Apparatus for processing an optical image for isolating shape content and characterization of the optical image, comprising: a source of coherent, monochromatic light for propagating a beam of planar polarized, coherent, monochromatic light along a beam path; an image input device positioned in the beam path, wherein the image input device has the capability of modulating the beam of light with spatially dispersed phase changes that result in diffracted light of the image in the beam; a focusing lens positioned in the beam path and shaped to focus the beam as modulated by the image input device to a focal point at a focal plane; a spatial filter positioned in the beam where a Fourier transform pattern of the image is presented in the beam that propagates from the image input device and the focusing lens; a projection lens positioned in the beam path; and a detector positioned in the beam path after the projection lens; characterized by: a first optical subsystem comprising the image input device, the focusing lens, and the spatial filter, wherein the image input device is positioned between the focusing lens and the spatial filter; and a second optical subsystem comprising the detector and the projection lens, wherein the projection lens has focal points (822, 824) at respective focal distances (F 2, F 2) on opposite sides of the projection lens, and wherein the second optical subsystem is optically coupled to the first optical subsystem with the projection lens and both of the focal points (822, 824) of the projection lens positioned in the beam path between the image input device and the detector and with the spatial filter positioned optically between the image input device and the projection lens. a source of coherent, monochromatic light for propagating a beam of planar polarized, coherent, monochromatic light along a beam path; an image input device positioned in the beam path, wherein the image input device has the capability of modulating the beam of light with spatially dispersed phase changes that result in diffracted light of the image in the beam; a focusing lens positioned in the beam path and shaped to focus the beam as modulated by the image input device to a focal point at a focal plane; a spatial filter positioned in the beam where a Fourier transform pattern of the image is presented in the beam that propagates from the image input device and the focusing lens; a projection lens positioned in the beam path; and a detector positioned in the beam path after the projection lens; characterized by: a first optical subsystem comprising the image input device, the focusing lens, and the spatial filter, wherein the image input device is positioned between the focusing lens and the spatial filter; and a second optical subsystem comprising the detector and the projection lens, wherein the projection lens has focal points (822, 824) at respective focal distances (F 2, F 2) on opposite sides of the projection lens, and wherein the second optical subsystem is optically coupled to the first optical subsystem with the projection lens and both of the focal points (822, 824) of the projection lens positioned in the beam path between the image input device and the detector and with the spatial filter positioned optically between the image input device and the projection lens. a first optical subsystem comprising the image input device, the focusing lens, and the spatial filter, wherein the image input device is positioned between the focusing lens and the spatial filter; and a second optical subsystem comprising the detector and the projection lens, wherein the projection lens has focal points (822, 824) at respective focal distances (F 2, F 2) on opposite sides of the projection lens, and wherein the second optical subsystem is optically coupled to the first optical subsystem with the projection lens and both of the focal points (822, 824) of the projection lens positioned in the beam path between the image input device and the detector and with the spatial filter positioned optically between the image input device and the projection lens.