Patent ID: 7564021

Claim:
A pyroelectric sensor system comprising: an alternating voltage source for generating an alternating voltage at a predetermined frequency; a pyroelectric scene element responsive to the alternating voltage, said pyroelectric scene element for generating a hysteresis loop charge output in response to the alternating voltage, said alternating voltage driving the pyroelectric scene element over at least a portion of the hysteresis loop charge output of the pyroelectric scene element, said pyroelectric scene element being constructed and arranged so that the alternating voltage causes a polarization reversal of dipoles in the pyroelectric scene element in response to positive and negative changes of the alternating voltage; a charge integration system responsive to the charge output from the pyroelectric scene element, said integration system determining an area within the hysteresis loop defined by the hysteresis loop output and generating a signal indicative of the charge output from the pyroelectric scene element; a ferroelectric layer of the pyroelectric scene element being selected from a group consisting of strontium-bismuth-tantalate (SBT), barium-bismuth-tantalate, andlanthium-bismuth-tantalate; and the ferroelectric layer being disposed between a first and a second capacitive plate of the pyroelectric scene element.