In this activity, students use a UV light-emitting diode pen to write secret messages and investigate a range of objects to see if or how they fluoresce.

By the end of this activity, students should be able to:

  • explain why an invisible dye fluoresces when UVA shines on it
  • use UV light to investigate objects to see if and how they fluoresce.

Download the Word file (see link below) for:

  • introduction/background notes
  • what you need
  • what to do.
    Published 29 July 2008, Updated 1 March 2013