| 摘要 |
PURPOSE:To achieve a higher speed and a simpler circuitry by simultaneous operation of an A/D conversion and normalization with the same circuit. CONSTITUTION:Light detectors 2 such as numerous photoelectronic multipliers are arranged in a two-dimensional manner on the back of a scintilator 1 comprising a single NaI (Tl) crystal and coupled optically. When radiation such as gamma ray enters the scintilator, light is generated in proportion to the energy thereof and caught with several of the light detectors 2, where the light detectors 2 located closer to the position of the light generated produce larger outputs. The outputs of the light detectors 2 are inputted into a weighted addition circuits 4 and 5 and an addition circuit 6 in directions of X and Y via a pre-amplifier 3. As known by a gamma type scintilation camera, the weighted addition circuits 4 and 5 obtain signals X and Y for the position of light generated in the directions of X and Y utilizing the fact that the light detectors 2 located closer to the position produce larger outputs. The signals X and Y integrated are inputted into A/D converters 10 and 11. |
