OPTICAL HARTLEY TRANSFORMS

The two-dimensional Hartley transform is of particular interest not on ly as a tool for analysis and processing of images and other two-dimen sional functions, but because it can be implemented optically without introducing the phase ambiguities associated with intensity-only obser vations of Fourier transforms. The Hartley transform property of produ cing real transforms from real inputs means that square law detection introduces only a sign ambiguity, which can be resolved much more easi ly than a phase ambiguity. This suggests applications in optical signa l processing, holography, and optical diffraction.