Bessel and annular laser beams offer intriguing possibilities for material processing. However, current beam shaping methods can be limited in tunability, speed, or parallelization possibilities. Here, we show how ultrasounds in liquids enable generating user-selectable arrays of Gaussian, Bessel-like, or annular beams. By cascading two liquid-filled acoustic cavities, each with a different geometry, light control can be achieved at microsecond time scales. Such an acousto-optic technology is easy to implement in current laser-direct writing workstations, providing an unprecedented ability to tune light fields based on application.
Light-sheet microscopes with an extended depth of field (EDOF) offer a simple but powerful route toward fast volumetric imaging. However, methods for EDOF typically result in a loss of signal-to-noise ratio. Here, we propose a parallelization strategy as a simple solution. By illuminating multiple acoustically generated light sheets at different axial positions within the EDOF, and following an encoding sequence, information from several in-focus planes can be simultaneously retrieved. After applying a decoding algorithm, volumetric images are reconstructed with enhanced signal and level of detail. Our strategy paves the way for exploiting the full speed capabilities of EDOF light-sheet systems.
Laser-based systems are fundamental tools in several research and industrial fields as important as optical imaging and material processing. They grant high precision and flexibility, though, the throughput of these processes is constrained by their inherent point-scanning nature. An effective solution to this problem is beam parallelization, though, current implementations suffer from lack of flexibility, long response time or optical aberrations. In order to overcome these issues, we propose an original acousto-optofludic (AOF) device that exploits mechanical vibrations in a liquid to diffract light in a comb of multiple beams. In this work, we detail design, implementation, and optical characterization of AOF-based multi-focal laser system. In particular, we show that the main features of the acoustically generated beamlets can be tuned by properly varying frequency, amplitude, and phase of the mechanical oscillations. The application of this device to laser direct writing will enable high throughput processes of various materials in an highly tunable way.