Abstract: A scanning apparatus for the array scanning of information upon a record medium to simultaneously develop a multiplicity of information lines. Scanning is carried out by a reciprocating shuttle traversing the width of the scanning area. The record medium to be scanned is mounted on a platen that undergoes periodic longitudinal advancement through a distance corresponding to the width of the band traced by the scanning array. The platen advances when the shuttle is undergoing its reversal. Precise incrementing of the platen is achieved by the positioning of a reference element during the active scanning segment of the shuttle and then locking the reference element in position. The platen is then quickly advanced into contact with the reference element during the short reversal of time of the shuttle. Springs are used to help reverse the direction of travel of the shuttle at each end of its reciprocating scan.