<title>Diffuse reflectivity measurement of tungsten target under shock compression</title>

Abstract

An optical technique, which measures directly reflection ratio of a rough target surface in shock compression, is introduced. This technique uses laser as light source to illuminate target surface and measures light power scattering from randomly rough surface with two differently axial angles simultaneously. Reflectivity and lightness function about tungsten target surface in shock compression are deduced with variation of light power. In experimental system, polarizing beamsplitters separate laser from radiation of heat partially. The radiation of heat, which produces noise in signals, is eliminated completely by subtraction of S polarizing light beam from P polarizing beam. Reflection coefficient of tungsten target in shock-compression has been investigated and initial experiment results show: when tungsten target is shock- compressed at 165 Gpa pressure, relative change of reflection ratio compared to unshock- compression is only several times. Discussions and analyses about the technique and experimental results are also done in the end of the paper.© (1995) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.