<title>Development of multilayer coated gratings for high-energy x-ray spectroscopy</title>

The multilayer coated grating for high energy x-ray spectroscopy above 6 keV was developed. We study the grating optics for high energy region using multilayer. We coated the laminar type grating, groove density/mm and depth of groove is 40 nm, with Pt/C multilayer, number of layer pairs is 10 and periodic length is 4.8 nm. We measured this gratings using the x-ray beam-line Nagoya University with the x-ray CCD system. The efficiency at the first order of grating was about 30 percent at the energy of Cu-K(alpha) with energy resolution of 128.