1, 2,　 3 : the X-, Y-, Z- axes 4 : the print-head, containing pens 5 : microscope glass slides are placed on the slide station 6 : samples are prepared and arrayed from 96-well sample plates 7, 8 : the pins are cleaned between sample acquisitions at the washing 　　　　　　　　 (7) and drying (8) stations.