A digital signal processor (DSP)-based position calculation circuit was developed and tested for a beta camera. The previous position calculation circuit which employed flash analog-to-digital (A-D) converters for A-D conversion and ratio calculation produced significant line artifacts in the image due to the differential non-linearity of the A-D converters. The new position calculation circuit uses four A-D converters for A-D conversion of the analog signals from the position sensitive photomultiplier tube (PSPMT). The DSP reads the A-D signals and calculates the ratio of Xa/(Xa + Xb) and Ya/(Ya + Yb) on an event-by-event basis. The DSP also magnifies the image to fit the useful field of view (FOV) and rejects the events out of the FOV. The line artifacts in the image were almost eliminated.
|ジャーナル||Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment|
|出版ステータス||Published - 2000 3月 1|
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