摘要 |
<p>A gamma ray camera A includes a crystal array S which includes a plurality of pixels 4 each of which outputs a pixel signal in response to receiving a gamma ray. A first circuit (6, 8, 10, 12, 14 and 22) outputs for each pixel 4 of the crystal array S, when a pixel signal output by the pixel 4 has a predetermined relation to a reference signal, a threshold signal related to the position of the pixel 4 in the crystal array S. A second circuit (18, 20, 24, 26, 28, 30 and 32) outputs a counter value for each pixel signal having a predetermined relation to its threshold signal. Lastly, a third circuit 34 accumulates for each pixel 4 of the crystal array S a count of the counter values output by the second circuit (18, 20, 24, 26, 28, 30 and 32) for the pixel 4.</p> |