Plane-Dependent Occlusion and Direction-Reversed Fringe Extinction in the Double-Slit Experiment v1.0

The double-slit experiment is traditionally treated as a static demonstration of interference arising from coherent superposition, with the positions of source, apertures, and detector held fixed. In this work, we report a previously undocumented operational regime of the double-slit experiment involving dynamic, plane-dependent occlusion. Using the human eye and a mobile-phone camera as detectors, we demonstrate that a laterally moving opaque barrier produces qualitatively different interference extinction depending on whether it is introduced before or after the slit plane.When the occluder is positioned between the source and the slits, interference fringes disappear in the intuitive direction of occluder motion, consistent with reduced illumination of the apertures. In contrast, when the occluder is positioned between the slits and the detector, fringe extinction propagates in the opposite direction, proceeding fringe-by-fringe from the opposing slit edge. This direction-reversed, fringe-resolved extinction is robust, reproducible, independent of slit orientation, dependent on the focal plane of observation, and identical for eye-based and camera-based detection. The effect is absent for a single opaque edge, confirming that it requires a structured multi-path interference field.Although fully compatible with classical wave and Fourier optics, there exists no prior experiment that explicitly isolates, demonstrates, or describes this behavior within the context of the double-slit experiment. The novelty of this work lies in the experimental isolation and interpretation of a regime in which interference evolution is governed by angular-mode accessibility rather than by spatial shadowing.We further interpret the observations in terms of entropic energy and information density. Dark interference fringes correspond to regions of low entropic energy and low information density, where local energy flux is minimized and phase relationships are maximally constrained. Post-aperture occlusion preferentially suppresses angular propagation modes associated with these low-entropy nodes, causing extinction to originate from dark fringes rather than from bright regions or geometric boundaries.We designate this behavior the Angular-Mode Occlusion Reversal (AMOR) effect. The results clarify the non-shadow nature of diffraction, highlight the operational nonequivalence of pre- and post-aperture occlusion, and expose an under-described experimental regime of the double-slit experiment that bridges classical optics with interaction-centric interpretations of interference.