Reflectance

Reflectance is the measure of how much light or other radiation bounces off a surface instead of being absorbed or transmitted through it. It’s expressed as a percentage; higher reflectance means more light is reflected. For example, a mirror has high reflectance because it bounces most light back, while a black surface has low reflectance, absorbing most of the light. Reflectance helps us understand the appearance of objects, their color, and how they interact with light, which is important in fields like optics, astronomy, and material science.