What is the name of an optical element that refracts light and separates it into different colors?

The optical element that refracts light and separates it into different colors is called a prism. A prism works on the principle of refraction, which occurs when light passes through materials of different densities. When white light enters a prism, it is bent at different angles depending on the wavelength of light, as each color of light is refracted by a different amount. This results in a spectrum of colors ranging from red to violet, commonly seen in phenomena such as rainbows.

Lenses also refract light, but their primary function is to focus light rather than separate it into colors. Mirrors reflect light, which does not lead to the separation of colors. Filters are designed to block certain wavelengths of light while allowing others to pass through, but they do not separate light into its constituent colors. Therefore, the prism is specifically recognized for its ability to disperse light into a spectrum, making it the correct answer.