This on-the-fly scanning control system is for the x-ray nanoprobe endstation at Taiwan Photon Source(TPS) and built base-on the high speed Hardware (H/W), high throughput data stream and multi-channel control interfaces. The main idea is to tag each data with information of time and position, which generates by circuit and laser interferometer. The data is then processed by a computer to be analyzed and visualized.
By using high speed FPGA with embedded processer to process the input and output data which includes the DAC, ADC, Gigabit Ethernet (GbE), X-ray fluorescence (XRF) and laser interferometer control interfaces. Three DAC control the X,Y and Z axes of the flexure stage, four ADCs and sensor interfaces gather the data and packet it into data packet. GbE send data back to computer to do image processing then reconstruct the scanning image. The numerous data not only for rebuild the image but also good for information analysis. Including the vibration, time slide analysis.
Our demo system is built by an e-beam source, flexure stage and laser interferometer. The current maximum scanning speed is up to 5 lines/sec which is limited by the mechanical, the sample rate can be as high as 20M samples/sec which limited by laser interferometer, and the maximum data rate is close to 100M bytes/sec which is limited by the GbE. Interferometer information combine with position data in data packet, makes easy for data analysis and also for image stitching. The system is going to commission on beamline at March, 2017. The commission result for this system will be presented.
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