Passive Optical Sensors are devices that detect light without emitting any signals themselves. They rely on natural light sources, such as the sun or artificial lighting, to gather information about their environment. These sensors can measure various parameters, including temperature, humidity, and even the presence of certain gases, by analyzing the light that interacts with different materials. These sensors are commonly used in applications like environmental monitoring, agriculture, and building management. By utilizing the existing light, Passive Optical Sensors are energy-efficient and can provide valuable data for decision-making processes without the need for active power sources.