Abstract: A sheet feeding mechanism for a digitizing scanner particularly adapted to feed transparent and translucent film sheets provides two pairs of feed rollers each located on an opposing side of the scanner camera's image line. A tray for supporting a feed stack is provided. The tray pivots into and out of engagement with a pick roll at predetermined times during the feed cycle. The pick roll rotates to feed the top sheet of the stack into the feed rollers. The top sheet must climb a curved stripper that resists downstream movement of the next sheets in the stack. A pair of edge sensors are located upstream of the upstream feed rollers and downstream of the downstream feed rollers. The sensors sense, respectively, the trail edge and the lead edge of the sheet, respectively and enable a central processing unit to automatically determine the length of the sheet. The sheet can, thereby, be reversed and scanned fully over its entire length.

Abstract: A system is provided for positioning a substrate having a surface required to be characterized with a contact angle measurement. The system includes a stage which supports the substrate and a dispenser assembly having a dispensing tip through which a liquid droplet having a preselected volume is dispensed onto the surface of the substrate. A first actuating mechanism moves the stage in response to first actuation signals and a second actuating mechanism which changes the vertical spacing between the dispensing tip and the surface of the substrate and dispenses the liquid droplet from the dispenser assembly in response to second actuation signals. A controller is connected to the actuating mechanisms and delivers the first and second actuation signals to the first and second actuating mechanisms, respectively, so as to place the liquid droplet at a predetermined location on the surface of the substrate for performing the contact angle measurement.