journal menu
![[Figure 4]](ge5117fig4mag.jpg)
|
|
Figure 4
Results of a Huygens–Fresnel calculation assuming a generic crystal 10 µm wide with 100 reflecting atomic planes spaced 5 Å apart from each other, and with 1000 atomic source points per plane. The wavelength of the radiation was taken to be 5 Å as well, and the distance between crystal face and point of observation of the reflected wave was 0.5 m. This two-dimensional block of source points was taken to be illuminated by plane waves in phase as though the Bragg diffraction condition was effectively satisfied. As in the case of an aperture of the same width, the reflected wave has a well defined lateral dimension which at 0.5 m from its source has a uniform wavefront (to within one wavelength) over a lateral extent of approximately 22 µm – similar to that produced by the single aperture of the same width. On the left is a plot of intensity versus position on a perpendicular detection plane a distance 0.5 m away from the crystal. The horizontal axis of the wave amplitude plot on the right is along the mean direction of propagation, covering a distance of approximately five wavelengths up to the detection plane at 0.5 m at the right terminus. The vertical axis is along a perpendicular direction, and the degree of shading indicates the relative amplitude of the reflected wave. |
![[Figure 4]](ge5117fig4.jpg)
 | JOURNAL OF APPLIED CRYSTALLOGRAPHY |
ISSN: 1600-5767
access
