ACQUISITION BY STARING FOCAL-PLANE ARRAYS - PIXEL GEOMETRY-EFFECTS

Spatial averaging techniques have been used to compare signal acquisit ion (i.e., detectivity performance) of hexagonally sampled equivalent- area rectangular, hexagonal, and rhombic pixel arrays. In the absence of noise, rhombic focal-plane arrays (FPAs) are found to be associated with a modulation transfer function, which is almost identical to tha t of the rectangular FPA. However, while detecting noisy signals, the probability density function of the detected signal of the rhombic FPA is found to be smaller than that of hexagonal FPA, but higher than th at of the rectangular FPA. At large noise variances, all three staring arrays perform almost the same in acquisition of signal.