SHAPE MEASURING INSTRUMENT

PURPOSE:To measure a shape with high accuracy and to maintain facility of processing work and the handling of the titled instrument by using plural image pickup devices and forming the reference shape from three-dimensional drawing dimensions and further, providing an approach prohibitive area of the image pickup devices. CONSTITUTION:TV cameras 19-22 move in parallel freely in a measuring plane. The approach prohibitive area of the cameras is set in the measuring plane. Then, the cameras 19 and 20 move and attain the approach prohibitive area and a limiter 67 is actuated and horizontal movement is prohibited and a horizontal turning mechanism 69 functions and picks up a work 1 on image from the direction turned by an angle theta from the direction perpendicular to the measuring plane. The cameras 21 and 22 are actuated in the same way by a limiter 68 and a turning mechanism 70. In this way, in case the shape measuring instrument 13 is arranged between an operator and the work 11, operation of a forging press and the instrument 13 is facilitated without interrupting a visual field of the operator by the cameras 19-22. Then, an image with intersecting points 33-36 of optical axes 29-32 with the surface 18 to be measured of the work 11 as a center is obtained.