Patent ID: 7689130

Claim:
An apparatus comprising: a) a plurality of light-emitting elements configured to emit a variable intensity visible light for both general illumination and a communication of data; b) a control means for generating a continuous carrier signal for controlling a luminous flux output of the plurality of light-emitting elements, the carrier signal comprising a plurality of phase-shifted dimming signals for the plurality of light-emitting elements, respectively, each of the plurality of dimming signals having a duty cycle for operation of an associated light-emitting element included in the plurality of light emitting elements; c) a modulation means for generating a data signal including encoded data for superposition on the carrier signal thereby forming a control signal for further controlling the luminous flux output of the plurality of light emitting elements in a manner that does not result in a visible flicker, the control signal formed by employing a peak amplitude modulation of substantially less than 100%, wherein the control signal is formed with the encoded data unconstrained by a minimum duty cycle of at least one of the plurality of dimming signals; d) a sensing means for detecting at least a portion of the luminous flux output; and e) means for extracting the data signal from the detected luminous flux output.