Design and construction of a berreman-type point-focusing X-ray monochromator for use in low-angle scattering studies

• Published in: Journal of ultrastructure research Vol. 9; no. 5; pp. 419 - 444
• Main Authors: Dibble, William E., Dumond, Jesse W.M.
• Format: Journal Article
• Language: English
• Published: United States Elsevier B.V 01.12.1963
• Subjects: Equipment and Supplies; Old Medline; Radiology; Scattering, Small Angle; Technology; Technology, Radiologic; X-Rays; TECHNOLOGY, RADIOLOGIC; EQUIPMENT AND SUPPLIES
• ISSN: 0022-5320; 1878-2345
• DOI: 10.1016/S0022-5320(63)80076-3

The design and construction of a point-focusing Berreman-type single quartz crystal X-ray monochromator for low-angle scattering is described. Monochromatization and point focusing of the copper K α 1 line are obtained by Bragg reflection from an appropriately bent 2½ by 2⅜ by 0.015 inch crystal lamina. With a 0.0225 inch aperture defining the size of the X-ray source next to a General Electric CA-7 diffraction tube running at 45 kV and 18 ma, about 3 × 10 9 counts per minute may be put into a 0.025 inch half-width focus, in helium atmosphere. Parasitic scattering from the crystal which competes with scattering from the sample was excluded by using a converging vane collimator, which required coating with lead chloride to prevent low-angle total reflection from the vanes. Sample-to-detector distances of up to 49 cm are obtainable. Keratin and albumin scattering patterns are shown to illustrate the instrument's performance.