A beam scanning apparatus comprising: a plurality of antenna resonators disposed two-dimensionally in a row direction and a column direction; a plurality of row voltage lines each of which are configured to provide one of a plurality of row driving voltages in the row direction; a plurality of column voltage lines each of which are configured to provide one of a plurality of column driving voltages in the column direction; and a driving voltage conversion circuit configured to control a driving voltage applied to one of the plurality of antenna resonators based on a row driving voltage that is provided from one of the plurality of row voltage lines and a column driving voltage that is provided from one of the plurality of column voltage lines, and characterized in that the driving voltage conversion circuit comprises: a first transformation circuit configured to add the row driving voltage that is provided from the row voltage line corresponding to the driving voltage conversion circuit and the column driving voltage that is provided from the column voltage line corresponding to the driving voltage conversion circuit; a second transformation circuit configured to output an output voltage of the first transformation circuit based on the output voltage of the first transformation circuit being less than a threshold voltage at which a phase shift of reflected light caused by the one of the plurality of antenna resonators is at a maximum, and output a voltage obtained by subtracting the threshold voltage from the output voltage of the first transformation circuit based on the output voltage of the first transformation circuit being greater than the threshold voltage; and a third transformation circuit configured to alter an output voltage of the second transformation circuit according to non-linearity between the driving voltage applied to the one of the plurality of antenna resonators and the phase shift of the reflected light caused by the one of the plurality of antenna resonators. a plurality of antenna resonators disposed two-dimensionally in a row direction and a column direction; a plurality of row voltage lines each of which are configured to provide one of a plurality of row driving voltages in the row direction; a plurality of column voltage lines each of which are configured to provide one of a plurality of column driving voltages in the column direction; and a driving voltage conversion circuit configured to control a driving voltage applied to one of the plurality of antenna resonators based on a row driving voltage that is provided from one of the plurality of row voltage lines and a column driving voltage that is provided from one of the plurality of column voltage lines, and characterized in that the driving voltage conversion circuit comprises: a first transformation circuit configured to add the row driving voltage that is provided from the row voltage line corresponding to the driving voltage conversion circuit and the column driving voltage that is provided from the column voltage line corresponding to the driving voltage conversion circuit; a second transformation circuit configured to output an output voltage of the first transformation circuit based on the output voltage of the first transformation circuit being less than a threshold voltage at which a phase shift of reflected light caused by the one of the plurality of antenna resonators is at a maximum, and output a voltage obtained by subtracting the threshold voltage from the output voltage of the first transformation circuit based on the output voltage of the first transformation circuit being greater than the threshold voltage; and a third transformation circuit configured to alter an output voltage of the second transformation circuit according to non-linearity between the driving voltage applied to the one of the plurality of antenna resonators and the phase shift of the reflected light caused by the one of the plurality of antenna resonators. a first transformation circuit configured to add the row driving voltage that is provided from the row voltage line corresponding to the driving voltage conversion circuit and the column driving voltage that is provided from the column voltage line corresponding to the driving voltage conversion circuit; a second transformation circuit configured to output an output voltage of the first transformation circuit based on the output voltage of the first transformation circuit being less than a threshold voltage at which a phase shift of reflected light caused by the one of the plurality of antenna resonators is at a maximum, and output a voltage obtained by subtracting the threshold voltage from the output voltage of the first transformation circuit based on the output voltage of the first transformation circuit being greater than the threshold voltage; and a third transformation circuit configured to alter an output voltage of the second transformation circuit according to non-linearity between the driving voltage applied to the one of the plurality of antenna resonators and the phase shift of the reflected light caused by the one of the plurality of antenna resonators.