In this case a prism composed of glass with a wavelength-dependent refractive index disperses a beam of light into a spectral caustic.
(a prism; composed; of glass with a wavelength-dependent refractive index) (a prism composed of glass with a wavelength-dependent refractive index; disperses; a beam of light into a spectral caustic; L:In this case)
a prism a prism composed of glass with a wavelength-dependent refractive index
composed disperses
of glass with a wavelength-dependent refractive index
a beam of light into a spectral caustic L:In this case