Abstract

The electromagnetic spectrum is usually classified by its wavelength and the energy levels associated with it. Teaching these relations to kids without an exploration activity could be a real challenge. On this subject, we have designed a lesson using lasers, diffractions gratings, and photoluminescent materials. This lesson includes activities that allow introducing different optics and photonics concepts. The warm-up activities are to learn the monochromatic nature of lasers, show how diffractions gratings work and explain the concepts of phosphorescence and fluorescence. All this knowledge is combined to see the different energy levels associated with three colors of lasers: red, green and violet. Using different lasers the kids explore which ones activate the fluorescence or phosphoresce effects in the materials provided and, finally, they examine these effects using diffraction gratings. The diffraction gratings allow exploring how a laser can cause fluorescence and how the light emitted by this phenomenon is related to the color of the laser and other colors with less energetic wavelengths. Also, the different lasers are used to analyze which one can cause phosphoresce over materials and comparing the violet lasers with the UV light. In the end, the conclusion is based on the law of conservation of energy.

© 2019 SPIE, ICO, IEEE, OSA