What phenomenon does chromatic dispersion refer to?

Chromatic dispersion refers to the phenomenon where different wavelengths of light travel at different speeds through a medium, such as fiber optic cable. In the context of optical fibers, this occurs because the refractive index of the fiber material can vary with the wavelength of light. As a result, shorter wavelengths (like blue light) typically travel faster than longer wavelengths (like red light). This variation in speed can cause different colors of light to emerge at slightly different times when they propagate through the fiber, leading to a spreading of the signal over distance.

Understanding chromatic dispersion is crucial in fiber optic communications, as it can affect the bandwidth and overall performance of the system. By recognizing that different wavelengths do not travel uniformly, engineers can design systems and select materials that minimize these effects, thus ensuring clearer and more reliable data transmission over longer distances.