Instructions

1. Drag the LED assigned to you to the LED socket found on the left of the left of the screen. The computer-generated spectrum emitted by the LED will appear on the top screen.
2. Click the Add Conduction Band button. A red rectangle that represents the conduction band for the LED should appear near the top of the energy scale.
3. Click on the Add Valence Band button. A faded-red rectangle that represents the valence band for the LED should now appear near the bottom of the energy scale.
4. The broad, orange vertical arrow represents the allowed transitions for electrons as they move from any energy in the conduction band to any energy level in the valence band. As these electrons make transitions, they emit energy in the form of light.
5. Place the cursor in the center of one of the bands. The band turns green and up-down arrows appear. You can now change the energies allowed in the band.
6. As you change the location or range in a band, you will see the spectrum. Now manipulate the location and range of both energy bands until the spectra described by the energy level matches.