A phased array ultrasound apparatus, the apparatus comprising: an array of ultrasound transducer elements; a plurality of first electrodes and a plurality of second electrodes, wherein each first electrode extends in a first direction in relation to the array of ultrasound transducer elements and each second electrode extends in a second direction, different from the first direction, in relation to the array of ultrasound transducer elements such that each transducer element in the array is associated with one first electrode and one second electrode; wherein each transducer element comprises a layer of piezoelectric material between the first electrode and the second electrode configured to control a vibration of the piezoelectric material to induce emitting of an ultrasonic wave by the transducer element based on a difference between the control signals applied to the first electrode and the second electrode with which the transducer element is associated, wherein control signals applied to a first electrode are shared by the transducer elements along the extension of the first electrode in relation to the array and control signals applied to a second electrode are shared by the transducer elements along the extension of the second electrode in relation to the array, and wherein the phased array ultrasound apparatus is configured to generate, by the shared control signals on the first electrodes and the second electrodes for each transducer element, a phase delay of the transducer element based on a desired phase delay for each of the transducer elements configured to form a combined ultrasonic wave; characterized in that: the piezoelectric material exhibits two polarization states, wherein a phase of an emitted ultrasonic wave by the transducer element differs 180° between the two polarization states of the piezoelectric material; and wherein the phased array ultrasound apparatus is configured to individually change polarization state of the piezoelectric material of selected ultrasound transducer elements, from one of the two polarization states of the piezoelectric material to the other of the two polarization states of the piezoelectric material, before activating at least a subset of the ultrasound transducer elements in the array to form the combined ultrasonic wave, wherein the ultrasound transducer elements for which the polarization state of the piezoelectric material is changed are selected based on a relation between the phase delay of the transducer element to be generated and the desired phase delay of the transducer element for forming the combined ultrasonic wave. an array of ultrasound transducer elements; a plurality of first electrodes and a plurality of second electrodes, wherein each first electrode extends in a first direction in relation to the array of ultrasound transducer elements and each second electrode extends in a second direction, different from the first direction, in relation to the array of ultrasound transducer elements such that each transducer element in the array is associated with one first electrode and one second electrode; wherein each transducer element comprises a layer of piezoelectric material between the first electrode and the second electrode configured to control a vibration of the piezoelectric material to induce emitting of an ultrasonic wave by the transducer element based on a difference between the control signals applied to the first electrode and the second electrode with which the transducer element is associated, wherein control signals applied to a first electrode are shared by the transducer elements along the extension of the first electrode in relation to the array and control signals applied to a second electrode are shared by the transducer elements along the extension of the second electrode in relation to the array, and wherein the phased array ultrasound apparatus is configured to generate, by the shared control signals on the first electrodes and the second electrodes for each transducer element, a phase delay of the transducer element based on a desired phase delay for each of the transducer elements configured to form a combined ultrasonic wave; the piezoelectric material exhibits two polarization states, wherein a phase of an emitted ultrasonic wave by the transducer element differs 180° between the two polarization states of the piezoelectric material; and wherein the phased array ultrasound apparatus is configured to individually change polarization state of the piezoelectric material of selected ultrasound transducer elements, from one of the two polarization states of the piezoelectric material to the other of the two polarization states of the piezoelectric material, before activating at least a subset of the ultrasound transducer elements in the array to form the combined ultrasonic wave, wherein the ultrasound transducer elements for which the polarization state of the piezoelectric material is changed are selected based on a relation between the phase delay of the transducer element to be generated and the desired phase delay of the transducer element for forming the combined ultrasonic wave.