Leydig, Voit & Mayer, Ltd.
Optical position-measuring device
An optical position-measuring device for sensing a position of two relatively movable objects includes a scale connected to one object and having a measuring graduation. A scanning unit is disposed on the other object and has optical elements. An arrangement and design of the optical elements of the scanning unit results in a scanning beam path in which split and subsequently interfered sub-beams propagate mirror-symmetrically with respect to a plane of symmetry and either impinge on and/or are reflected back from the scale in a V-shape. The plane of symmetry is tilted by a defined tilt angle relative to the scale about an axis of rotation that is oriented parallel to a surface of the scale and extends perpendicular to the graduation direction. The sub-beams that are interfered are deflected at the measuring graduation into symmetric diffraction orders. The sub-beams travel identical optical path lengths between splitting and recombination.
DR. JOHANNES HEIDENHAIN GMBH
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G01D G01B G01D G01D
inventional inventional inventional inventional
Wolfgang Karsten
Holzapfel Saendig