Abstract: An absolute position length measurement type encoder includes: a scale which has an ABS pattern based on a pseudorandom code and forms bright and dark patterns by the ABS pattern; a light-receiving element for receiving the bright and dark patterns; a binarization circuit for dividing a digital signal in accordance with a signal output from the light-receiving element into a mode having high brightness and a mode having lower brightness, carrying out a binarization process by a threshold value where dispersion with regard to the two modes is maximized, and decoding the pseudorandom code by the unit of minimum line width of the ABS pattern from the binarized values; and a position detection circuit for calculating the absolute position of the scale with respect to the light-receiving element by acquiring the correlation between the decoded pseudorandom code and the design value of the pseudorandom code.

Abstract: In an absolute position detection type photoelectric encoder devised so as to detect a pseudorandom pattern disposed on a main scale by means of a plurality of imaging optical systems, assembling of the absolute position detection type photoelectric encoder is facilitated and production cost thereof is reduced by providing: a single light-receiving array element disposed on the imaging surfaces of the imaging optical systems, which incorporates a greater light-receiving array portion in the length measurement direction than the light-receiving range of the respective imaging optical systems; a window signal storing portion for storing a window signal showing a light-receiving range of the respective imaging optical systems; and a window signal comparison portion for obtaining signals corresponding to individual imaging ranges by comparing scanning signals of the light-receiving array element with window signals.

Abstract: The absolute position length measurement type encoder is provided with a scale for forming bright and dark patterns by the ABS pattern based on a pseudorandom code; an edge position detection circuit for obtaining a position, at which an after-differentiated absolute value of a binarized value is locally maximized, for each of the minimum line width zones of the ABS pattern by binarizing a signal from the light-receiving element that receives the bright and dark pattern; a peak position detection circuit for obtaining the peak position from a histogram with respect to the position; a decoding circuit for decoding the pseudorandom code based on the binarized value; an absolute position detection circuit for calculating an absolute position by referencing the pseudorandom code to the design value; and a position data synthesizing circuit for correcting the absolute position by the peak position, whereby the absolute position can be calculated with a small arithmetic operation amount even if the pseudorandom cod

Abstract: The present invention relates to a photoelectric encoder including a scale having a grating (incremental pattern) of a predetermined pitch formed thereon and a light source (light-emitting element) and a light-receiving unit, which are relatively displaceable with respect to the scale, wherein light-receiving elements of the light-receiving unit output bright and dark signals of “N” phases, and the phases are detected by fitting a sinusoidal wave function having a fixed period to the bright and dark signals of “N” phases, thereby reducing a position detection error resulting from stains on the scale and/or defects of the grating.

Abstract: An absolute position length-measurement type encoder includes a scale having an incremental track, an absolute track, and a reference position track. The incremental track has incremental patterns including first light and dark patterns formed at equal intervals in first periods. The absolute track has absolute patterns representing an absolute position. The reference position track has reference position patterns including second light and dark patterns formed at equal intervals in second periods longer than the first periods. A light source emits a measurement light to the scale. A photodetector receives the measurement light reflected at or transmitted through the scale. A signal processing circuit processes the received light signal of the photodetector to detect an absolute position of the scale.

Abstract: The present invention relates to a photoelectric encoder including a scale having a grating (incremental pattern) of a predetermined pitch formed thereon and a light source (light-emitting element) and a light-receiving unit, which are relatively displaceable with respect to the scale, wherein light-receiving elements of the light-receiving unit output bright and dark signals of “N” phases, and the phases are detectedby fitting a sinusoidal wave function having a fixed period to the bright and dark signals of “N” phases, thereby reducing a position detection error resulting from stains on the scale and/or defects of the grating.

Abstract: A scale has a first incremental track with first incremental patterns including first light and dark patterns formed at equal intervals in first periods, an absolute track with absolute patterns representing absolute positions, and a second incremental track with second incremental patterns including second light and dark patterns formed at equal intervals in second periods longer than the first periods. A light source emits a measurement light to the scale. A photodetector receives the measurement light reflected at or transmitted through the scale. A signal processing circuit processes the received light signal of the photodetector to detect an absolute position of the scale.

