Abstract: Apparatus for measuring the shape of a surface of, for example, a metal strip moving over a support surface comprises a laser operable to direct onto the surface of the moving strip a plurality of light beams. From these laser-generated light beams a plurality of light patterns are produced each of which is scanned across the width of the strip and is spaced from the other light patterns in the direction of strip movement. An array of line-scan cameras extends across the width of the strip and is positioned to view and record the projected light patterns. Recorded data from the camera array is processed in parallel to provide a measure of the shape of the strip surface.

Abstract: The transducer's active elements are a plurality of thin, narrow, piezoelric bars bonded side-by-side to a flexible plate. Electrically, a circuit is coupled across the thickness of each bar or strip to include the bars as a plurality of parallel capacitors. The plate has a fixed length that is maintained during operation. Consequently, piezoelectric length expansions and contractions of the bars are translated into an oscillating bending motion of the bars and the plate for transducing purposes.