An apparatus for the imaging of gaseous fluid motion is disclosed. The apparatus includes a sub-nanosecond pulsed laser. The sub-nanosecond pulsed laser is configured to cause a particle species to fragment and for the recombining fragments subsequently to fluoresce. The apparatus also includes a gaseous fluid comprised of particle species. The apparatus also includes a time gated camera. The time gated camera configured to capture at least one image of the fluorescence from the recombining particle fragment species displaced after a specific time lapse following the laser pulse. Additionally, a fluid velocity can be calculated from a comparison of the image of the displaced particle species to an initial reference position and the time lapse. A Femtosecond Laser Electronic Excitation Tagging (FLEET) method of using the disclosed apparatus is also disclosed.
