Single-camera plenoptic imaging multiplexes the angular domain into the spatial domain typically using a microlens array (MLA). Fourier integral microscopy (FIMic) is the latest evolution of plenoptic imaging applied to microscopy, otherwise referred to as integral microscopy, and offers the highest spatial resolution of all the integral microscopic techniques. This approach places the MLA at the Fourier plane (or aperture stop) of a microscope objective and the sensor one microlens focal length away. We use the term plenoptic 3.0 (p3.0) to refer to the FIMic architecture after the initial approach of p1.0 (or unfocused plenoptic) and p2.0 (or focused plenoptic).
Micro-plenoptic 3.0 (p3.0) MTV
We present instantaneous measurements of the three-dimensional velocity field containing two wall parallel velocity components (3D-2C) in an axisymmetric stagnation jet flow. This well-known flow is chosen to benchmark the novel velocimetry technique presented herein where Molecular Tagging Velocimetry (MTV) is used in conjunction with FIMic to obtain 3D-2C measurements with a single camera. The experiments herein utilize the Richardson Lucy Deconvolution algorithm to obtain voxels with 2 μm and 33 μm lateral and axial resolutions, respectively.
Main publications
SW WILLIAMS, S PORTAL, MJ YAMAKAITIS, C FORT, and PM BARDET. New compact design for a Fourier lightfield microscope, AIAA SciTech, Orlando, FL, Jan. 8-12 2024 https://arc.aiaa.org/doi/10.2514/6.2024-2494
PD HUCK, C FORT, and PM BARDET. Wall shear stress measurements using a MTV-based plenoptic microscope, AIAA SciTech, National Harbor, MD, Jan. 23-27 2023 https://doi.org/10.2514/6.2023-2491
PD HUCK, C FORT, and PM BARDET. Wall shear stress measurements using a MTV-based plenoptic microscope. 20th International Symposium on Applications of Laser and Imaging Techniques to Fluid Mechanics, Lisbon, Portugal, 11-14 July 2022.
Micro-p3.0 PTV
We also introduced a novel approach for comprehensive flow analysis within microfluidic systems by integrating particle tracking velocimetry (PTV) and shake-the-box (STB) techniques with plenoptic imaging. By combining the strengths of PTV and STB, which offer particle trajectory tracking and high-resolution particle position determination, respectively, our method enables accurate and detailed flow characterization. Leveraging Fourier light-field microscopy, a recent development of plenoptic imaging (or integral microscopy), we eliminate the need for multiple imagers and achieve high-resolution three-dimensional flow measurements using a single high-speed camera.
Macro-p3.0 PTV
We designed a novel plenoptic camera architecture and demonstrated its ability to perform three-dimensional three-component velocimetry. The architecture directly creates multiple views of a scene side by side on the camera sensor which can be treated independently. We looked at the flow induced by an oscillating rod and compared the results with the analytical solution to validate the results.
Main publications
M YAMAKAITIS, S PORTAL, PD HUCK, SW WILLIAMS and PM BARDET. Novel Single-Camera Light Field Imager for Three-Dimensional Measurements, 76th Annual Meeting of the APS Division of Fluid Dynamics, Washington, DC, Nov. 19-21 2023 https://meetings.aps.org/Meeting/DFD23/Session/G21.4