Measuring device for angular position of object - has objective in two parts, one between reticule and first mirror, and other between second mirror and image plane

摘要

The device has an objective for projection of an image of cross-hairs in a reticule on an image plane. There are photoelectric transducers in the image plane and a deflection system with two plane mirrors, one of which is in the path of rays from the reticule. The light beam is deflected to the second mirror. The first mirror is rotatable about an axis in a plane normal to the direct and deflected beams, and parallel to a bisectrix of the angle between the cross-hairs. The second mirror is mounted on the tested object. The objective (15) consists of two parts (17, 18), the first (17) between the reticule (16) and the first mirror (23), and the second (18) between the second mirror (24) and the image plane (19).