{'fraction_non_alphanumeric': 0.022727272727272728, 'fraction_numerical': 0.0, 'mean_word_length': 5.360824742268041, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 1, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
Effect of fractal rough-surface Hurst exponent on speckle in imaging systems.

Speckle image contrasts from a fractal rough-surface object are investigated in simulation, where the image surface is conjugate to the object surface. It is observed that the Hurst exponent H of fractal roughness affects speckle contrast and statistics dramatically. For example, a strong rough surface (sigma(h)>lambda) exhibits Rayleigh statistics over increasing ranges of point spread function widths as H decreases. Conceptual explanations are also presented for effects of H and the coherence factor on speckle in imaging systems.