An ultrasonic probe which performs a two-dimensional scan is supported by a mount having a thread which is driven back and forth by a screw along a third axis. When a two-dimensional scan is completed in a first plane, a motor drives the mount along a guide to a second plane for the next scan. The separation between the planes being the same as the resolution in scanning within a plane. A housing having a slot with sidewalls is employed to guide the mount in traveling to successive plane locations along its axis. Means for orienting the housing in angular position and a support assembly provide moveable support to the orienting means so that minimal force is required to position the probe relative to the patient. An "auto-scroll" feature permits the operator to interactively pan through multiple, adjacent two-dimensional planes at programmable speeds and displacements along a third axis. A foot switch provides for hands-free bi-directional scrolling in a "user scroll" mode

An inclination adjusting device for a light controlling element used in an optical scanner of a laser printer etc. includes an ultrasonic motor including a stator with a piezoelectric element and a rotor rotated by a traveling wave generated in the stator and a light controlling element having an inclination adjusted according to rotation of the rotor.

An intraluminal imaging catheter system for viewing segments of vessels downstream of the catheter itself is provided. The catheter system incorporates an ultrasonic transducer pivotally mounted adjacent the catheter's distal end. A flexible drive means disposed within a flexible tubular member adapted for insertion into the vessel causes the transducer to pivot back and forth to scan a segment of the vessel. Optionally, the forward viewing catheter system of the present invention may be combined with a work element such as a biopsy tool or other device for use in conjunction with the imaging capability.