In this previously divulgated paper [1] we demonstrate that the light diffracted by a simple compact disc can be used to generate images with interesting basic attributes. We compare this attributes with the ones obtained with refractive elements. A compact disc acts as an axicon that generates a diffraction-free beam and, because the focused position of the image depends on the wavelength of the diffracted light, thus it can be useful as a spectral filter. The experiments are of easy reproduction, allowing the understanding of images that the students observe daily at school or at home.
optics; imaging; difraction; axicon; white-light imaging; diffractive optics; refractive optics; simple optics experiments