Back Reflection Camera on a Budget.

摘要

The paper presents in detail the means of converting a powder diffraction camera into a Seemann-Bohlin focusing type back-reflection camera without affecting the primary purpose of the instrument. A Seemann-Bohlin focusing camera,or back-reflection camera as it is called,is one in which the photographic film,the x-ray slit and the powder specimen all lie on the circumference of the same circle. By removing the exit collimator of a standard Siemens 2-radian powder camera and taping a sample across the opening, a back reflection pattern will be obtained. The components are described in detail and specifications are provided. Results on a tungsten standard are illustrated showing the conventional mode opposed to the modified true focusing mode. Problem areas are discussed briefly with emphasis on single-coated film and good optics. (Author)