Spatial resolution of gated x-ray pinhole cameras

We have conducted an investigation of the spatial resolution of a new gated x-ray pinhole camera (FXI). The spatial resolution, or its Fourier transform the modulation transfer function (MTF), is critical for quantitative interpretation of recent hydrodynamic instability data taken on the Nova laser. We have taken data corresponding to backlit straight edges, pinholes, and grids, both on the bench and in situ on Nova. For both the pinhole and edge data, the MTF at all wavelengths of interest can be deduced from a single image. Grids are of more limited usefulness, giving the value of the MTF only at the spatial period of the grid. These different techniques for characterizing the MTF of gated x-ray pinhole cameras will be discussed, with results specific to the EXT presented. (C) 1997 American Institute of Physics.