The present patent application concerns new ligands of the H4-receptor, their process of preparation and their therapeutic use. Then, properly adjusting the kind and the concentration of dopants for manufacturing the optical fiber 1 for attenuating optical signal; simultaneously adding the dopant enabling the absorption of optical signal to increase with the wavelength become long and the dopant enabling the absorption of optical signal to decrease with the wavelength become long. The semiconductor modules and the cooler are held between the control boards.