fluoresenssisäteily

Fluoresenssisäteily, commonly known as fluorescence, is a type of photoluminescence. It is the emission of light by a substance that has absorbed light or other electromagnetic radiation. This absorbed energy causes electrons in the substance to move to a higher energy level. As these electrons return to their ground state, they release energy in the form of photons, which we observe as light. The emitted light typically has a longer wavelength and lower energy than the absorbed radiation.

The process is rapid, occurring within nanoseconds of excitation. This distinguishes fluorescence from phosphorescence, where the emission of light can persist for much longer periods after the excitation source is removed. Many organic and inorganic materials exhibit fluorescence, including certain minerals, dyes, and biological molecules. The specific wavelengths of light absorbed and emitted are characteristic of the fluorescent substance.

Fluorescence has numerous practical applications. In science, it is used in microscopy to visualize specific cellular structures or molecules. In analytical chemistry, it serves as a sensitive detection method. Fluorescence is also employed in various industries, such as in fluorescent lighting, security inks, and diagnostic tests. The phenomenon is dependent on factors like the chemical structure of the material, the wavelength of excitation light, and the surrounding environment.