2025/09/29 by Andra Naresh Kumar Reddy, Reddy, Andra Naresh Kumar, Allam, Srinivasa Rao +10
Engineering · #Advanced Optical Imaging Technologies #Advanced optical system design #Electrowetting and Microfluidic Technologies #FOS: Physical sciences #Optics (physics.optics)
paper · pdf · doi:10.48550/arxiv.2509.24471
openalex publication_date 2025/09/29 · openalex created_date 2025/10/19 · openalex updated_date 2026/07/28
We introduce a novel method for creating a high-quality, sharply defined, non-diffracting optical bottle beam by focusing a Bessel beam propagating through a flat multi-level diffractive lens (MDL). This study highlights the impact of the MDL illuminated by a Bessel beam with suppressed sidelobes generated from a binary axicon. The resulting Bessel bottle beam exhibits a series of low- or zero-intensity zones interleaved with high-intensity regions, with variable periods ranging from 0.2 to 1.36 mm along the beam propagation. The transverse intensity profiles of these regions remain shape-invariant over long distances in free space, and thereby the non-diffracting range of the micron-sized optical bottle beam exceeds 5 cm. We also observe that the far-field output from the MDL illuminated by a Bessel beam offers advantages over conventional focusing lenses. Furthermore, this technique can operate on ultrafast timescales (from pico- to femtoseconds) due to the high damage thresholds of the binary axicon and MDL, enabling the generation of high-power optical bottle beams. Ultimately, our experimental approach paves the way for various applications, including high-resolution biological imaging in turbid media, particle manipulation, micromachining, and harmonic generation, leveraging the spatial landscape of the optical bottle beam.