Visible light communication transmitter and visible light communication system

A visible light communication system, comprising:

• a visible light communication transmitter that drives a blue-light-excitation-type white LED based on a driving current signal generated in accordance with transmission data and outputs a visible light signal to a receiver, said visible light communication transmitter including a multi-level driving unit that generates a multi-level driving current signal by adding a rising pulse when the transmission data rises and adding a falling pulse when the transmission data falls;
• and
• a visible light communication receiver that receives the visible light signal output from the visible light communication transmitter, converts the received optical signal into an electric signal, and outputs received data,
• wherein a driving current value corresponding to the transmission data is equal to or smaller than ⅓ of a current value of at least one of the rising pulse and the falling pulse.

A visible light communication system, comprising:

• a visible light communication transmitter that drives a blue-light-excitation-type white LED based on a driving current signal generated in accordance with transmission data and outputs a visible light signal to a receiver, said visible light communication transmitter including a multi-level driving unit that generates a multi-level driving current signal by adding a rising pulse when the transmission data rises and adding a falling pulse when the transmission data falls;
• and
• a visible light communication receiver that receives the visible light signal output from the visible light communication transmitter through a color filter that removes at least a portion of light output from a phosphor of the blue-light-excitation-type white LED, converts the received optical signal into an electric signal, and outputs received data,
• wherein a driving current value corresponding to the transmission data is equal to or smaller than 5/4 of a current value of the rising pulse and the falling pulse.

A visible light communication system, comprising:

• a visible light communication transmitter that drives a blue-light-excitation-type white LED based on a driving current signal generated in accordance with transmission data and outputs a visible light signal to a receiver, said visible light communication transmitter including a multi-level driving unit that generates a multi-level driving current signal by adding a rising pulse when the transmission data rises and adding a falling pulse when the transmission data falls;
• and
• a visible light communication receiver that receives the visible light signal output from the visible light communication transmitter, converts the received optical signal into an electric signal, and outputs received data,
• wherein a modulation encoder is installed in the visible light communication transmitter, and a modulation decoder that decodes a modulation code modulated in the modulation encoder is installed in the visible light communication receiver, and
• wherein a run length limited code, which is DC free, of which an encoding rate is ⅔, and of which a minimum run is 1, is used as the modulation code, and NRZI modulation is performed.