Application of the Shack–Hartmann Wavefront Sensor for Monitoring the Parameters of a Supersonic Gas Jet

Abstract

Results of an experimental study of the density distribution in a small-size (1–2 mm in diameter) supersonic gas jet in vacuum are reported. The measurements are performed by the developed Shack–Hartmann wavefront sensor, which consists of a microlens array with 100 × 100 elements and a video camera with a resolution of 2048 × 2048 pixels. The reliability of measurements in terms of the space and time resolution, as well as in terms of the minimum levels of phase changes induced by the tested object, is analyzed.