Super‐Resolution and High‐Data‐Density Acoustic Meta‐Hologram via Amplitude and Phase Coupling

ABSTRACT

Image pixel density is a key factor limiting image clarity, while the scalar spatial bandwidth product (SBP) is the critical parameter determining the resolution of acoustic holographic imaging. Under finite SBP conditions, achieving high‐resolution imaging remains a significant challenge for current acoustic meta‐hologram techniques due to the constraints imposed by the diffraction limit of sound waves. To address the resolution and data density limitations of acoustic holography at the diffraction limit, we propose a super‐resolution and high data density holographic imaging method at low SBP based on amplitude‐phase coupling modulation mechanisms. By revealing the relationship between amplitude‐phase coupling and acoustic energy conservation, we derive a high‐resolution focused phase distribution suitable for low SBP under acoustic energy conservation constraints. Introducing coupled focused phases into the hologram enables super‐resolution acoustic field reconstruction and high‐data‐density information transmission at low SBP, providing a theoretical basis for overcoming the diffraction limit. We demonstrate the proposed concept of super‐resolution and high‐data‐density hologram through theoretical derivation, numerical simulation, and experimental validation. This super‐resolution holographic imaging method, based on amplitude‐phase coupling modulation under acoustic energy conservation constraints, provides a conceptually advanced technical approach for achieving high‐resolution acoustic hologram under low data density.