Abstract: In scanning devices used for opto-mechanical processing of a substrate covered with a photo-sensitive material, it is highly desirable to be able to achieve accurate control of the carriage utilized for scanning the substrate. To accomplish this, the carriage is moved along a rectilinear guide by use of a linear motor, preferably under computer control. The linear motor includes a winding which is composed of a number of isolated conductors attached to the rectilinear guide orthogonally to the longitudinal axis of the guide. The winding is connected to the control computer through a controllable current source. The linear motor also includes a solid-state commutator coupled to magnetically propel the carriage in accordance with current supplied to the winding from the controllable current source based on instructions from the control computer.