مستشعر الطحالب الخضراء المزرقة

Blue-green algae are irradiated with excitation light of a specific wavelength, causing them to reach a higher energy state. When returning from this high-energy state to the ground state, they emit fluorescence at wavelengths longer than the excitation light. The intensity of this fluorescence is directly proportional to the concentration of blue-green algae in the water.