Dispersion staining
![These are the colored Becke` lines of a glass sphere that matches the refractive index of the mounting medium at a wavelength of 589 nanometers.](/Images/godic/202501/09/Dispersion_Staining_Becke_line1025.jpg")
![This is the color shown by a glass sphere that matches the refractive index of the mounting medium at a wavelength of 589 nanometers when using darkfield dispersion staining.](/Images/godic/202501/09/Dispersion_Staining_Darkfield1025.jpg")
![These are the colors shown by a glass sphere that matches the refractive index of the mounting medium at a wavelength of 589 nanometers when using phase contrast dispersion staining.](/Images/godic/202501/09/Dispersion_Staining_Phase_Contrast1025.jpg")
![](/Images/godic/202501/09/Loupe-binoculaire-p10308911025.jpg")
The optical properties of all liquid and solid materials change as a function of the wavelength of light used to measure them. This change as a function of wavelength is called the dispersion of the optical properties. The graph created by plotting the optical property of interest by the wavelength at which it is measured is called a dispersion curve.