Retro-reflective prism assembly

摘要

A retro-reflective prism assembly for use with electronic distance measuring instruments in surveying and other civil engineering applications. The unique structure permits tilting and plunging the assembly without requiring a separate tiltable bracket. A novel housing and sealing arrangement positions and seals the prism for limiting shock and preventing water leakage while obviating any need for coating the rear surfaces of the prism. An eccentric tilting knob simplifies angular tilt setting while a convenient transit knob simplifies azimuth adjustment. Vertical sighting holes in the yoke of the assembly provide for convenient plumbing of the assembly. A uniquely configured dust cover is designed for convenient storage on the back of the prism housing during use of the assembly. Target indicia are applied to both the front and back surfaces of the dust cover to provide a novel target device which may be secured to the face of the prism and to the back of the prism for range targeting with an offset and without an offset, respectively.