Method and apparatus for extending angular coverage for a scanning two-dimensional X-ray detector

An X-ray diffractometer for performing an X-ray diffraction measurement of a sample comprising:

• an X-ray beam directed at the sample;
• a two-dimensional X-ray detector that detects X-ray energy diffracted by the sample;
• and
• a scanning system that moves the detector in an angular direction along a scanning path about a location of the sample while detecting the diffracted X-ray energy and stores a representation of the detected X-ray energy as a spatial intensity distribution relative to a detection area comprising a cylindrical segment wherein, when the detector is located at an extreme of the scanning path, the position of the detector is maintained while detecting the X-ray energy, and a portion of the X-ray energy being detected that is used to contribute to said representation of the detected X-ray energy is progressively changed along said angular direction.

A method for performing an X-ray diffraction measurement with an X-ray diffractometer having an X-ray beam directed at a sample and a two-dimensional X-ray detector that collects X-ray energy diffracted by the sample, the method comprising:

• performing a scan by collecting said diffracted X-ray energy while moving the detector through a scanning range in an angular direction about a location of the sample at a speed of Δα/Δt, where Δα is an angular distance that corresponds to the distance between adjacent columns of detector pixels perpendicular to the scan direction;
• when the detector is located at an extreme of the scanning range, maintaining the position of the detector and actively collecting said diffracted X-ray energy for a duration of N(Δt), where N is the number of said pixel columns;
• and
• normalizing a measured intensity of the diffracted X-ray energy collected by the detector relative to exposure time.