Patent ID: 7800048

Claim:
A method for determining a change of temperature of a SBT pixel element, comprising: determining a first value indicating an amount of surface charge of the SBT pixel element due to a spontaneous polarization of the SBT pixel element at a first time; determining a second value indicating an amount of surface charge of the SBT pixel element due to a spontaneous polarization of the SBT pixel element at a second time; determining a third value proportional to a difference between the first value and the second value; determining a fourth value indicative of the change of temperature of the SBT pixel element based on the third value; and storing the fourth value indicative of the change of temperature of the SBT pixel element in a memory device, wherein the steps of determining the first and second value further include the first value being in relation to a first measured voltage value across a capacitor, said capacitor being in series electrical connection to the SBT pixel element, and the second value being in relation to a second measured voltage value across the capacitor.