Fixed optical grating, moving optical grating and photoelectric encoder

Abstract

The invention provides a fixed optical grating which is applied to a photoelectric encoder. The fixed optical grating comprises a fixed optical grating absolute code channels and fixed optical grating subdividing codes channels; the fixed optical grating absolute code channels and the fixed optical grating subdividing code channels are concentrically arranged; the number of the fixed optical grating absolute code channels is M, wherein M is an integer greater than or equal to 2; the fixed optical grating subdividing codes channels include standard subdivision code channels; the light transmission area of the standard subdivision code channels changes in the form of the positive half period of a trigonometric function with the rotation 360 degrees / 2<M> of a moving optical grating; and interpolation is performed on the trigonometric function, so that the rotation angle of the moving optical grating can be subdivided. According to the fixed optical grating provided by the embodiments of the invention, the standard subdivision code channels are arranged on the fixed optical grating, so that the light transmission area of the standard subdivision code channels changes in the form of the positive half period of the trigonometric function with the rotation of the moving optical grating, and therefore, electric signals which have been subjected to photovoltaic conversion correspondingly change in the form of the positive half period of a trigonometric function; and since the electric signals having sine features are adopted as source signals for electronic subdivision, the accuracy of the photoelectric encoder can be effectively improved.

Description

technical field [0001] The embodiment of the present invention relates to the field of photoelectric digital detection, in particular to a fixed grating, a moving grating and a photoelectric encoder. Background technique [0002] The photoelectric encoder is a kind of angle measuring equipment integrating light, mechanics and electricity. It converts optical signals into electrical signals through mechanical structure and signal processing circuit, so as to realize the direct or direct measurement of various physical quantities such as diagonal displacement, position and speed. indirect measurement. Photoelectric encoders include incremental photoelectric encoders, absolute photoelectric encoders and hybrid photoelectric encoders. [0003] In the absolute photoelectric encoder, the absolute encoding of the moving grating can realize that the encoding of each angle within one circle is unique. The resolution and analytical scale of the photoelectric encoder are determined b...

AI Technical Summary

Problems solved by technology

The resolution and analytical scale of the photoelectric encoder are determined by the open or dark lines of the fixed grating, but due to the limitation of the area and processing technology of the fixed grating, the open or dark lines of the grating cannot be increased without limit, that is, the photoelectric encoder The resolution and analytical indexing can only be within a certain range, and the precision is low, which cannot meet the needs of precision

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