Workpiece warpage measuring device and warpage measuring method

摘要

PROBLEM TO BE SOLVED: To provide an effective technique to accurately measure a warpage of a tabular work-piece.SOLUTION: A warpage measuring device 1 includes a surface plate 10, an illuminating device 20 for emitting illumination light to the surface plate 10 and a camera 30 for imaging a work-piece W placed on the top surface 11 of the surface plate 10 with a side surface 12 of the surface plate 10 from lateral view points 31, 33. The surface plate 10 includes a first detection surface 13 provided on the side surface 12 to connect to the top surface 11, having a surface width B in a predetermined vertical direction and a second detection surface 14 provided on the side surface 12 to connect to the lower part of the first detection surface 13. The luminance when viewing the first detection surface 13 from the lateral view points 31, 33 is lower than the luminance when viewing the second detection surface 14 from the lateral view points 31, 33 and is lower than the luminance when viewing the work-piece W from the lateral view points 31, 33 in illumination by the illuminating device 20.SELECTED DRAWING: Figure 1