Antoni J. Wojcik | Searcharxiv

arXiv2026

Digital twin for full field-of-view Fraunhofer holographic patterning

Computer-generated holography allows for nearly complete dynamic control of optical fields, but discrepancies between idealised propagation models and physical hardware limit its performance, particularly across large fields of view. We present a compact differentiable model of a Fraunhofer holographic projector which describes the complete propagation chain, from a phase-only spatial light modulator (SLM) to the camera recording the focal plane of a Fourier lens. It uses physically interpretable parameters for the SLM, illumination, pupil, coherent stray light, and camera. The model is identified in situ from noise-probed hologram-image pairs without additional hardware, system modification, or camera-in-the-loop refinement. The recovered digital twin is used to generate holograms for patterns spanning the entire first diffraction order of the SLM at its spatial-bandwidth limit. This full-field capability is enabled by measuring field-dependent pupil aberrations and compensating severe inter-pixel crosstalk by operating at the $4π$ phase modulation range. The stray light responsible for residual zeroth-order artefacts is recovered in amplitude and phase, allowing its physical origin to be investigated, and its contribution suppressed during hologram synthesis. The work establishes a framework for calibration-aware field synthesis in holographic systems operating in the Fraunhofer regime for applications such as maskless lithography and optical tweezer arrays.

physics.optics↗

arXiv2026

Global Self-Attention with Exact Fourier Propagation for Phase-Only Far-Field Holography

Wavefront control underpins a wide range of technologies spanning imaging, communication, and light-matter interaction, yet remains fundamentally challenging due to the globally coupled nature of Fourier optical propagation. Computer-generated holography, using phase-only spatial light modulators, provides a widely used framework for wavefront manipulation. In the Fraunhofer (far-field) regime, propagation reduces to a Fourier transform, such that each modulator element influences the entire reconstructed field, rendering hologram synthesis a non-local inverse problem [1]. This coupling fundamentally limits conventional approaches. Iterative phase-retrieval methods [2-4] can stagnate and trade computation for quality, while camera-in-the-loop strategies remain tied to iterative refinement and near-field applications [5-7]. Learning-based approaches have accelerated hologram synthesis, yet largely rely on local inductive biases and Fresnel (near-field) models, leaving the fully coupled nature of the strict Fraunhofer regime unaddressed [8]. Here we show that the globally coupled structure of Fourier propagation maps naturally onto self-attention, enabling direct modeling of long-range dependencies in hologram synthesis. We demonstrate single-shot, high-fidelity phase-only hologram generation at inference in both simulation and experiment and show that integration with camera-in-the-loop training and a learnable phase corrector enables adaptive wavefront control under real optical conditions. These results establish self-attention as a scalable framework for wavefront control in complex optical systems and introduce attention-based modeling as a general approach to inverse problems governed by long-range interactions in wave physics.

physics.optics↗