Optical characteristics refer to the properties of materials that affect how they interact with light. These properties include factors like refraction, reflection, and absorption, which determine how light passes through, bounces off, or is absorbed by a substance. For example, a clear glass window has high transparency, allowing most light to pass through, while a mirror reflects light, making it appear shiny. Different materials exhibit unique optical characteristics based on their composition and structure. For instance, prisms can bend light to create a spectrum of colors, while lenses can focus or disperse light rays. Understanding these characteristics is essential in fields like optics and photography.