Abstract: An absolute encoder includes a scale having a sequence of marks, a detector configured to detect a signal corresponding to a plurality of marks of the scale, and a processor configured to obtain an absolute position corresponding to the signal. The processor is configured to select code sequences, from a group of code sequences corresponding to absolute positions, as a candidate group for a code sequence corresponding to the signal, and to select the code sequence corresponding to the signal from the candidate group.

Abstract: An absolute encoder includes: a scale on which plural marks are arrayed; plural detecting devices each configured to detect a mark group of the plural marks and output a signal corresponding to the mark group; and a processor configured to obtain a coordinate of the scale based on outputs of the detecting devices. The plural marks are arrayed such that a signal obtained by adding plural signals respectively output from the detecting devices includes a periodic signal corresponding to plural periods. The processor obtains first position data based on a magnitude of at least one signal of the plural signals, obtains second position data having a resolution higher than that of the first position data based on a phase of the periodic signal, and generates data representing the coordinate based on the first and second position data.

Abstract: A measurement apparatus includes: a projection device configured to project, upon an object, light having a pattern and light not having a pattern; an imaging device configured to image the object upon which the light having a pattern has been projected and obtain a pattern image, and image the object upon which the light not having a pattern has been projected and obtain an intensity image; and a processor configured to perform processing of recognizing a region of the object, by performing processing of correcting distortion in the pattern image, based on first calibration data, and performing processing of correcting distortion in the intensity image, based on second calibration data different from the first calibration data.

Abstract: A measurement apparatus includes: a detector which detects modulated light from the target object and outputs a periodic pattern signal; and a calculation unit which determines positions of two extreme values from the signal output from the detector, calculates a first total sum by multiplying the signal by first reference data in a region between the positions of the two extreme values, and adding the multiplication results, calculates a second total sum by multiplying the signal by second reference data with a phase difference of 90° with respect to the first reference data in the region, and adding the multiplication results, calculates a phase of the signal based on the first and second total sums, and calculates the position of the target object based on the calculated phase.

Abstract: A two-dimensional absolute encoder includes a scale having marks arranged thereon along first and second directions different from each other, a detector configured to perform first detection that detects rows of a first number of marks arranged in the first direction and second detection that detects rows of a second number of marks arranged in the second direction, and a processor configured to determine absolute positions of the scale in the first and second directions based on outputs from the detector. Each of the marks has one of different characteristic values each corresponding to a combination of a quantized first code for indicating a position in the first direction and a quantized second code for indicating a position in the second direction, the number of the different characteristic values being smaller than the number of the combinations.

Abstract: An absolute encoder includes: a scale on which plural marks are arrayed; plural detecting devices each configured to detect a mark group of the plural marks and output a signal corresponding to the mark group; and a processor configured to obtain a coordinate of the scale based on outputs of the detecting devices. The plural marks are arrayed such that a signal obtained by adding plural signals respectively output from the detecting devices includes a periodic signal corresponding to plural periods. The processor obtains first position data based on a magnitude of at least one signal of the plural signals, obtains second position data having a resolution higher than that of the first position data based on a phase of the periodic signal, and generates data representing the coordinate based on the first and second position data.

Abstract: Provided is an absolute encoder that includes a scale in which a plurality of marks including a plurality of types of marks is arrayed with a gap and a period; a detector including a plurality of elements and configured to detect marks of the plurality of marks with the plurality of elements; and a processor configured to: generate a data sequence by quantizing periodic signals with a plurality of periods obtained by the detector with respect to each of the plurality of periods, and generate a first position data based on the data sequence; generate a second position data corresponding to a phase of a signal obtained by decreasing values of the periodic signals with respect to both end portions thereof; and generate data representing the absolute position based on the first position data and the second position data.

Abstract: An absolute encoder includes a scale having a sequence of marks, a detector configured to detect a signal corresponding to a plurality of marks of the scale, and a processor configured to obtain an absolute position corresponding to the signal. The processor is configured to select code sequences, from a group of code sequences corresponding to absolute positions, as a candidate group for a code sequence corresponding to the signal, and to select the code sequence corresponding to the signal from the candidate group.

Abstract: A measurement apparatus includes: a detector which detects modulated light from the target object and outputs a periodic pattern signal; and a calculation unit which determines positions of two extreme values from the signal output from the detector, calculates a first total sum by multiplying the signal by first reference data in a region between the positions of the two extreme values, and adding the multiplication results, calculates a second total sum by multiplying the signal by second reference data with a phase difference of 90° with respect to the first reference data in the region, and adding the multiplication results, calculates a phase of the signal based on the first and second total sums, and calculates the position of the target object based on the calculated phase.

Abstract: A two-dimensional absolute encoder includes a scale having marks arranged thereon along first and second directions different from each other, a detector configured to perform first detection that detects rows of a first number of marks arranged in the first direction and second detection that detects rows of a second number of marks arranged in the second direction, and a processor configured to determine absolute positions of the scale in the first and second directions based on outputs from the detector. Each of the marks has one of different characteristic values each corresponding to a combination of a quantized first code for indicating a position in the first direction and a quantized second code for indicating a position in the second direction, the number of the different characteristic values being smaller than the number of the combinations.

Abstract: A scanning exposure apparatus (300) includes a first stage (325), a second stage (345), a projection optical system (330), a first measurement unit (20) arranged on the second stage (345), and a controller (350). A measurement mask (10) is arranged on the first stage (325). The first measurement unit (20) includes a light-shielding member having an opening, and measures the intensity of light having passed through the opening in a light intensity distribution formed on the light-shielding member when at least one of the first stage (325) and the second stage (345) is scanned and a measurement pattern of the measurement mask (10) is obliquely illuminated. The controller (350) calculates the defocus amount, while at least one of the first stage (325) and the second stage (345) is scanned, based on a temporal change in the light intensity measured by the first measurement unit (20).

Abstract: A measurement apparatus for measuring wavefront aberration of an optical system to be measured comprises a pinhole mask having a pinhole, an illumination optical system configured to illuminate the pinhole mask, a test pattern disposed between the pinhole mask and the optical system to be measured, a detector configured to detect an image formed on an image plane of the optical system to be measured by light having passed through the pinhole, the test pattern, and the optical system to be measured, and an optical member which is disposed or inserted in the illumination optical system, and configured to control an illuminance distribution in a pupil region of the optical system to be measured so that a peripheral portion in the pupil region includes a portion having an illuminance higher than an illuminance in a central portion in the pupil region.

Abstract: A scanning exposure apparatus (300) includes a first stage (325), a second stage (345), a projection optical system (330), a first measurement unit (20) arranged on the second stage (345), and a controller (350). A measurement mask (10) is arranged on the first stage (325). The first measurement unit (20) includes a light-shielding member having an opening, and measures the intensity of light having passed through the opening in a light intensity distribution formed on the light-shielding member when at least one of the first stage (325) and the second stage (345) is scanned and a measurement pattern of the measurement mask (10) is obliquely illuminated. The controller (350) calculates the defocus amount, while at least one of the first stage (325) and the second stage (345) is scanned, based on a temporal change in the light intensity measured by the first measurement unit (20).