An optical encoder includes an origin point detection scale having an origin point detection pattern and an inverse origin point detection pattern that is the inverse of the origin point detection pattern; a light source emitting light at the origin point detection scale; a light source grid that is inserted on the light source side of the origin point detection scale, the light source grid having two first light source grid patterns corresponding to the origin point detection pattern and the inverse origin point detection pattern, respectively; a photoreceiver detecting a signal from light that has passed through the origin point detection scale; and a photoreceiver grid inserted on the photoreceiver side of the origin point detection scale, the photoreceiver grid having two first photoreceiver grid patterns that are a pattern either identical to or the inverse of the first light source grid pattern.

A time grating linear displacement sensor based on an alternating light field, comprising a fixed pole plate and a movable pole plate, wherein the upper part and the lower part of the fixed pole plate are respectively provided with a row of square fixed pole plate light-transmitting surfaces which are uniformly distributed; the upper part and the lower part at the rear of the fixed pole plate are respectively provided with one group of light-emitting devices; the upper part and the lower part of the movable pole plate are respectively provided with two semi-sinusoidal movable pole plate light-transmitting surfaces; and four light-sensitive receiving units are fixed on the movable pole plate, the photoelectric receiving surfaces of the light-sensitive receiving units covering the movable pole plate light-transmitting surfaces. The two groups of light-emitting devices respectively provide an alternating light field. The movable pole plate moves relative to the fixed pole plate.

A time grating linear displacement sensor based on an alternating light field, comprising a fixed pole plate and a movable pole plate, wherein the upper part and the lower part of the fixed pole plate are respectively provided with a row of square fixed pole plate light-transmitting surfaces which are uniformly distributed; the upper part and the lower part at the rear of the fixed pole plate are respectively provided with one group of light-emitting devices; the upper part and the lower part of the movable pole plate are respectively provided with two semi-sinusoidal movable pole plate light-transmitting surfaces; and four light-sensitive receiving units are fixed on the movable pole plate, the photoelectric receiving surfaces of the light-sensitive receiving units covering the movable pole plate light-transmitting surfaces. The two groups of light-emitting devices respectively provide an alternating light field. The movable pole plate moves relative to the fixed pole plate.

An optical element for generating diffraction orders for an encoder apparatus, in which the optical element includes an array of diffraction features arranged such that the spacing between the centers of adjacent diffraction features varies irregularly from one pair of adjacent features to the next.

The present invention provides: a rotary encoder checking an eccentricity state of a scale by sensor units; and related matters. The scale moves, relatively to the sensor units, around a rotational axis line. The pair of sensor units are arranged opposite to each other sandwiching the rotational axis line C0 therebetween. A processing system acquires output signals from each of the sensor units, at a plurality of rotation angles at which the scale has moved relatively to the sensor units. The processing system determines first phase information based on the output signal obtained from the sensor unit, and second phase information based on the output signal obtained from the sensor unit. The processing system determines eccentricity information based on a differential value between any one of the first phase information and the second phase information and an average value of the first phase information and the second phase information.

A system for controlling an elevator comprises a car door operation control system (10) for controlling movement of at least one car door (12), the car door operating control system (10) including an incremental encoder configured to provide a signal indicative of a travel distance of the car door (12) to the car door operating control system (10), and an elevator car control system (50) configured to obtain a primary Car Door Closed Signal from a car door safety switch of an elevator safety control system, said elevator car control system (50) configured to obtain a secondary Car Door Closed Signal (DFCM) independent of the primary Car Door Closed Signal based on the travel distance signal provided by the car door operation control system (10).

A system for controlling an elevator comprises a car door operation control system (10) for controlling movement of at least one car door (12), the car door operating control system (10) including an incremental encoder configured to provide a signal indicative of a travel distance of the car door (12) to the car door operating control system (10), and an elevator car control system (50) configured to obtain a primary Car Door Closed Signal from a car door safety switch of an elevator safety control system, said elevator car control system (50) configured to obtain a secondary Car Door Closed Signal (DFCM) independent of the primary Car Door Closed Signal based on the travel distance signal provided by the car door operation control system (10).

In implementations of a linear encoder force transducer, an encoder component generates light that enters a light input window of an encoder strip, and reflective surfaces disperse the light internally within the encoder strip. The encoder strip has etched lines formed cross-width of the encoder strip for emitted light that exits the encoder strip. The encoder component has gradated slots through which the emitted light from the encoder strip is detected by an array of photo transistors, each of the gradated slots corresponding to one of the photo transistors in the array of photo transistors. An encoder module can determine a linear displacement, such as representative of a force applied to a pen tip of a computer input pen, based on one or more of the photo transistors detecting the emitted light as the etched lines of the encoder strip move relative to the gradated slots of the encoder component.

A position-measuring system includes a plurality of scanning units for the optical scanning of at least one measuring standard, the scanning units being coupled optically to a plurality of light sources and a plurality of detectors. Disposed between the scanning units and the detectors are a plurality of demultiplexers, via which in each case at least two scanning units are coupled to one detector.

A position-measuring system includes a plurality of scanning units for the optical scanning of at least one measuring standard, the scanning units being coupled optically to a plurality of light sources and a plurality of detectors. Disposed between the scanning units and the detectors are a plurality of demultiplexers, via which in each case at least two scanning units are coupled to one detector.