| The principle of Faraday cage was used in this dissertation, the signals of high-energy EB were collected, and we used the principle of the magnetic coil driving the electronic beam current to deal with the high-velocity scanning which arrived the purpose of EB ordinally pass through the Faraday hole. Then the sensor detection of EB's energy density distribution would be detected.The high voltage EB transducing and detecting system which could detect the energy density distribution rule of 60-150kV,5-100mA EB was designed. The sensing unit of EB Faraday cage, beam magnetic coil, the high degree of accuracy EB amplifying circuit and the card of high-speed data collection were constituted this system.The direction from scaning EB to Faraday cage is X direction, and stepping on the Faraday cage is Y direction.The relation of electric current and magnetic field in X and Y deflect orientations was obtained by the basis of testing deflecting coil which was manufactured in Aachen University. The 12 pole terminal deflecting coil, in which the winding of everyone was 87 and the design flow was 0.27mm, was counted by EB scanning route and pace of 20μm.The transducer amplifying circuit and the micro differential signal amplifying circuit were designed which have the features of controlled magnification by EB enters into Faraday cage. The two circuits are also applicable the amplifying of the smallscreen. At the same time, the 3-level active low-pass filter circuit was designed using EWB simulation software to imitate the micro differential signal amplifying circuit.100 points should be collected in the cross section of EB which had the 2mm diameter during the process of X orientation scanning by the frequency of 5KHz. The requirement of compulsory minimum speed collecting card is 25MHz and PCI-1714 would arrive to the speed of 30MHz of which resolving capability is 12. The collection of high-speed and high degree of accuracy would be achieved in the end. |
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