A system comprising: a suspended particle device SPD, wherein the suspended particle device includes: - a first conductive layer; - a second conductive layer; and - an emulsion including a plurality of suspended particles which align in a predetermined pattern when exposed to an electric field, wherein the emulsion is positioned between the first conductive layer and the second conductive layer; and a voltage controlling device, wherein the voltage controlling device includes; an AC terminal adapted to receive an AC voltage at a specific frequency; a voltage dividing device adapted to divide the AC voltage into a plurality of distinct voltage values within a predetermine range; a controller adapted to control the voltage dividing device to provide a selected voltage value based on voltage level information; and an SPD terminal device adapted to receive the selected voltage value; wherein: a first connecting bus connects the first conducting layer to the SPD terminal device; a second conducting bus connects the second conducting layer to the SPD terminal device; and the voltage dividing device further comprises: a capacitor array including a plurality of capacitors wherein each capacitor in the capacitor array has a predetermined capacitance; and a switch array, connecting the capacitor array to the SPD terminal device such that each switch of the switch array connects one capacitor of the capacitor array to the SPD terminal device, each of the capacitors of the capacitor array being connected to the SPD terminal device via a respective switch of the switch array, wherein: the controller controls the switches of the switch array to connect at least one of the capacitors of the capacitor array to the SPD terminal device based on the voltage level information. a suspended particle device SPD, wherein the suspended particle device includes: - a first conductive layer; - a second conductive layer; and - an emulsion including a plurality of suspended particles which align in a predetermined pattern when exposed to an electric field, wherein the emulsion is positioned between the first conductive layer and the second conductive layer; and - a first conductive layer; - a second conductive layer; and - an emulsion including a plurality of suspended particles which align in a predetermined pattern when exposed to an electric field, wherein the emulsion is positioned between the first conductive layer and the second conductive layer; a voltage controlling device, wherein the voltage controlling device includes; an AC terminal adapted to receive an AC voltage at a specific frequency; a voltage dividing device adapted to divide the AC voltage into a plurality of distinct voltage values within a predetermine range; a controller adapted to control the voltage dividing device to provide a selected voltage value based on voltage level information; and an SPD terminal device adapted to receive the selected voltage value; wherein: a first connecting bus connects the first conducting layer to the SPD terminal device; a second conducting bus connects the second conducting layer to the SPD terminal device; and the voltage dividing device further comprises: a capacitor array including a plurality of capacitors wherein each capacitor in the capacitor array has a predetermined capacitance; and a switch array, connecting the capacitor array to the SPD terminal device such that each switch of the switch array connects one capacitor of the capacitor array to the SPD terminal device, each of the capacitors of the capacitor array being connected to the SPD terminal device via a respective switch of the switch array, wherein: the controller controls the switches of the switch array to connect at least one of the capacitors of the capacitor array to the SPD terminal device based on the voltage level information. a first connecting bus connects the first conducting layer to the SPD terminal device; a second conducting bus connects the second conducting layer to the SPD terminal device; and the voltage dividing device further comprises: a capacitor array including a plurality of capacitors wherein each capacitor in the capacitor array has a predetermined capacitance; and a switch array, connecting the capacitor array to the SPD terminal device such that each switch of the switch array connects one capacitor of the capacitor array to the SPD terminal device, each of the capacitors of the capacitor array being connected to the SPD terminal device via a respective switch of the switch array, wherein: the controller controls the switches of the switch array to connect at least one of the capacitors of the capacitor array to the SPD terminal device based on the voltage level information.