摘要:
A detector for a small-angle x-ray diffraction system uses curved readout strips shaped to correspond to the expected intensity distribution of x-rays scattered by the system. This expected intensity distribution may be a series of concentric circles, and each of the strips has a shape that approximates a section of an annulus. The strips may be positioned on a substrate such that a center of curvature of the curved strips is located along an edge of a readout region within which the strips are located or, alternatively, at a geometric center of the readout region. The detector may have a signal readout system that uses a delay line or, alternatively, a multichannel readout system. The detector may make use of electron generation via interaction of the diffracted x-ray beam with a gas in a gas chamber, or through interaction of the diffracted beam with a semiconductor material.
摘要:
A detector for a small-angle x-ray diffraction system uses curved readout strips shaped to correspond to the expected intensity distribution of x-rays scattered by the system. This expected intensity distribution may be a series of concentric circles, and each of the strips has a shape that approximates a section of an annulus. The strips may be positioned on a substrate such that a center of curvature of the curved strips is located along an edge of a readout region within which the strips are located or, alternatively, at a geometric center of the readout region. The detector may have a signal readout system that uses a delay line or, alternatively, a multichannel readout system. The detector may make use of electron generation via interaction of the diffracted x-ray beam with a gas in a gas chamber, or through interaction of the diffracted beam with a semiconductor material.
摘要:
A method for X-ray detection using a charge-integrating X-ray detector including a photodetector array of pixels, each of which converts incident radiation into accumulated charge during an X-ray exposure, is provided. The method includes, for each pixel, reading out the accumulated charge from the pixel and determining an X-ray charge value from the read out accumulated charge. If the X-ray charge value is less than a photon counting threshold, the X-ray charge value is replaced with a quantized charge value representative of an estimated photon count and recording the quantized charge value as a recorded charge value. If, however, the X-ray charge is equal to or greater than the photon counting threshold, the X-charge value is recorded as the recorded charge value. The method allows operating a charge-integrating X-ray detector in a mixed photon-counting/analog output mode.
摘要:
In an X-ray detector operating in a rolling shutter read out mode, by precisely synchronizing sample rotation with the detector readout, the effects of timing skew on the image intensities and angular positions caused by the rolling shutter read out can be compensated by interpolation or calculation, thus allowing the data to be accurately integrated with conventional software. In one embodiment, the reflection intensities are interpolated with respect to time to recreate data that is synchronized to a predetermined time. This interpolated data can then be processed by any conventional integration routine to generate a 3D model of the sample. In another embodiment a 3D integration routine is specially adapted to allow the time- skewed data to be processed directly and generate a 3D model of the sample.