True differential pyroelectric infrared detector with improved D* test results with analysis

Abstract

Pyroelectric infrared detectors are used in many commercial and industrial applications. Typically these devices have been “single ended” and thus any electronic perturbation from a non-detector related noise source such as line frequency interference or microprocessor clock and other sources of electronic noise can be coupled onto the detector’s output signal. We have solved this problem by employing a rather unique connection which also provides an increase in the signal to noise of any pyroelectric detector by a factor of the square root of 2 or by about 1.41 times greater than devices not utilizing this connection. Many devices using this connection have been built, fully tested and the data analyzed which provide a true differential or double ended output and the increase in D* as predicted. This scheme will work with any pyroelectric material (LTO, DLATGS, PLZT, PVDF etc.) with current or voltage mode impedance conversion and configurations such as parallel or series with and without temperature fluctuation compensation and of course with standard single elements. This talk will present this data and conclusions regarding the approach.