Multi-view three-dimensional display using a single-layer binary diffractive optical element

Single-layer diffractive optical elements (DOEs) often face limitations such as a narrow viewing angle and low resolution in the anti-counterfeiting field. To address the limitations of conventional single-layer DOEs, an optimized binary DOE scheme with a three-dimensional (3D) visual effect is proposed to enhance visual quality without increasing fabrication complexity. The DOE is divided into multiple sub-DOEs (SDOEs), each corresponding to an independent viewing angle. A modified iterative Fourier transform algorithm (M-IFTA) is employed to optimize each phase-only SDOE. Based on a variable-scale diffraction model with a spatial frequency tunable method (SFTM), the algorithm incorporates the Soft Quantization (SQ) process and employs a zero-padding operation to align the reconstructed images of all SDOEs at the same spatial position. The zero-padding not only enables continuous parallax and realistic 3D perception but also isolates edge signals, thereby enhancing reconstruction accuracy. Experimentally, a DOE achieving an angular sampling range of 36° × 36° (from -18° to 18° in both horizontal and vertical directions, with 2° steps and 19 × 19 views) was demonstrated, where each SDOE exhibited a view resolution of 900 × 900. This work significantly enhances the 3D visual performance of two-level DOEs while maintaining low fabrication complexity, offering a promising route toward efficient, low-cost, and high-security holographic anti-counterfeiting applications.