For measuring the three-dimensional shape of an object of measurement using a
phase shift method, a three-dimensional measuring instrument is provided which
is capable of shortening the measurement time. A printed state inspection device
1 includes a table for placing a printed circuit board K printed with cream
solder H, an illumination device 3 for illuminating three sine wave light
component patterns with different phases on the surface of printed circuit board
K, a CCD camera 4 for picking-up images of the illuminated part of the printed
circuit board K, a white light illumination unit L for illuminating a white light
on the surface of printed circuit board K, and a laser pointer for measuring the
standard height. A control device 7 determines the existing area of the
cream solder H from the image data obtained by the illumination of the white light,
and calculates the height of the cream solder H from the image data obtained by
the illumination device 3 by using a phase shift method.