Dr. Johannes Heidenhain Gmbh

Heinz Tovar

Johann Oberhauser

Wolfgang Holzapfel

Elmar Josef Mayer

A position measuring instrument including a code carrier having first and second code tracks, each including an identical series of code elements, wherein each of the series of code elements has two subregions with complementary properties. A scanning unit having detectors for scanning code elements, wherein each of the code elements defines one corresponding code word, wherein each of the code words defines an absolute position in the measuring direction, and wherein the detectors form a corresponding scanning signal from each of the two subregions of the series of code elements. An evaluation unit generating one item of code information for each of the series of code elements from each corresponding scanning signal, and forming the corresponding code words from the one item of code information, wherein each of the code words is composed of N and K items of code information from successive code elements of the first and second code tracks, respectively, with N and K being greater than 1.

Position measuring instrument

A position-measuring device includes a code, including a series of code elements arranged one behind the other in a measuring direction, in which at least two consecutive code elements respectively form a code word containing a position information item, and a scanning device having detector elements for reading the at least two code elements of the code that form a code word, and an evaluation device in which the code word having the current position information may be ascertained from the scanning signals of the detector elements. The scanning device and the code are arranged in a moveable manner relative to each other in the measuring direction. Between adjacent code elements, which have identical properties in the transition region, separating elements having complementary properties are inserted.

Position-measuring device

A scale and a position-measuring device include the shifting of reference markings in graduation tracks, offset transversely with respect to the measuring direction, by fractions of the interval of the reference markings within a graduation track. It is thus possible to eliminate, or at least to markedly reduce, negative effects of the disturbance of the periodicity of a graduation track by the reference markings.

Position measuring device including a scale having an integrated reference marking

An optical position measuring system that includes a measuring graduation and a scanning unit that is movable in relation to the measuring graduation in a measuring direction. The scanning unit includes a light source that generates light towards the measuring graduation so that scanning signals result from an interaction of the light with the measuring graduation and an opto-electronic detector arrangement has a plurality of detector element units, whose geometric shape and/or arrangement has been selected in such a way that through them at least a partial filtering of undesired harmonics out of the scanning signals results. The measuring graduation includes an arrangement of graduation areas with different optical properties, which is periodic in the measuring direction and has a periodicity TPM and which has been selected in such a way that through them at least a partial filtering of undesired harmonics out of the scanning signals results.

Optical position measuring system with a detector arrangement and measuring graduation to produce partial filtering of undesired harmonics

An optical position-measuring device is described, that includes a scale and a scanning unit movable relative thereto, a light source, one or more scanning graduations, at least one opto-electronic detector element and a mirror lens arranged downstream of the light source. The mirror lens includes a plane reflector surface and two partial surface areas having different radii of curvature. The beams entering through a first partial surface area impinge on the reflector surface and are reflected from the reflector surface in the direction of the second partial surface area. A collimated beam exists subsequent to exiting the second partial surface area.

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Siegsdorf, Germany

Heinz Tovar