A driving method and a driving device are provided for an LED element in
which light emitting layers different from each other in light emission
wavelength peak, put on each other with a barrier layer being interposed,
are sandwiched by a pair of p-type and n-type layers, and color of
emitted light from which substantially depends only upon driving current
value. The method comprises a driving current value calculation step of
obtaining a value for designating a current value corresponding to a
desired color of emitted light from the LED element; a driving current
generation step of generating a driving current having the current value
designated by the value obtained in the driving current value calculation
step; and a driving current supply step of supplying the LED element with
the driving current generated in the driving current generation step.