Laue cameras, back-reflection

Fig. 5-1 Combination transmission and back-reflection Laue camera. In this camera the Polaroid cassette (at right) and the cassette for ordinary film (at left) are interchangeable either can be used for transmission or for back reflection. (Courtesy of Blake Industries, Inc.)...

Fig. 5-3 Back-reflection Laue camera. The sectored disc on the front of the cassette would be removed for a Laue photograph the purpose of this disc and of the drive motor at left is described in Sec. 6-9. (Courtesy of Philips Electronic Instruments, Inc.)...

When monochromatic radiation is used to examine a powder specimen in a Laue (flat-film) camera, the result is often called, for no particularly good reason, a pinhole photograph. (There is no general agreement on the name of this method. Klug and Alexander [G.39], for example, call it the monochromatic-pinhole technique. ) Either a transmission or a back-reflection camera may be used. A typical transmission photograph, made of fine-grained aluminum sheet, is shown in Fig. 6-11. 

Lane Camera. This flat-film camera can record both transmission and back-reflection patterns. The principle is illustrated in Figure 14 Figure 15 shows a flat-film pattern. Transmission patterns with polychromatic radiation yield information about the symmetry of a cry.stal (Laue symmetry) or with monochromatic radiation the orientation of the crystallites (preferred orientation, texture) such patterns are recorded, for exitmple. from fibers. Back-reflection patterns permit the nondestructive examination of workpiece.s. 

Fig. 7.1. Laue pin-hole camera. Single crystal is stationary and two flat flxed Aims for recording transmission (possible if the crystal is transparent to X-ray) and back reflection (for large crystals)...

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