Image analyses of ICF target by X-ray measurement

The X-ray radiography technique was used to measure ICF targets and record film images of microspheres using contact microradiography. Then the film images were set under the microscope and converted to digital images by a CCD camera. Based on the information of these digital images, a computer algorithm has been developed for calculating the target shell parameters. This accepted procedure first locates the center of the microsphere using radial averaging of X-ray images, then calculate the radial second derivative of X-ray transmission intensity through a shell to locate the points of inflection in the transmission intensity υs radius plot which denote the layer interfaces with the accuracy of about 0.2 pixels. (authors)