Patent ID: 11927435
Assignee: CKD CORPORATION
Field: Measurement (Instruments)
Classification: CPC G | IPC G

Claim 0:
1. A three-dimensional measurement device that performs three-dimensional measurement of a measured object using a phase shift method, the three-dimensional measurement device comprising:
an irradiator that irradiates the measured object with a predetermined light pattern having a light intensity distribution in a fringe shape;
a control device that shifts a phase of the light pattern radiated from the irradiator in N different ways, where N is a natural number of not less than 3; and
an imaging device that takes an image of the measured object irradiated with the light pattern, wherein
the control device executes three-dimensional measurement of the measured object by the phase shift method based on N different image data taken under the light pattern having the phase shifted in the N different ways,
the control device executes the three-dimensional measurement by:
obtaining N luminance values with respect to a predetermined coordinate position on the image data based on the N different image data;
extracting luminance values of not less than two but less than N from among the N luminance values, wherein the extracted luminance values are neither overexposed nor underexposed; and
executing height measurement at the predetermined coordinate position based on the luminance values of not less than two but less than N.