LEDs and Photons Workshop
Presented by the Center
for Nanoscale Systems Institute for Physics Teachers (CIPT)
Saturday, March 27, 2004
|8:30-9:00 a.m.||Registration and Continental Breakfast|
|Welcome and Introduction|
|9:10-10:10 a.m.||Prof. George Malliaras, "Organic light emitting devices"|
|10:30-11:30 a.m.||Lab Tour|
|12:45-1:45 p.m.||Hands-on Activity 1|
|2:00-3:00 p.m.||Hands-on Activity 2|
|3:15-3:30 p.m.||Closing and Evaluations|
"The Phantastic Photon" - Different colors of light are directly related to the energy and wavelength of the photons which compose that light. Students investigate these relationships by shining colored light from super-bright LEDs onto fluorescent paint and glow-in-the-dark tape and observing the emitted light by eye and with a handheld spectrometer. Students order the colors of light from highest to lowest energy and determine the role of light intensity in exciting the energy level transitions involved in fluorescence.
- "Light Emitting Diodes" (LED) -Using super-bight light-emitting diodes students investigate the conversion of electrical energy into light. Measuring and comparing the energy lost by each electron with the frequency of the emitted light for several LED colors allows students to determine Plank's constant, a fundamental number in quantum mechanics. Students also investigate other properties of LEDs and learn why they are increasingly used as indicators and light sources.