Patent ID: 7643159

Claim:
A three-dimensional shape measuring method, comprising: preparing a light projector for projecting light toward a measurement object, and a light receiver having a light receiving surface; in conjunction with performing a light projecting/receiving operation of receiving the light projected on a surface of the measurement object and reflected onto the light receiving surface for a predetermined number of cycles and while changing a projecting direction of the light, setting a light receiving time in each of the cycles with respect to each of a plurality of light receiving areas constituting the light receiving surface; acquiring light receiving data in the each of the cycles by performing the light projecting/receiving operations utilizing the light receiving time set for each of the cycles; converting the light receiving data obtained in the each of the cycles into an output value, said output value being standardized with respect to the light receiving time in the each of the cycles if the light receiving times set in the light receiving time setting operation are different in the cycles; acquiring a projection timing at which a light receiving amount of each of the light receiving areas is maximum by using a center timing in a light receiving period in the each of the cycles and the output value for each of the cycles; acquiring a position, in a predetermined three-dimensional coordinate system, of each measurement point on the surface of the measurement object, based on a relation between the projecting direction of the light at each of the projection timings acquired in the projection timing acquisition operation and an incident direction of the light reflected onto the light receiving surface; and deriving a three-dimensional shape of the measurement object based on the acquired positions in the three-dimensional coordinate system.