journal menu
![[Figure 1]](yi5093fig1mag.jpg)
|
|
Figure 1
Schematic for the positioning of a plane grating with a staircase profile in the Cartesian laboratory system such that the incident and the off-plane diffracted beam progress in the horizontal x–y plane from right to left. The diffraction takes place in the blaze-maximum condition, i.e. the direction for the diffracted beam corresponds to specular reflection at the top of the stairs. The two half arcs next to the grating refer to the cones with identical opening angle γ on which the incident beam and all diffracted orders will be found. The angle α indicates the orientation angle for the incident beam and for the beam which is specularly reflected at the grating surface, i.e. for the beam diffracted in zeroth order. This angle is referenced with respect to the nominal plane of incidence defined by the dashed lines in the arcs. The angle β refers to the orientation of a beam which is diffracted in blaze maximum. Black squares and parallelograms attached to different positions in the beam trajectories illustrate the respective cross sections of the beam. The grey parallelogram presents the related footprint at the grating. The detached arc at the left indicates how the grating equation (1) ![[link]](../../../../../../logos/arrows/s_arr.gif) will affect the residual divergences of the incident beam upon diffraction into the zeroth and the first diffraction order as explained by Cash (1982) (see text for a more detailed explanation). |
![[Figure 1]](yi5093fig1.jpg)
 | JOURNAL OF SYNCHROTRON RADIATION |
ISSN: 1600-5775
