Direct charge injection for the pyroelectric/CCD focal plane hybrid

The development of the pyroelectric vidicon has given rise to a range of inexpensive thermal imagers operating at ambient temperatures. More recently, solid state readout of large pyroelectric detector arrays has been reexamined with particular reference to the possibility of interfacing the pyroelectric array direct with a silicon charge-coupled device (CCD) chip. There are two general methods of making the coupling between detector and CCD. These are referred to as direct injection and gate modulation or voltage injection. In direct injection, the detector is coupled to an input diffusion on the silicon device. For a number of reasons, the direct injection method is preferred, and the present investigation is concerned with the mode of operation employed in connection with a use of this method. Theoretical models are developed to predict the signal injection efficiency and the noise properties for the direct injection mode. The theory is based on operation in weak inversion.