Figure 2
(a) The best meridional focal curves (in various colors) for different meridional object distances rm (associated with the various incidence angles to maintain the ideal spectral resolution) are achieved using the scheme discussed in the text, where the image distance cm is fixed for various rm. (b) The best fitting lines for different rm could be identified and regarded as the actual meridional line of the detector plane, its slope in the principal plane of the grating is plot against rm reflecting the orientation of the detector in space, the detector plane is tilted towards the projection of the diffraction beam for smaller rm (e.g. rm = 500 cm, 1000 cm, where the slope of the fitting line is negative) and tilted away from the diffraction beam for larger rm (e.g. rm = 5000 cm, where the slope is positive). Both (a) and (b) have the same color code. |