A digital displacement sensor and a displacement measuring method thereof, pertaining to the technical field of displacement sensors. The digital displacement sensor includes a housing and a circuit board, and the circuit board is arranged inside the housing. The housing is provided with a window and an opening. The circuit board is provided with a signal acquisition module, an analog front end circuit, a digital compensation circuit, and a signal output interface. The digital displacement sensor allows to alternatively fix the sensor or measured object according to the structure. The measurement can be performed as long as a relative movement between the sensor and the measured object occurs. Factors such as material of the measured object etc. are not limited, so materials such as steel belts, aluminum plates, plastics etc. can be flexibly used. Merely surfaces of the measured object need to be coated with corresponding stripes.

A measurement device has: a slider which holds a substrate and is movable parallel to the XY plane; a drive system that drives the slider; a position measurement system which emits beams from a head section to a measurement surface in which grating section are provided on the slider, which receives respective return beams of the beams from the measurement surface, and which is capable of measuring position information in at least directions of three degrees of freedom including the absolute position coordinates of the slider; a mark detection system that detects a mark on the substrate; and a controller which detects the marks on the substrate using the mark detection system while controlling the drive of the slider, and which obtains the absolute position coordinates of each mark based on the detection result of each mark and measurement information by the position measurement system at the time of detection.

A pattern for calibration of a detector, including of a series of contrasting light and dark segments; the segments being arranged such that the absolute position of any point on the pattern is determinable from a window portion of the pattern including the point; the window portion having a predetermined minimum number of segments, the predetermined minimum number of segments being less than the total number of segments in the series.

A liquid crystal exposure apparatus that exposes a substrate with an illumination light via a projection optical system is equipped with: a substrate holder that holds the substrate; a substrate encoder system that includes head units and scales, and acquires the position information of the substrate holder on the basis of the output of the head units; and a drive section that relatively moves one of the head units and the scales on the substrate holder with respect to the other.

A three-dimensional coordinate measurement apparatus capable of reducing shaking of a Y carriage and improving measurement accuracy. The Y carriage is supported by two strut members which are across a surface plate and movable in a Y-axis direction. The two strut members include a first strut member having a driving mechanism and a second strut member which moves following the first strut member. A guide portion parallel to the Y-axis direction is formed in the surface plate on a first strut member side. Side surface support members support the first strut member on the surface plate by holding both opposed side surfaces of the guide portion. The driving mechanism includes a roller having an axis perpendicular to a surface plate surface, and the roller is brought into contact with one side surface of the guide portion and rolled to move the Y carriage relatively to the surface plate.

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 drug delivery device comprising: a housing; a cylindrical member rotatably supported within the housing; and a plurality of sensors; wherein: the outer surface of the cylindrical member is provided with a single track, the track forming an encoder and having a plurality of first track segments and a plurality of second track segments arranged along the length of the track which are respectively capable of inducing first and second responses in the sensors; and in each rotational position of the cylindrical member relative to the housing at least one different first track segment is capable of inducing a first response in at least one said sensor, thereby enabling the rotational position of the cylindrical member relative to the housing to be determined.

Example implementations relate to determining a correction factor that converts a measured sensor distance to a calibrated sensor distance. The measured sensor distance may be based on an amount of substrate advancement through a web printing press between detecting a mark on the substrate at a first sensor and detecting the mark at a second sensor. The calibrated sensor distance may be the separation between the first sensor and the second sensor.

Provided is a photoelectric encoder that can achieve higher accuracy while maintaining reliability by reducing stray light. An encoder 1 is a photoelectric encoder including a light source device 2 that emits parallel light, a scale 3 having calibrations C provided along a measurement direction, and a light receiving unit 4 that receives light being emitted from the light source device 2, and transmitted through the scale 3. The encoder 1 includes an antireflection member 30 that prevents stray light generated by being reflected on the scale 3, from entering the light receiving unit 4. Because the encoder 1 includes the antireflection member 30, the encoder 1 can achieve higher accuracy while maintaining reliability by reducing stray light entering the light receiving unit 4.

A three-dimensional coordinate measurement apparatus capable of reducing shaking of a Y carriage and improving measurement accuracy. The Y carriage is supported by two strut members which are across a surface plate and movable in a Y-axis direction. The two strut members include a first strut member having a driving mechanism and a second strut member which moves following the first strut member. A guide portion parallel to the Y-axis direction is formed in the surface plate on a first strut member side. Side surface support members support the first strut member on the surface plate by holding both opposed side surfaces of the guide portion. The driving mechanism includes a roller having an axis perpendicular to a surface plate surface, and the roller is brought into contact with one side surface of the guide portion and rolled to move the Y carriage relatively to the surface plate.