@article{oai:repo.qst.go.jp:00081353,
 author = {羽多野, 忠 and 小池, 雅人 and 寺内, 正己 and ピロジコフ, アレキサンダー and 林, 信和 and 笹井, 浩行 and 長野, 哲也 and Masato, Koike and Pirozhkov, Alexander},
 issue = {16},
 journal = {Applied Optics},
 month = {Jun},
 note = {Numerical approach and experimental studies have been performed to evaluate the enhancement of diffraction efficiency of diffraction gratings by overcoating with lanthanum series layers on conventional metal coated laminar-type gratings around B K-emission (183 eV, 6.76 nm). We propose an optical design method with a concept of spectral flux given by collection efficiency and diffraction efficiency. A diffraction grating of small angle of incidence gives an advantage to soft X-ray spectrographs because it collects the emission from the point source in larger solid angle compared to the conventional grazing incidence diffraction gratings. We found that La, La2O3, and LaF3 were promising as overcoating materials on a laminar-type Ni-coated diffraction grating as the results of numerical calculation, and performed experimental study using LaF3 and La/C overcoatings, considering producibility and durability. Diffraction efficiencies of gratings coated with Ni/LaF3 and Ni/La/C were measured by use of a reflectometer at a synchrotron facility. As the results, the observed diffraction efficiencies at 183.4 eV were 29.4 % and 34.3% at the angles of incidence of 85.1° and 84.9° for Ni/LaF3 and Ni/La/C gratings, respectively.},
 pages = {4993--4999},
 title = {Design and experimental evaluation of enhanced diffraction efficiency of lanthanum-based material coated laminar-type gratings in boron K-emission region},
 volume = {60},
 year = {2021}
}