In an organic electroluminescence device including a cathode and an anode, at least an emitting layer and an electron transporting layer are provided between the cathode and the anode. , particularly those implemented on mobile communication devices. The at least one optical bus is configured to be optically coupled to at least one source of input optical signals, to at least one optical detector, and to a plurality of reflective sensing elements. In some embodiments, capping layers or proximity masks can be used in conjunction with the flash lamp annealing. The pad part includes a metal pad layer formed on an undersurface of the LTCC substrate and a solder layer formed on an undersurface of the metal pad layer.