AbstractThis paper describes a method to determine the 3‐D position and orientation of a plane‐like object. The system first extracts edges of the plane‐like object and its shadow cast on a working table by an ideal point light source. Utilizing the shadow informaton effectively, it estimates the 3‐D positions of several boundary points, from which the position and orientation of the plane‐like object are then determined. An application of this method, measurement of the 3‐D position, and orientation of a printed circuit board, is presented. The errors in measuring the position and orientation are about 1% of the size of sight and 4 degrees, respectively. The result is sufficient for a robot hand to manipulate the printed ci