To provide a small-sized device for performing phase control of pattern light with a simple mechanism, while minimizing the number of mass patterns irradiating the pattern light.

In this device, periodic pattern light is projected to a measuring object, while being translated in the base line 20 direction, in the base line 20 direction formed by a plurality of irradiation light sources and an imaging lens 13 for imaging reflected light on a CCD 14 by a pattern projection method, and a light distribution reflected by the measuring object is taken into the CCD 14, and the three-dimensional shape of the measuring object is measured from the light distribution based on the principle of triangulation. In the device, the plurality of irradiation light sources are arranged at prescribed intervals on the base line 20. The device is equipped with one mask 11 for forming a mask pattern, transmitting or reflecting light irradiated from the irradiation light source, and generating the pattern light, and a driver 15 and a PC 17 for controlling lighting of the plurality of irradiation light sources.