Dispersion demonstrator for eyewear lenses

The invention relates to an apparatus for comparatively demonstrating the optical properties of eyewear lenses, particularly dispersion. The apparatus includes an illumination source that provides output of shorter wavelength visible light and longer wavelength visible light, a target that creates an image on the light path, a test lens made of eyewear lens material that is illuminated by the light path from the target, and a detector that displays the image acted upon and transmitted through the test lens. The test lens can be interchangeably replaced with another test lens, for comparison of each lens' optical properties. Alternate configurations include multiple light paths, for simultaneous viewing of images through different test lenses.