A rotating mirror allows a laser sheet to be swept through the experimental test section at rates of 10 Hz. A high speed camera is positioned such that it is normal to the sheet (when the sheet is vertical). Images are acruied in bursts of 200 frames. Provided that the current moves slower than the sheet sweeps the test section, image sets can be thought of as capturing a single, quasi-static scene. Image sets are reprojected into 3D space (e.g. pixel positions i,j are converted to real-world x,y,z coordinates based upon the orientation of the image sheet) and then filtered for "current" versus "not current" voxels. Resulting groups of volxesl may be imaged in 3D (right side of figure) and measurements of volume and surface area can be made.
Swept laser for 3D imaging of dynamic processes (Disco Laser)