IsCMOS camera
An IsCMOS camera is integrated with a front taper, an image intensifier which amplifies and slightly delays the signals of the fibers, a rear taper and a sCMOS chip.
A 3-D shower event is then converted by the camera collecting 7500 WLS fibers into a 2-D image, which includes variable number of light faculae with variable sizes and grayscales. Low resistance and Atomic Layer Deposition coating for the Micro Channel Plate in the image intensifier are essential for a larg dynamic range and a long lifetime, respectively. The decay time of phosphor screeen in the image intensifier ranges from 20 to 200 microseconds with limits from a trigger delay time of around 200 ns and short dead time. The pixel size of the sCMOS chip is around 40 micrometer for a large Full Well Charge and also fast readout speed. A dead time within 1.2 ms, including an exposure time of 0.2 ms and a charge readout of 1 ms, is foreseen. The energy deposited in one crystal is obtained by analyzing the grayscales of the facula formed by about 30 corresponding CMOS pixels.