A three-dimensional measurement system , comprising: a projector configured to project patterned light onto a target object ; a first camera configured to image the target object ; a second camera configured to image the target object from a viewpoint different from the first camera ; and an image processor configured to process a first image received from the first camera and a second image received from the second camera to obtain three-dimensional information about the target object , the image processor including a first measurer configured to obtain first depth information using the first image with a spatially encoded pattern technique, a defined configured to define a search range for a corresponding point for stereo matching based on parallax between the first image and the second image predicted from the first depth information, and a second measurer configured to obtain second depth information by performing stereo matching for the defined search range using the first image and the second image, the second depth information having a higher spatial resolution than the first depth information, wherein the patterned light has a combined pattern combining a spatially encoded pattern and a random pattern , the spatially encoded pattern includes a plurality of unit elements arranged regularly, each of the plurality of unit elements is an area corresponding to a depth value, and the random pattern includes a plurality of random pieces arranged randomly. a projector configured to project patterned light onto a target object ; a first camera configured to image the target object ; a second camera configured to image the target object from a viewpoint different from the first camera ; and an image processor configured to process a first image received from the first camera and a second image received from the second camera to obtain three-dimensional information about the target object , the image processor including a first measurer configured to obtain first depth information using the first image with a spatially encoded pattern technique, a defined configured to define a search range for a corresponding point for stereo matching based on parallax between the first image and the second image predicted from the first depth information, and a second measurer configured to obtain second depth information by performing stereo matching for the defined search range using the first image and the second image, the second depth information having a higher spatial resolution than the first depth information, a first measurer configured to obtain first depth information using the first image with a spatially encoded pattern technique, a defined configured to define a search range for a corresponding point for stereo matching based on parallax between the first image and the second image predicted from the first depth information, and a second measurer configured to obtain second depth information by performing stereo matching for the defined search range using the first image and the second image, the second depth information having a higher spatial resolution than the first depth information, wherein the patterned light has a combined pattern combining a spatially encoded pattern and a random pattern , the spatially encoded pattern includes a plurality of unit elements arranged regularly, each of the plurality of unit elements is an area corresponding to a depth value, and the random pattern includes a plurality of random pieces arranged randomly. <EOS>