An absolute encoder includes a scale having a sequence of marks, a detector configured to detect a signal corresponding to a plurality of marks of the scale, and a processor configured to obtain an absolute position corresponding to the signal. The processor is configured to select code sequences, from a group of code sequences corresponding to absolute positions, as a candidate group for a code sequence corresponding to the signal, and to select the code sequence corresponding to the signal from the candidate group.

A magnetic sensor is provided with first and second magnetoresistive effect elements that can detect an external magnetic field. The first and second magnetoresistive effect elements are a plurality of layers of multilayer body including free layers where their magnetization directions vary due to the external magnetic field. Shapes of the first and second magnetoresistive effect elements viewed from the upper side in the lamination direction are different from each other. The first magnetoresistive effect element has a shape that can increase a slope of an output of the first magnetoresistive effect element relative to the change of the external magnetic field. The second magnetoresistive effect element has a shape that can decrease a slope of an output of the second magnetoresistive effect element relative to the change of the external magnetic field compared to the slope of the output of the first magnetoresistive effect element.

An absolute position measurement system includes a multipole magnet comprising alternating magnetic poles extending along a multipole extension direction, the alternating magnetic poles generating a magnetic field. A magnetic sensor includes a first sensor element arrangement configured to generate a first signal in response to a first magnetic field component and a second sensor element arrangement configured to generate a second signal in response to a second magnetic field component. The absolute position measurement system is configured, as a position of the magnetic sensor relative to the multipole magnet changes, to generate a first oscillating sensor signal with decreasing first signal amplitude and to generate a second oscillating sensor signal with decreasing second signal amplitude based on the first and second signals. A processing circuit is configured to calculate an absolute position of the magnetic sensor based on the first oscillating sensor signal and the second oscillating sensor signal.

An inductive angle sensor includes an exciter coil, an oscillator circuit, a plurality of receiver coils, an evaluation circuit evaluating a plurality of signals induced in the receiver coils, and a coupling element that is movable and influences a strength of an inductive coupling between the exciter coil and the receiver coils. The coupling element has a first encoder element and a second encoder element. The coupling element has a third encoder element formed as a conducting extension with an asymmetric geometry. The asymmetric geometry influences the strength of the inductive coupling between the exciter coil and the receiver coils only in a part of a plurality of periodically repeating loop structures of the receiver coils.

An absolute encoder configured to, when a rotation range of a measurement target member is limited by a brake mechanism, generate an AB-phase signal and a Z-phase signal for calculating a rotation angle of the measurement target member. The absolute encoder includes a brake mechanism, a plurality of Z-phase-signal-detection-target portions each having a Z-phase-signal-rise-detection-target portion and a Z-phase-signal-fall-detection-target portion, a plurality of AB-phase-signal-detection-target portions each located between a Z-phase-signal-rise-detection-target portion and a Z-phase-signal-fall-detection-target portion that are adjacent to each other in a circumferential direction, to thereby form a plurality of restriction ranges each including at least one of the Z-phase-signal-rise-detection-target portions and at least one of the Z-phase-signal-fall-detection-target portions. An interval in the circumferential direction between a Z-phase-signal-rise-detection-target portion and a Z-phase-signal-fall-detection-target portion that are adjacent to each other in the circumferential direction is different among the plurality of restriction ranges.

An encoder system has a reading head and a material measure. The reading head haa at least one first position sensor and at least one second position sensor. The position sensors are positioned at a fixed distance from one another in a reading direction. The material measure has a longitudinal direction and a transverse direction. The material measure has a first code segment in the longitudinal direction with a first absolutely coded code track. The reading head and the material measure are positioned relative to one another in such a way that the reading direction corresponds to the longitudinal direction. The reading head and the material measure are movable relative to one another in the reading direction. A first sensor position on the material measure can be detected by the first position sensor and a second sensor position can be detected on the material measure by the second position sensor.

System for measuring the position of a mechanical member, which comprises an optical detection system and a positioning track arranged on two mechanical members of a mechanical device. The positioning track is provided with a succession of multiple sectors, each of which comprises a first delimitation section and a second delimitation section spaced from each other, and a first identification section and a second identification section which are provided with a different optical contrast with respect to the first delimitation section and to the second delimitation section. In each sector, the first identification section is delimited between the first delimitation section and the second delimitation section. In addition, the length of the identification sections of each sector is different from the length of the identification sections of each other sector of the succession, so as to unequivocally identify the corresponding sector.

A magnetic sensor is provided with first and second magnetoresistive effect elements that can detect an external magnetic field. The first and second magnetoresistive effect elements are a plurality of layers of multilayer body including free layers where their magnetization directions vary due to the external magnetic field. Shapes of the first and second magnetoresistive effect elements viewed from the upper side in the lamination direction are different from each other. The first magnetoresistive effect element has a shape that can increase a slope of an output of the first magnetoresistive effect element relative to the change of the external magnetic field. The second magnetoresistive effect element has a shape that can decrease a slope of an output of the second magnetoresistive effect element relative to the change of the external magnetic field compared to the slope of the output of the first magnetoresistive effect element.

In a length or position measuring system which has an at least locally substantially linear measuring gauge and at least one sensor to be moved relative to the measuring gauge, wherein the measuring gauge includes an incremental track and at least one absolute track and wherein the incremental track and the at least one absolute track have poles arranged in the longitudinal direction of the measuring gauge, the poles of the at least one absolute track form at least two regions in the sensor with different field strengths or signal amplitudes.

A scale device includes a scale main body having at least two incremental tracks, at least two or more incremental signal detection heads for detecting incremental signals from the incremental tracks, and an operation processing unit that generates, based upon detection outputs by the two or more incremental signal detection heads, relative positional information in a measuring direction of a measuring axis and parallel movement amount information in a direction orthogonal to the measuring direction.