A fluorometer is an analytical instrument used to measure the fluorescence of a sample. Fluorescence occurs when a substance absorbs light at one wavelength and then emits light at a longer wavelength. This property is utilized in various fields, including biology, chemistry, and environmental science, to analyze the presence and concentration of specific compounds. Fluorometers can be used to detect chlorophyll in water samples, monitor pollutants in the environment, or study biomolecules in research. They are valued for their sensitivity and ability to provide real-time data, making them essential tools in both laboratory and field settings.