What is the refractive index?

The refractive index is defined as a measure of how much light slows down when it passes through a medium compared to its speed in a vacuum. This property is crucial in fiber optics because it determines how light propagates within the fiber and how it interacts with different materials. When light enters a medium with a higher refractive index, its speed decreases, and the difference in refractive indices between materials can cause light to bend, or refract. Understanding the refractive index is essential for designing effective light-conducting systems, ensuring minimal signal loss and effective transmission over distances. Thus, this measure indicates the change in speed of light as it travels through various materials, making it fundamental to the principles of optics and fiber optics technology.