^{1)Institut Non-linéaire de Nice (France)
2)Imedea-Universitat de les Illes Balears (Spain)
3)Istituto Nazionale di Ottica, Firenze (Italy)}

• In some non linear systems noise can improve the degree of “order”
• Excitable systems
• Coherence Resonance
• Semiconductor Laser with Optical Feedback
• Experimental Set-up
• Output Intensity Controlling Noise Level
• Statistics of the Excitable Pulses
• Joint Entropy of the Excitable Pulses
• Conclusions