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LEDs, short for Light Emitting Diodes, are tiny semiconductor chips
that generate light when electrified. It takes a small amount of
electricity to make an LED glow (emit electrons), and the elements
that the diode is made from determine the light spectrum it emits. An
LED is backed by an internal reflector and encased in an epoxy body
with an integrated lens. Together, these components determine the
angle of the light emitted by the diode, which is shaped as a downward-
facing cone. Individual LEDs produce relatively small light cones, so
they are clustered into arrays so the light cones overlap, increasing
light intensity and coverage area.


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