Multi-frame interferometric setup for studying quick-change processes

The design and application of a ten-frame interferometric setup for studying rapidly changing plasma processes are discussed. The setup basically consists of an optical delay line and a Jamin-type interferometer. The setup is tested for an optical scheme consisting of a neodymium laser, a ruby laser, a beam-formation system, a delay line, a prism system, a Jamin-type interferometer, filters, a multiframe camera, and a plexiglass target. The plasma and laser-spark interferograms obtained are presented and discussed along with the spatial distributions of plasma electron density determined on the basis of the interferograms. It is found that the proposed interferometric setup may be used for studying plasma optical inhomogeneities with linear dimensions up to 15 mm and has further applications in aerodynamics and hydrodynamics.