The pyroelectric effect has been characterized for single-pixel elements consisting of strontium bismuth tantalate (SBT)
ferroelectric material as the sensing elements. These pixels have been integrated into second-generation focal plane
arrays. The constituent second-generation pixels include thermal insulating layers and an infrared absorber layer. The
MEMS-less arrays are operated in active mode, a technique that eliminates radiation choppers found in other passive
pyroelectric IR imagers. This paper addresses the results of precursor 2x2 to 14x14 second-generation arrays of SBT
elements, the active detection mechanism, and the unique read-out, interrogation signal, and the synchronization
electronics. The second-generation 14x14 pixels array was implemented to demonstrate the performance of an active
pyroelectric array as a precursor to larger size arrays using different pixel dimensions. The active mode detection
eliminates the use of a chopper, enables the dynamic partition of the array into pixel domains in which pixel sensitivity
in the domains can be adjusted independently. This unique feature in IR detection can be applied to the simultaneous
tracking of diverse contrast objects. In addition, by controlling the thickness of the absorber material the arrays can be
optimized for maximum response at specified wavelengths by means of quarter-wavelength interferometry.
A MEMS-less infrared pyroelectric sensor that employs an active detection mechanism based on a strontium
bismuth tantalate (SrBi2Ta2O9) ferroelectric sensing material is described and compared to passive modes of
operation. A model is based on fundamental performance of ferroelectrics in which the polarization state of the
material is actively interrogated enabling improved signal to noise ratio, greater effective pyroelectric
coefficient, and chopper-less design. In addition to excellent thermal responsivity in the medium and long
wavelength bands and unlimited endurance, the unique design enables selective wavelength tuning of
insulating layer and absorber materials to maximize the responsivity at distinct wavelengths.
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