Abstract: Optical field manipulation, as an emerging frontier in photonics, demonstrates significant potential in biomedical microscopy, quantum state engineering, and micro-nano fabrication. Addressing the critical limitation of current optical modulation technologies in achieving full-parameter precision control, this study proposes a novel approach for dynamic azimuthal light field modulation using dual spiral arrays. By designing spatially interleaved spiral structures with differential initial radii while maintaining identical periodic parameters, we achieved continuous optical modulation spanning the full 0 - 2π range in azimuthal field distribution. Through rigorous numerical simulations, we systematically established the quantitative correlation between structural parameters and azimuthal light field patterns, revealing for the first time a quasi-linear relationship between radius difference and resultant optical distribution. This theoretical framework not only advances fundamental unde