Abstract: In an absolute position detection type photoelectric encoder devised so as to detect a pseudorandom pattern disposed on a main scale by means of a plurality of imaging optical systems, assembling of the absolute position detection type photoelectric encoder is facilitated and production cost thereof is reduced by providing: a single light-receiving array element disposed on the imaging surfaces of the imaging optical systems, which incorporates a greater light-receiving array portion in the length measurement direction than the light-receiving range of the respective imaging optical systems; a window signal storing portion for storing a window signal showing a light-receiving range of the respective imaging optical systems; and a window signal comparison portion for obtaining signals corresponding to individual imaging ranges by comparing scanning signals of the light-receiving array element with window signals.

Abstract: The absolute position length measurement type encoder is provided with a scale for forming bright and dark patterns by the ABS pattern based on a pseudorandom code; an edge position detection circuit for obtaining a position, at which an after-differentiated absolute value of a binarized value is locally maximized, for each of the minimum line width zones of the ABS pattern by binarizing a signal from the light-receiving element that receives the bright and dark pattern; a peak position detection circuit for obtaining the peak position from a histogram with respect to the position; a decoding circuit for decoding the pseudorandom code based on the binarized value; an absolute position detection circuit for calculating an absolute position by referencing the pseudorandom code to the design value; and a position data synthesizing circuit for correcting the absolute position by the peak position, whereby the absolute position can be calculated with a small arithmetic operation amount even if the pseudorandom cod

Abstract: An absolute position length measurement type encoder includes: a scale which has an ABS pattern based on a pseudorandom code and forms bright and dark patterns by the ABS pattern; a light-receiving element for receiving the bright and dark patterns; a binarization circuit for dividing a digital signal in accordance with a signal output from the light-receiving element into a mode having high brightness and a mode having lower brightness, carrying out a binarization process by a threshold value where dispersion with regard to the two modes, is maximized, and decoding the pseudorandom code by the unit of minimum line width of the ABS pattern from the binarized values; and a position detection circuit for calculating the absolute position of the scale with respect to the light-receiving element by acquiring the correlation between the decoded pseudorandom code and the design value of the pseudorandom code.

Abstract: A displacement detecting encoder including a scale having a positional code that contains positional information, a detection portion which is disposed so as to make a relative movement with respect to the scale and detect at least a part of the positional code equipped on the scale and a processing portion which processes a part of the positional code detected by the detection portion, thereby outputting the positional information, wherein the detected positional code is evaluated by positional code generating means for generating the positional code to detect the presence or absence of erroneous information. Thereby, an error in detecting a pseudo random code is detected by using a minimum code without addition of a redundant code and also correction can be made, thereby improving the reliability of generating ABS position signals.

Abstract: A scale has a first incremental track with first incremental patterns including first light and dark patterns formed at equal intervals in first periods, an absolute track with absolute patterns representing absolute positions, and a second incremental track with second incremental patterns including second light and dark patterns formed at equal intervals in second periods longer than the first periods. A light source emits a measurement light to the scale. A photodetector receives the measurement light reflected at or transmitted through the scale. A signal processing circuit processes the received light signal of the photodetector to detect an absolute position of the scale.

Abstract: An absolute position length-measurement type encoder includes a scale having an incremental track, an absolute track, and a reference position track. The incremental track has incremental patterns including first light and dark patterns formed at equal intervals in first periods. The absolute track has absolute patterns representing an absolute position. The reference position track has reference position patterns including second light and dark patterns formed at equal intervals in second periods longer than the first periods. A light source emits a measurement light to the scale. A photodetector receives the measurement light reflected at or transmitted through the scale. A signal processing circuit processes the received light signal of the photodetector to detect an absolute position of the scale.

Abstract: A displacement detecting encoder including a scale having a positional code that contains positional information, a detection portion which is disposed so as to make a relative movement with respect to the scale and detect at least a part of the positional code equipped on the scale and a processing portion which processes a part of the positional code detected by the detection portion, thereby outputting the positional information, wherein the detected positional code is evaluated by positional code generating means for generating the positional code to detect the presence or absence of erroneous information. Thereby, an error in detecting a pseudo random code is detected by using a minimum code without addition of a redundant code and also correction can be made, thereby improving the reliability of generating ABS position signals.