical tests utilizing this principle. Bioluminescence is a specific form of chemiluminescence occurring in living organisms. Triboluminescence is generated by friction or mechanical stress on certain solids, like crushing sugar crystals. Electroluminescence involves the emission of light when an electric current passes through a material, a principle used in LEDs and OLED displays. Thermoluminescence is the emission of light by a substance that has previously absorbed energy, which is then released by heating. Cathodoluminescence is light produced when a material is struck by electrons, used in older cathode-ray tube televisions. The color and intensity of the emitted light depend on the specific material and the energy of the excitation source.