Other

Bruker Axs Gmbh

Gregory A Wachter

Roger David Durst

Joerg Kaercher

John L Chambers

Tianqing He

Roger Durst

John Chambers

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.

X-ray detector operable in a mixed photon-counting/analog output mode

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.

Method for correcting timing skew in X-ray data read out of an X-ray detector in a rolling shutter mode

Readout noise for each pixel in a CMOS Active Pixel Sensor is reduced by a five step process in which the pixel charge data from the sensor is non-destructively sampled at a plurality of times during a sensor frame time period and corrected for gain variation and nonlinearity. Then fixed pattern and dark current noise is estimated and subtracted from the corrected pixel charge data. Next, reset noise is estimated and subtracted from the pixel charge data. In step four, a model function of charge versus time is fit to the corrected pixel charge data samples. Finally, the fitted model function is evaluated at frame boundary times.

Multiply-sampled CMOS sensor for X-ray diffraction measurements with corrections for non-ideal sensor behavior

Growing community of inventors

Sun Prairie, WI, United States of America

Gregory A Wachter