The scientific name for the separation of light into its different colors when it passes through a prism is called "dispersion." Dispersion occurs because the prism material's refractive index varies with the wavelength (or color) of light, causing different colors to bend by different amounts as they pass through the prism. This bending, or refraction, causes the white light to spread out into its constituent spectrum of colors ranging from red to violet. The phenomenon of dispersion was first extensively studied by Sir Isaac Newton using prisms, leading to the understanding that white light is composed of various colors. This effect is used in scientific instruments such as spectroscopes to analyze light spectra.