Scintillators are materials that emit light when they absorb ionizing radiation. They are commonly used in various applications, including medical imaging, radiation detection, and scientific research. When particles such as gamma rays or beta particles interact with a scintillator, the energy from the radiation excites the atoms in the material, causing them to release photons of light. These emitted light signals can be detected and measured using devices like photomultiplier tubes or photodiodes. Scintillators come in different forms, including crystals, liquids, and plastics, each with unique properties that make them suitable for specific uses in fields like nuclear physics and healthcare.