Infrared sources refer to devices or mechanisms that emit infrared radiation, which is a type of electromagnetic radiation with longer wavelengths than visible light. These sources are commonly used in various applications such as night vision equipment, thermal imaging cameras, remote controls, and industrial heating systems. Infrared sources can be classified into two main categories: thermal sources, which rely on the heat generated by an object to emit infrared radiation, and non-thermal sources, which produce infrared radiation through electronic or chemical processes. Common types of infrared sources include incandescent lamps, light-emitting diodes (LEDs), and lasers. Each type of source has its own unique characteristics and advantages depending on the specific application requirements. Overall, infrared sources play a crucial role in enabling the detection, measurement, and manipulation of infrared radiation for a wide range of technological and scientific purposes.