Device and method of detecting polished quartz wafer shallow scratch

The invention discloses a device and a method of detecting a polished quartz wafer shallow scratch. The device comprises a material feed cylinder, a wafer taking tray, a positioning module, a wafer taking sucking head, a detection tray, a front detection module, a back detection module, a wafer placing sucking head and a wafer accommodation box, wherein the material feed cylinder is used for scattering polished wafers onto the wafer taking tray based on certain vibration frequency under control of a main procedure, the wafer taking tray is designed to turn by a small angle clockwise and anticlockwise precisely, so as to distribute the polished wafers onto the wafer taking tray uniformly disorderly to be taken up one by one layer, the positioning module comprises a positioning camera, a lens and a light source, is above the wafer taking tray, and is used for positioning and imaging the polished wafer on the wafer taking tray, so as to calculate coordinates of the polished wafer, whereinthe coordinates comprise