TRANSIENT IMAGING DISPLACEMENT INTERFEROMETRY APPLIED TO SHOCK LOADING

Abstract

We have applied Transient Imaging Displacement Interferometry (TIDI) to copper targets loaded by laser‐launched flyers. TIDI captures the full‐field out‐of‐plane surface displacement map single‐shot with the time resolution of the illumination pulses (180 ps). Displacement sensitivity of ∼10 nm with lateral spatial resolution of ∼5 microns is achieved over our ∼1 mm2 field‐of‐view. A framing camera allows capture of up to eight displacement maps for a single loading event, allowing the evolution of the surface motion to be tracked. Point and line VISARs are used as complementary diagnostics that provide a temporally continuous record of the velocity history of the sample, and also provide time stamps for the TIDI displacement maps. The rich heterogeneity in the surface displacement due to the grain structure of the sample is readily measured.