Incremental encoder scale and its manufacturing method

Abstract

The invention relates to a scale (10) for an incremental encoder, wherein the scale (10) has an incremental track (20) with scattering areas (23) and mirror areas arranged alternately in the longitudinal direction (x) (twenty four). The scattering regions (23) each have at least two rectilinear depressions (26-1, 26-2, 26-3, 26-4, 26-5), which are substantially perpendicular to the incremental track longitudinal direction (x ) are stretched and arranged successively in rows in the longitudinal direction (x) of the incremental track (20) and are configured to reflect incident light diffusely. In contrast, the mirror region ( 24 ) of the incremental track ( 20 ) has a substantially smooth surface, which is designed to mirror incident light. Furthermore, the incremental track (20) also has a pitch (P), which is the sum of the width (B23) of the scattering region (23) and the width (B24) of the specular region (24). In order to optimize the contrast of light scattered by this scale, the scattering area (23) has a width (B23) in the longitudinal direction (x) of the incremental track (20), which is less than half the pitch (P), where the scattering area ( Two of the rectilinear depressions (26-1, 26-2, 26-3, 26-4, 26-5) of 23) are arranged on opposite sides (As1, As2) of the scattering region (23) and The width (B23) of the scattering zone (23) in the longitudinal direction (x) of the incremental track (20) is limited.

Description

technical field [0001] The invention relates to a scale for an incremental encoder. Furthermore, the invention relates to a method for applying such a scale to a metal surface. [0002] The invention therefore relates in particular to a scale having at least one incremental track with alternatingly arranged scattering and mirror regions in the longitudinal direction. The scattering regions of at least one incremental track each have a plurality of substantially circular depressions, which are designed to diffusely reflect incident light. In contrast, the specular region of at least one incremental track is a substantially smooth surface configured to specularly reflect incident light. Furthermore, the scale has a pitch which is the sum of the width of the scattering region and the width of the specular region. In other words, the scale is periodic and the period length of the scale is defined as the pitch. Background technique [0003] With regard to the pitch, it is als...

AI Technical Summary

Problems solved by technology

[0009] However, the scales known from the prior art have the disadvantage that the sensor signals detected by the sensor device often have only a very small contrast, which means that the sensor device generates the sensor signal by sampling the diffuse and specular regions respectively. , while the sensor signal generated by sampling the diffuse region and the sensor signal generated by sampling the specular region do not differ much in scale and therefore have a small proportional difference (contrast)

This in turn can lead to insufficient discrimination of the individual scattering regions and insufficient knowledge of the displacement of the sensor device relative to the scale

Furthermore, the scales known from the prior art also have the problem that the sensor signals detected by reflections at the scales have very little interpolability

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