  It is widely believed that the generation of high speed optical signals is
not the job for an LED. However this work is done to show that there are
techniques which can be used to produce nanosecond square pulses from a diode.
Rise and fall times of a typical 10ns long signal were 1-2 ns and the intensity
of the emission could be controlled by the supply voltage. The wavelength of
the radiation was 472 nm, which is blue in colour, but any longer or even
shorter wavelengths can similarly be used. The consistency of the experiment
and its theoretical model was analysed by computer simulations using OrCAD and
PSPICE.
