The possibility of background limited pyroelectric detectors

Abstract The magnitude of the Johnson noise is compared with that of the background noise for TGS, LiTaO 3 , boracites and other pyroelectric materials. It is shown that the Johnson noise is a minimum at an angular frequency the reciprocal of the thermal time constant of the detecting element, and can then, for some materials, be significantly less than the background noise. The problems of producing a practical detector taking advantage of this property are discussed. An element of minimal thermal capacity combined with a very good low noise amplifier is required, but by exploiting modern techniques for fabricating electronic materials it should be possible to make devices significantly better than those now generally available and which at low frequencies approach background limited performance.