Optical Pin Beams: Research Progresses and Emerging Applications

TL;DR

Optical pin beams (OPBs) introduce a momentum-space beam engineering paradigm that suppresses transverse wave vectors to achieve highly collimated, self-healing propagation with extended depth of focus. The review compiles the underlying physics, generation methods (notably phase masks on SLMs and high-power quartz modulators), and experimental demonstrations, including kilometer-scale turbulence and rain–fog testing. It highlights several OPB derivatives—vortex, vector-vortex, inverted, and vortex-inverted OPBs—that expand control over amplitude, phase, polarization, and OAM, and surveys emerging applications in free-space and underwater communications, optical trapping, and hyper-sampling imaging. The authors discuss practical prospects and challenges, arguing for future convergence with metasurfaces, adaptive optics, and machine-learning–assisted control to enable robust, scalable photonic systems.

Abstract

Optical pin beams (OPBs) represent a novel class of structured light fields engineered for resilient, long-distance propagation. Their exceptional stability and strong resistance to atmospheric turbulence make them a compelling alternative to conventional Gaussian and other structured beams for free-space optical systems. This review provides a comprehensive overview of the physical principles, generation strategies, experimental realizations, and emerging applications of OPBs. By precise spatial modulation of the optical wave vectors, OPBs achieve highly collimated, self-reconstructing propagation with distinctive pin-like features that confer remarkable robustness and self-healing capability. We further discuss several OPB derivatives--including vortex, inverted, and vortex-inverted OPBs--which expand the functional landscape by enabling flexible control over amplitude, phase, polarization, and orbital angular momentum. Experimentally, OPBs have demonstrated outstanding performance across diverse platforms, ranging from free-space and underwater optical communications to optical trapping and super-resolution imaging. With their unique combination of propagation stability, light-field tunability, and environmental adaptability, OPBs hold strong promise for next-generation optical communication, precision sensing, and advanced imaging technologies. This review summarizes recent research progresses in OPBs and highlights key opportunities and prospects for advancing their scientific discoveries and practical applications.

Figures (20)

• Figure 1: Timeline of key milestones in the development of Optical Pin Beams (OPBs). OPBs were introduced as a new class of structured light engineered to enable quasi-one-dimensional, pin-like propagation distinct from conventional Bessel and Airy beams. Initial experiments demonstrated highly collimated, diffraction-resilient OPB propagation with exceptional robustness against atmospheric turbulence and scattering (2019-2021). Over the past few years, the OPB framework has been expanded to include vortex, inverted, and vortex-inverted OPBs, integrating phase singularities, intensity inversion, and polarization control while preserving intrinsic propagation stability (2023-2025). Since their first demonstrations, OPBs have been applied to free-space and underwater optical communications, optical trapping, particle manipulation, and super-resolution imaging, benefiting from strong axial confinement, self-reconstruction, and reduced environmental sensitivity (2022-2025)555657585960616263646566. Current research efforts are advancing OPBs toward high-power operation, integration with adaptive optics, and propagation in nonlinear and bio–soft-matter systems, targeting turbulence-immune communication, precision sensing and detection, and versatile multifunctional photonic platforms.
• Figure 2: Mechanisms of atmospheric turbulence affecting laser beam transmission. (a) Schematic illustration of turbulence-induced disturbances during propagation. (b) Distortion of beam spot morphology. (c) Fluctuation of coupling power caused by temporal instability. (d) Centroid drift of the beam spot resulting from spatial randomness.
• Figure 3: Numerical simulation of the mechanism for constructing a stable optical field through the elimination of transverse wave vectors (a, b), and simulation results of generating a stable optical field using multiple ring beams, compared with the transmission behavior of a GS (c, d). In (c), the inner and outer diameters of adjacent rings are identical. In (d), the white dashed line denotes the transmission envelope of a GS with the same initial spot size; the red short lines mark the beam waist positions of the two beams. The region between the red and blue short lines corresponds to the Rayleigh length of the GS, while the region between the red and green short lines represents the Rayleigh length of the stable optical field168.
• Figure 4: (a) Schematic diagram of constructing an OPB using truncated Airy beam ring array and illustration of elimination of transverse wavevectors during subsequent propagation55. (b) Numerical simulation results showing the OPB construction with N=4, 8, and 32 Airy-beam ring arrays.
• Figure 5: (a)–(c) Simulation results showing the Poynting vector distribution of the OPB at different propagation distances55. (d) Simulation of OPB propagation in turbulence using the phase screen method55. (e) Experimental demonstration of the self-healing characteristic of the beam spot under obstacle occlusion conditions170.