Spatial frequency analysis with a new incoherent optical approach.
A new approach to spatial frequency analysis is presented that offers the potential of analyzing 2-D distributions at video frame rates. It uses a light panel (or light shutter) whose light intensity distribution (or light transmission distribution) sequentially scans through all possible spatial frequencies in both magnitude and orientation. The spatial frequency spectrum of the transparency (or scene) onto which the panel is imaged can be directly displayed as a TV-type picture at video rates.
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