Study On Data Acquisition For Single Photon Counting Imaging Detector Based On Micro Channel Plate

Recently, the MCP-based single photon counting imaging detector is increasingly applied in space science. The MCP has high resolution and low noise. In2000, the National Aeronautics and Space Administration (NASA) used the Extreme Ultravio-let Imager in the IMAGE Mission to study the distribution of cold plasma in Earth’s plasmasphere by imaging the distribution of the He+ion through its emission at30.4n-m. In2007, the Japan Aerospace Exploration Agency (JAXA) used Upper-atmosphere and Plasma Imager (UPI) in SELENE mission to research the behavior of the plasma through the images of the magnetosphere and the ionosphere around the Earth. These Extreme Ultraviolet detectors are based on single photon detection technique.All kinds of the MCP-based detectors is analyzed through the research of the present status and development trends at home and abroard in the MCP detectors. All kinds of the position-sensitive anode is researched, making the WSA as the charge-collecting anode. Targeting the feature of the WSA, a charge measurement method based on the WSA is designed. The design includes the front end electronics (FEE) and data acquisition (DAQ). The FEE achieves the integration and shaping for the input charge, and the DAQ is responsible to the trigger, position encoding, imaging and im-age storage. Additionally, the GUI panel is developed on the NI-LABVIEW platform using a graphical language named’G’. The panel is able to program the DAQ system, achieving parameter configuration, global trigger, image readout and so on.Subsequently, a series of electronics tests are carried out, including the front-end and the rear-end test. The results show that the input equivalent noise is less than1fC, having a low gain deviation. The platform based on the photon counting imaging detector is built. For low count rate, the system obtains the resolution of70/im. For high count rate, however, the resolution extremely decreases due to the pulse pile-up. Considering the case, an FPGA-based pulse pile-up rejection is designed, effectively discarding the piled-up pulse.In addition, we have researched the performance of the TGC detector. A TGC simulation signal source based on the TRNG is designed, simultaneously testing the256-channel electronics. The measurement efficiency is further upgraded. we propose a formula evaluating the pros and cons of the TRNG. The innovations of this paper are:1. The features of the MCP-based single photon counting imaging detector are researched, summarizing many factors impacting on the count rate and resolution.2. Targetting the kind of detector, we propose a charge measurement method for the photon counting imaging detector. Moreover, the FEE and DAQ is implemented. After a series of electronics tests, the platform based on photon counting imaging detector is built. For low count rate, a resolution of70μm is obtained.3. Considering the pulse pile-up at high count rate, an FPGA-based pulse pile-up rejection is proposed. The design successfully removes the piled-up pulse, greatly increasing the systematical resolution.