A data transmission system is disclosed, which transmits data via a touch panel capable of detecting vibrations, the system having: a portable apparatus including a vibration conversion unit configured to convert arbitrary data into a vibration signal, and a vibration generation unit configured to generate vibrations corresponding to a pattern of the vibration signal; and a touch panel apparatus including a resistive film-type touch panel configured to input the vibrations upon receiving a contact of the portable apparatus, a signal conversion unit configured to convert, into a detection signal, a voltage level detected corresponding to a contact and a non-contact between resistive films of the resistive film-type touch panel based on the inputted vibrations, and a data detection unit configured to detect the data based on a pattern of the detection signal.
