| 摘要 |
According to the present invention, an X-ray detector is disclosed, comprising:
a) a layer of photosensitive material (4);
b) an NxM array of photo-detector diodes (2) arranged in said layer of photosensitive material (4); each of said photo-detector diodes (2) having a bias potential interface (12) and a diode output interface, said bias potential interface (12) of each photo-detector diode (2) being connected to a bias potential (V bias );
c) an NxM array of high gain, low noise readout unit cells (RO), one readout unit cell (RO) for each photo-detector diode (2);
d) each readout unit cell (RO) comprising:
d1) an input interface (IN) connected to said diode output interface, a high-gain voltage amplifying means (PA) comprising an integration capacitor (C fb ),
d2) a first switch (S1) in parallel to the integration capacitor (C fb ),
d3) a sample/hold capacitor (C S ) disposed between a second switch (S2) and third switch (S3), wherein the sample/hold capacitor (C S ) is connectable to an output (OUT) of the high-gain voltage amplifying means (PA) via the second switch (S2) and is connectable to a signal output line (SO) via the third switch (S3);
e) a multiplexing means (MM) comprising a row select and a column select circuit allowing to access each readout cell unit (RO), i.e. to read out the analog signal as actually stored in the sample/hold capacitor (C S ) to a data processing means (DPM) controlling the multiplexing means. |
