Producing a plane or conical optical reference surface

摘要: Apparatus for producing a plane or conical optical reference surface by deflection of primary light beam provided source, with being deflected rotatable deflecting means. The source is suspended as pendulum and directs the in vertical direction towards exists through cylindrical prism if redeflection to produce desired. flexible means comprising at least two members which are respectively directions perpendicular each other, thereby permitting pendulating any providing also energization may be electrically conductive. A method initially aligning axis shown, where free liquid such mercury used retroreflect beam.