Patent ID: 6019504
Filing Date: 2000-02-01
Classification: G01N

Abstract:
An apparatus for photothermally examining workpiece surfaces, comprising a measuring unit including an exciting beam generator of electromagnetic radiation adapted to direct exciting beams to selected points to be measured on a workpiece surface, and further including detector means adapted to detect heat radiation emitted from the points to be measured and to forward the same to be analyzed, and comprising optical means for splitting the exciting beam into a plurality of partial beams and for directing said partial beams of the exciting beam substantially simultaneously to a plurality of points to be measured arranged in a line on the workpiece surface, wherein the measuring unit is adapted to be moved stepwise with respect to the workpiece surface in a direction parallel to the workpiece but not parallel to the line of points to be measured for directing the partial beams to different lines of the points to be measured on the workpiece surface after elapse of the measurement period.