One of the fundamental quests in science is to maximize the three-dimensional spatiotemporal information retrieved from a sample.

Optical microscopes are the tool-of-choice to study highly dynamic events at sub-cellular resolution in areas as relevant as flow cytometry or neuroscience. However, current three-dimensional (3D) microscopy architectures offer an inherent tradeoff between spatial resolution, volume imaged, and time required to acquire a frame. As a result, several biological processes, including neuronal communication, protein aggregation, or virus trafficking, are currently studied with sub-optimal tools that lack the speed or spatial resolution to fully characterize these key events. Simply put, the absence of faster 3D imaging technologies impedes gaining a full understanding of how brain function, virus diffusion or other fast phenomena occur, and consequently, imposes a heavy burden on the development of therapeutic pathways to treat neurodegenerative diseases or advanced vaccines. 

We make efforts to address this issue by developing 3D microscopes that feature unprecedented imaging speeds

Research highlights

Variable optical elements for fast focus control

New review paper published in Nature Photonics! In this Review, we survey recent developments in the emerging field of high-speed variable z-focus optical elements, which are driving important innovations in advanced imaging and materials processing applications. Three-dimensional biomedical imaging, high-throughput industrial inspection, advanced spectroscopies, and other optical characterization and materials modification methods have made great strides forward in recent years due to precise and rapid axial control of light. Three state-of-the-art key optical technologies that enable fast z-focus modulation are reviewed, along with a discussion of the implications of the new developments in variable optical elements and their impact on technologically relevant applications.

Volumetric Lissajous confocal microscopy with tunable spatio-temporal resolution

New paper published in Biomedical Optics Express. Here, we developed volumetric Lissajous confocal microscopy to achieve unsurpassed 3D scanning speed with a tunable sampling rate. The system combines an acoustic liquid lens for fast focus translation with a resonant scanning mirror. Accordingly, the excitation beam follows a dynamic Lissajous trajectory enabling sub-millisecond acquisitions of image series containing 3D information at a sub-Nyquist sampling rate. By temporal accumulation and/or advanced interpolation algorithms, the volumetric imaging rate is selectable using a post-processing step at a desired spatiotemporal resolution. We demonstrate multicolor and calcium imaging over volumes of tens of cubic microns with 3D acquisitions speeds of 30 Hz and frame rates up to 5 kHz.

Acousto-optic systems for advanced microscopy

New paper published in Journal of Physics Photonics. In this article we review the operational principles, optical properties, and recent applications of acousto-optic systems for advanced microscopy, including random-access scanning, ultrafast confocal and multiphoton imaging, and fast inertia-free light-sheet microscopy.

 Micromixing with spark-generated cavitation bubbles

Micromixing or the ability to mix fluids within one microchannel is one of the central issues in microfluidics. In this paper, developed a novel approach to address this issue. Our idea is based on using cavitation bubbles generated with an electrical spark. The collapse of the so-generated bubbles induce turbulence, thus allowing controlled mixing at microsecond time scales.