An ultraviolet photon counting imaging detector system based on Ge induction readout mode

Photon counting imaging technology has been widely used in nuclear radiation detection, space environment detection, astronomy observation, nuclear physics and ultraweak bioluminescence. The structure and operating principles of ultraviolet photon counting imaging systems based on direct electron collection mode and induction readout mode are introduced, but there are more advantages with the induction readout mode. The gain characteristic, resolution, linearity and count rate of a system based on induction mode are evaluated. The dark count pulse height distribution curves shift towards higher pulse height, and the dark count rate increases as the voltage increases. The pulse height distribution curves with light incidence also indicate that the count rate with higher pulse height increases as the voltage increases. The resolution test results show that the system resolution is better than 100 μm along the Y direction and better than 80 μm in some areas. The nonlinearity in both directions is less than 5% in a Φ35 mm area. The system resolution at a low count rate is better than that at a high count rate.