Notice that on the left of the screen is an illustration of
6 different LEDs and a virtual circuit apparatus to explore the
properties of LEDs as voltage on them changes. On the right of
the screen are the two blocks of material that make up the LED
chip with an energy scale and output spectrum illustrated below
the blocks.
In this program, we can:
- Select an LED and drag it to the power supply (LED socket).
- Create an energy band diagram for each of the two semiconductor
blocks that make up each LED.
- Add donors or acceptors to each semiconductor block with
a click of the mouse inside each block and thus create the LED
chip.
- Control the voltage applied across the LED by moving the
slider.
When the voltage is appropriate, transitions (represented
by a vertical arrow) will occur and light will be emitted. A
spectrum will appear below the energy scale.