ApplicationNo. 06/805850 filed on 12/05/1985
US Classes:250/231.14, Incremental shaft readers; i.e., with means to generate increments of angular shaft rotation250/237G, Gratings (moire fringes)250/252.1, CALIBRATION OR STANDARDIZATION METHODS356/401With registration indicia (e.g., scale)
ExaminersPrimary: Nelms, David C.
Assistant: Ruoff, Jessica L.
Attorney, Agent or Firm
International ClassesG01D 5/347 (20060101)
G01D 5/26 (20060101)
Foreign Application Priority Data1984-12-05 AT
AbstractAn optoelectronic incremental measuring system for measuring lengths or angles comprises a scale member provided with an incremental scale and a scanning unit, which is adjustable along the scale and comprises scanning grids, which are spaced apart by an integral multiple and a fractional part of a scale increment, a plurality of optoelectronic receivers associated with respective ones of such grids, and a plurality of light-emitting diodes, which are associated with the respective grids and adapted to illuminate the associated receiver via the scale and the associated scanning grid. In such a system a movement of the scanning unit and the scale relative to each other will cause the receivers to generate phase-displaced sine signals having periods in a number depending on the number of scale increments traversed by the scanning unit. The signals generated by the receivers can be adjusted relative to each other in amplitude and phase because the positions of the light-emitting diodes are individually adjustable.
Field of SearchGratings (moire fringes)