| 摘要 |
The device, which can be used in particular for measuring the variations in the end part of gun tube (10) with respect to a support, comprises a reflector (12) carried by the object and a light source-detector assembly (16) carried by the support at a location such that the said variations cause the displacement of an image of the source on the detector. In order to measure the variations in orientation about a single direction, the reflector comprises a single dihedron (12) whose edge is perpendicular to the said direction and whose peak angle differs from 90 DEG by a small angle beta and the source comprises at least one pulsed light emitter offset from the detector, in the said direction, by a distance a = 2f beta , where the dihedron consists of two reflecting silvered surfaces and f is the focal length of the collimator, and by a distance a = 2nf beta where the dihedron is a total reflection prism and n is the index of the material forming the prism. <IMAGE> |
