Abstract: The present invention consists in a three-dimensional vision system comprising a three-dimensional vision sensor which projects slit-like light on an object to-be-handled and which reads out a resulting slit image, an image input portion which controls the slit-like light to be lit up and put out and also controls the read-out of the slit image and which performs extraction processing of differential signals as to image signals read out, and an image processor which performs required controls concerning said image input portion and which processes image data of said image input portion; an image with the projected slit-like light and an image without it being sequentially sampled on an identical scanning line of the read-out image so as to obtain the differential image between them, thereby to extract a light segmentation line based on the projected slit-like light.

Abstract: A position error correcting method and apparatus suitable for operating an industrial robot with high accuracy, in which, after the industrial robot disposed on a working site is moved according to position command values, the moved position of a measurement point on the industrial robot is measured three-dimensionally, and a position error of the industrial robot between the robot coordinate system relating to the operation of the industrial robot and the absolute coordinate system of the industrial robot on its working site is computed by comparing the measured position values of the measurement point with the position command values. The work program prepared for the operation of the industrial robot is modified on the basis of the computed position error so that the industrial robot can be operated in accordance with the work program from which the source of the position error has been eliminated.