This disclosure relates to directional intensity smearing for high throughput soft X-ray (SXR) metrology. In SXR metrology systems, a pixelated detector (e.g. a camera) may be employed to measure diffracted light from a sample. The sample is typically 1D or 2D periodic and the SXR beam has relatively low divergence e.g. ～0.5-3 mrad). giving rise to diffraction orders that are detected on only a few pixels. In addition, to achieve a high detection numerical aperture (NA). and therefore to support measurements of small pitches, the detector is generally made as large as possible (or multiple tiled detectors may be used) and placed as close as possible to the sample (typically determined by the distance at which far field diffraction is achieved). The result is that the vast majority of the pixels on the detector sec no signal, while a few pixels sec extremely high flux.
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