Current driving system of light emitting diode

A current driving system of a light emitting diode comprising:

• an apparatus for measuring a concentration of light absorbing material in a living tissue, the apparatus including:
• a probe adapted to be attached to a living tissue, the probe having a light emitting section having at least two light emitting diodes emitting lights of different wavelengths, the probe further having a light receiving section defined by a photo-diode for receiving light emitted from the light emitting section after being transmitted through the living tissue;
• a measurement apparatus body, attached with the probe, for calculating the concentration of light absorbing material in the living tissue, said at least two light emitting diodes being successively and continuously driven by a light emitting diode driving circuit arranged in the measurement apparatus body;
• three current supply lines and connection terminals thereof for respectively driving said at least two light emitting diodes;
• a first pair of driving switches connected to a first of the three current supply lines, a first switch among the first pair having contact points switched to an electric power source and a second switch among the first pair switched to a ground;
• a second pair of driving switches connected to a second of the three current supply lines, a first switch among the second pair having contact points switched to the electric power source and the second switch among the second pair switched to the ground;
• and
• switching operation signal supply lines arranged for successively and continuously driving the light emitting diodes by supplying switching operation signals to the first and second pair of driving switches,
• wherein the driving switches and the signal supply line is disposed inside the measurement apparatus body.