Groove shape measuring method and groove shape measuring apparatus

A groove shape measuring method for measuring a shape of a processing groove formed on a workpiece by a processing apparatus, the groove shape measuring method comprising:

• a setting step of dividing the processing groove into measurement regions with a predetermined pitch along a longitudinal direction of the processing groove and further setting N number of sub-measurement regions along the longitudinal direction in each of the measurement regions, wherein N is a natural number of two or more;
• a coordinate data acquisition step of acquiring coordinate data representing the shape of the processing groove in M-th sub-measurement regions in the respective measurement regions, wherein M is any natural number from 1 to N;
• a cross-sectional profile generation step of generating a cross-sectional profile of the processing groove by projecting coordinate data corresponding to the M-th sub-measurement regions acquired in the coordinate data acquisition step, onto a two-dimensional plane;
• and
• a coordinate data measurement step of measuring the coordinate data on the processing groove,
• wherein in the coordinate data acquisition step, the coordinate data corresponding to the M-th sub-measurement regions in the respective measurement regions are acquired from the coordinate data previously measured in the coordinate data measurement step.