A detection system that includes an emitter, a power supply source, a receiver, a detector, and a processor. The emitter includes a light-emitting diode that emits a luminous signal. The power supply source applies a constant voltage to the light-emitting diode. The receiver senses the luminous signal emitted by the light-emitting diode and generates a first input signal representative of the luminous signal detected. The detector measures the current passing through the light-emitting diode and generates a second input signal representative of the current measured. The processor is connected to the receiver and provides an output signal as a function of the first input signal and of the second input signal.