Patent attributes
A workpiece having an outer peripheral portion rotationally symmetric about a symmetry axis can be inspected with high-accuracy while reducing cycle time of the inspection. In an inspection for each of the workpieces, on the basis of the image of the workpiece acquired by executing a first step of capturing an image of the workpiece while holding the workpiece at a pre-alignment position using a holding table and rotating the workpiece about a rotary axis, a position of the workpiece at the holding table is corrected so as to eliminate misalignment of the symmetry axis with respect to the rotary axis. Thereafter, on the basis of the image acquired by executing a fifth step of capturing an image of the workpiece while rotating the workpiece about the rotary axis at an inspection position, the workpiece is inspected. In the inspection of the workpiece, the fifth step for a previous workpiece of two consecutive workpieces and the first step for a next workpiece are executed in parallel with each other.
