The present invention provides a method and apparatus of using
light-emitting elements for illumination as well as communication of
data, wherein potential flicker due to sub-fusion frequency data
correlations can be reduced compared to prior art techniques, while
reducing redundancy in the data transmission. The intensity of the
illumination from the light-emitting elements is controlled by a dimming
signal such as a pulse width modulation (PWM) signal or a pulse code
modulation (PCM) signal, for example. An amplitude-modulated data signal
is then superimposed on the dimming signal for communication of data. The
dimming signal thus acts as a carrier signal for the data signal. A
sensing means is then used to receive the data signal by detecting all or
part of the illumination from the light-emitting elements. The data
signal can subsequently be extracted from the detected illumination.