Optical characteristics refer to the properties of materials that determine how they interact with light. These properties include aspects such as refraction, reflection, and absorption, which influence how light is transmitted, bent, or absorbed by different substances. Understanding these characteristics is crucial in fields like optics, photography, and materials science. The study of optical characteristics helps in designing lenses, glasses, and other optical devices. For instance, the refractive index of a material indicates how much light slows down when entering it, affecting how images are focused. This knowledge is essential for creating effective optical systems in various applications.