Related Experiment Video
Updated: May 6, 2026

High-speed Particle Image Velocimetry Near Surfaces
Published on: June 24, 2013
Beating Tunnel Vision: Near-Surface Velocity-Map Imaging
Nitish Pal1, Preeti M Mishra2, Paul D Lane1
1Institute of Chemical Sciences, Heriot-Watt University, Edinburgh EH14 4AS, U.K.
None:
We demonstrate a new methodology for applying velocity-map imaging (VMI) to the study of gas-surface dynamics that allows direct imaging of the scattering plane. By bringing the surface near to the ionization laser inside the VMI electrodes, we demonstrate a route to overcoming "tunnel vision", a term used to describe the limited angular acceptance of measurements taken at too great distance from where the gas-surface interaction takes place. Using a molecular beam of NO molecules colliding with a surface of highly oriented pyrolytic graphite as an exemplar system, we show the correlation between the laser-surface distance and the accessible scattering angular range. We demonstrate the capabilities of near-surface VMI (NS-VMI) through the analysis of speed and angular distributions derived from the images.
Related Concept Videos
Instantaneous Velocity - II
Velocity and Position by Graphical Method
Relative Motion Analysis - Velocity
When an external force is exerted, it sets the crank into a rotational movement. This, in turn, instigates the motion of the connecting rod, leading to what is referred to as a general plane motion. This process involves two key points - point A on the connecting rod...
Topographic Surveying and Contours
Plotting of Topographic Maps
Methods of Obtaining Topography

