To photograph the whole of a cutting edge so that it falls in the depth of field of a lens, and thereby to check the whole cutting edge with high accuracy when the cutting edge is inspected using a lens of high magnification.

The whole of a cutting edge can be photographed so that it falls into the depth of field of a lens by photographing the cutting edge not only from the direction of a rotary shaft of a drill, but also from the direction perpendicular to the drill cutting edge face.