For the last several years, the linear array x-ray detector for x-ray imaging with gallium\narsenide direct conversion sensitive elements has been developed and tested at\nthe Institute for High Energy Physics. The array consists of 16 sensitive modules.\nEach module has 128 gallium arsenide (GaAs) sensitive elements with 200 �¼m pitch.\nCurrent article describes two key program procedures of initial dark current compensation\nof each sensitive element in the linear array, and sensitivity adjustment for\nalignment of strip pattern in the raw image data. As a part of evaluation process a\nmodular transfer function (MTF) was measured with the slanted sharp-edge object\nunder RQA5 technique as it described in the International Electrotechnical Commission\n62220-1 standard (high voltage 70 kVp, additional aluminium filter 21 mm) for\nimages with compensated dark currents and adjusted sensitivity of detector elements.\nThe 10% level of the calculated MTF function has spatial resolution within 2 - 3 pair\nof lines per mm for both vertical and horizontal orientation.
Loading....