Device for measuring three dimensional shape

A device for measuring three dimensional shape, the device comprising:

• a first irradiation unit having a first light source for generation of a certain light, and a first grating for transforming light from said first light source into a first light pattern having a stripe-like light intensity distribution, so that the first irradiation unit is capable of irradiating said first light pattern from a first position upon an object to be measured;
• a first grating control unit configured to control shifting or switching of said first grating and causing multiple changes of phase of said first light pattern irradiated from said first irradiation unit;
• a second irradiation unit having a second light source for generation of a certain light, and a second grating for transforming light from said second light source into a second light pattern having a stripe-like light intensity distribution, so that the second irradiation unit is capable of irradiating said second light pattern from a second position upon an object to be measured, said second position being different from said first position;
• a second grating control unit configured to control shifting or switching of said second grating and causing multiple changes of phase of said second light pattern irradiated from said second irradiation unit;
• an imaging unit configured to image reflected light from said object to be measured irradiated by said first light pattern or said second light pattern;
• and an image processing unit configured to perform three dimensional measurement by phase shift method based on multiple acquired sets of image data based on said first light pattern or said second light pattern of multiply varied phases;
• wherein said device for measuring three dimensional shape is configured to perform one of a first imaging operation as imaging processing of a single operation among a multiplicity of imaging operations performed by irradiation of said first light pattern of multiply varied phases, and a second imaging operation as imaging processing of a single operation among a multiplicity of imaging operations performed by irradiation of said second light pattern of multiply varied phases;
• wherein the device is configured to, simultaneous with completion of said first imaging operation, start shifting or switching operation of said first grating relating to said first imaging operation;
• wherein the device is configured to, simultaneous with completion of said second imaging operation, without waiting for completion of said shifting or switching operation of said first grating relating to said first imaging operation, start shifting or switching operation of said second grating relating to said second imaging operation;
• wherein the device is configured to, simultaneous with completion of shifting or switching operation of said first grating relating to said first imaging operation, perform said first imaging operation again;
• and
• wherein time required for said shifting or switching operation of said first grating or said second grating is longer than time required for said first imagings or said second imaging operation.