Abstract
Joint transform correlation involves the recording and display of the joint power spectrum by sampling devices. The Nyquist condition for sampling a joint power spectrum depends on the distance between the input subimages, the size of the subimages, the focal length of the Fourier lens, and the light wavelength. Since the joint power spectrum is equivalent to a bandpass function, an undersampled joint power spectrum will lead to multiple interlaced outputs and the correlation spots and DC terms could either overlap or remain separate. The specifications pertaining to the sampling device are identified so as to be able to distinguish the correlation spots of interest in the interlaced output. ©