Close-up view of a light emitting diode. The emissive semiconductor is the small rectangle in the center, attached to electrical leads and encased in a lens. At the end of the movie external lighting is turned off to highlight the glowing semiconductor.	GaAsP LEDs (center column of red, orange, yellow, green) viewed through a diffraction grating to produce first order diffraction to each side of the central original image. The grating is moved away from the viewer and back.
GaN LED lowered into liquid nitrogen.	Diffraction from an AlGaAs LED at room temperature (top) and when cooled in liquid nitrogen (bottom). Both first and second order diffraction is seen to each side of the original central image. As the cooled LED warms, its diffraction pattern again matches the reference.
Electrical conduction by movement of holes.	Illustration of diode behavior in an LED.
An energy band diagram for a pn-junction in an electric circuit.	Preparation of an LED by Metal Organic Chemical Vapor Deposition (MOCVD) an atomic layer at a time.

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