1. Matrix code reading apparatus comprising an ultrasound transducer which comprises transmitter and receiver electrodes, and a receiver unit connected to the receiver electrodes for processing the signals received by the receiver electrodes, wherein further comprising a transmitter module connected to the transmitter electrodes, and a pulse selection module comprising a number of pulse shapes and a number of features corresponding to the pulse shapes, the transmitter module being connected to the pulse selection module, and is transferring an electronic signal to the transducer, where the signal shape is selected based on the features of the matrix code to be read.