Pyroelectric detectors have the advantage of being inherently accoupled to the target scene and they are therefore ideally suited for use in high-background and/or long-wavelength thermal imaging systems. This paper presents the results of a study to determine the feasibility and to predict the performance of focal planes employing very thin pyroelectric detector arrays together with solid-state readout circuitry. Detectivities within a factor of two of the radiation-limited performance have been achieved by wire bond connecting pyroelectric detectors to a Hughes CCD with a modulating gate input. It is shown that the voltage responsivity is symmetric with respect to the thermal and electrical time con-stants; the traditional role of these time constants (Tpc < Til) can be reversed to that Tw. becomes greater than Tth. The lumped parameter analysis creaks down for very thin detectors when the thermal time constant must be severely adjusted and for detector arrays in the absence of adequate thermal isolation between elements; in this case, thermal spreading must be accounted for. A more extensive treatment utilizing a thermal diffusion analysis allows such cases to be considered.