A data transfer method used in such a case that data is transferred via a physical transfer system among a plurality of independently provided transmitterreceiver apparatuses. In one exemplary implementation, a method may comprise using ion beam deposition to deposit a first multilayer stack of thin films on a substrate to planarize and smooth surface defects on the substrate. The protection circuit includes two bipolar transistors in series, where the transistors are coupled between the supply voltage terminalbus and the reference voltage terminalbus. The first reflective plate reflects the incident wave in such a manner that the first reflected wave has a polarization different from a polarization of the incident wave.