Acoustic tweezers based on standing surface acoustic waves (SAWs) enable contactless manipulation of microscale and nanoscale particles through acoustic radiation forces (ARFs) and acoustic streaming-induced drag forces. However, the effects of Fresnel interference on particle manipulation in the near field of SAW devices are often overlooked. Here, we employ a pair of straight-electrode interdigital transducers (IDTs) to generate standing SAWs in the Fresnel interference-affected near field for particle patterning. We observe lateral variations in SAW intensity along the electrode length, showing multiple periodically distributed SAW beams with relatively higher intensities. The number of these beams gradually increases with the IDT aperture size. Such intensity variations influence the ARFs acting on microparticles and nanoparticles, the resulting vortex streaming fields, and the streaming-induced drag forces, thereby affecting particle distributions. In particular, we observe size-dependent particle patterning in the near field with Fresnel interference. Polystyrene particles with diameters of 500 nm, $6\mathrm{\mu }\mathrm{m}$, and $20\mathrm{\mu }\mathrm{m}$ exhibit distinct behaviors: 500 nm particles are accumulated by streaming vortices due to dominant streaming drag effects; $20\mathrm{\mu }\mathrm{m}$ particles, primarily governed by ARFs, are trapped along pressure nodal lines while avoiding regions of high-intensity SAW beams; $6\mathrm{\mu }\mathrm{m}$ particles, influenced by both ARF and streaming effects, form discrete chains along pressure nodal lines while being attracted to regions with strong streaming vortices.

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• Acoustic forces
• Acoustic modeling
• Acoustic wave phenomena
• Acoustofluidics
• Surface acoustic wave