Repeat : One horizontal line or raster line of the image is captured in a step and the Carrier Unit or ADF mechanically moves to the next step. The distance moved determines the subscan sampling rate (1/ 300 inch = 300 ppi, 1/600 = 600 ppi). Note Pages load face down on the ADF. The backside optics are in the ADF above the frontside optics, which are in the Carrier Unit, below the glass. 250 Chapter 5 Functional Overview C4265-90907