The Wide Field Survey Telescope (WFST) is a dedicated photometric surveying facility equipped with a 2.5-meter diameter primary mirror, an active optics system, and a mosaic CCD camera with 0.765 gigapixels on the primary focal plane for high quality image capture over a 6.5-square-degree field of view. The mosaic CCD camera is the key device for high precision photometric and high frequency observation and the ‘eye’ of the telescope for deep survey with wide field. The focal plane consists of three kinds of CCD including scientific imaging sensors, wavefront sensors and guiding sensors. In the scientific imaging area, there are 9 back-illuminated full frame scientific CCDs –CCD290-99 from E2V company with pixels of 9K by 9K and pixel size of 10um, which is mosaicked by 3 by 3 with flatness of 20μm PV. The R&D of the camera including the high precision large-scale mosaicking of detectors, detectors’ cryocooling and vacuum sealing, readout and driving with low noise and low power, data acquisition, imaging control, data storage and distribution. Furthermore a camera control system (CCS) was developed at same time.
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