Coumarin 545 is widely used as a laser dye in the field of photonics and optoelectronics. It is particularly valued for its ability to emit bright green fluorescence when excited by ultraviolet or blue light, making it suitable for applications in dye lasers, where it helps generate tunable laser beams in the green spectral region. Additionally, it is employed in fluorescence microscopy and imaging techniques to label and track biological molecules or cellular structures due to its high quantum yield and photostability. In material science, it is utilized in the development of organic light-emitting diodes (OLEDs) and sensors, where its luminescent properties enhance device performance. Its compatibility with various solvents and matrices also makes it a versatile component in research and industrial applications.