A grating displacement measuring device based on conical diffraction, including a laser diode configured to emit a measuring beam, a collimating lens, a polarizing beam splitter, a first reflecting mirror, a second reflecting mirror, a third reflecting mirror, a fourth reflecting mirror and a phase shift measuring unit. A grating displacement measuring method based on conical diffraction is also provided.

An optical position-measuring device for sensing a relative position of two objects, each object being connected to a grating. The optical position-measuring device is configured such that, at one of the gratings, an illumination beam emitted from a light source is split into two sub-beams which, in respective scanning beam paths following the splitting, experience different polarization-optical effects and recombine at one of the gratings. After the differently polarized sub-beams are recombined, a plurality of phase-shifted, displacement-dependent scanning signals are generatable from a resulting signal beam in a detection unit. No separate polarization-optical components are disposed in the scanning beam paths of the sub-beams between splitting and recombination. At least one of the gratings is configured as a polarization grating configured to produce the different polarization-optical effects and such that diffraction orders with different polarization states are produced at each point of incidence on the polarization grating.

An optical position-measuring device for sensing a relative position of two objects, each object being connected to a grating. The optical position-measuring device is configured such that, at one of the gratings, an illumination beam emitted from a light source is split into two sub-beams which, in respective scanning beam paths following the splitting, experience different polarization-optical effects and recombine at one of the gratings. After the differently polarized sub-beams are recombined, a plurality of phase-shifted, displacement-dependent scanning signals are generatable from a resulting signal beam in a detection unit. No separate polarization-optical components are disposed in the scanning beam paths of the sub-beams between splitting and recombination. At least one of the gratings is configured as a polarization grating configured to produce the different polarization-optical effects and such that diffraction orders with different polarization states are produced at each point of incidence on the polarization grating.

A movable body apparatus that moves a substrate equipped with: a substrate holder which can move in the X-axis and the Y-axis directions; a Y coarse movement stage can move in the Y-axis direction, a first measurement system acquiring position information on the substrate holder with heads provided at the substrate holder and a scale provided at the Y coarse movement stage; a second measurement system acquiring position information on the Y coarse movement stage with heads at the Y coarse movement stage and a scale; and a control system controlling the position of the substrate holder based on position information acquired by the first and the second measurement systems, and the first measurement system irradiates a measurement beam on the scale while moving the heads in the X-axis direction, and the second measurement system irradiates a measurement beam on the scale while moving the heads in the Y-axis direction.

In order to provide an optical encoder with high resolution, the optical encoder includes: a rotary scale provided with a grating pattern having a first radial pattern and a plurality of concentric circular patterns disposed at predetermined intervals; and a light receiving element which detects a first interference fringe formed by the first pattern having a first period in the circumferential direction, a second interference fringe which is diffracted in a direction of the first interference fringe by a grating pattern having a second period in the circumferential direction disposed at a different radial position so that the second interference fringe has a period closer to the first period than the second period.

An optical encoder includes a first grating pattern having a first pitch, a second grating pattern having a second pitch, a third grating pattern having a third pitch different from the second pitch, and a light receiving element configured to receive light from the third grating pattern in an order from a side of a light source, wherein first moire fringes including a shadow of the third grating pattern are formed on an exit plane of the third grating pattern due to a difference between the second pitch and the third pitch, and wherein the light receiving element receives light that forms second moire fringes in which the shadow of the third grating pattern is smoothed more than in the first moire fringes by placing the third grating pattern and the light receiving element away from each other.

A liquid crystal exposure apparatus that irradiates a substrate held by a substrate holder which moves along an XY plane with an illumination light via an optical system while the substrate holder moves in the X-axis direction, has; a scale measured based on movement of the substrate holder in the X-axis direction, heads that measure the scale while relatively moving in the X-axis direction with respect to the scale, a plurality of scales arranged at mutually different positions in the X-axis direction measured based on movement of the substrate holder in the Y-axis direction, and a plurality of heads provided for each scale that measures the scales while relatively moving in the Y-axis direction with respect to the scales based on movement of the substrate in the Y-axis direction.

A liquid crystal exposure apparatus that irradiates a substrate held by a substrate holder which moves along an XY plane with an illumination light via an optical system while the substrate holder moves in the X-axis direction, has; a scale measured based on movement of the substrate holder in the X-axis direction, heads that measure the scale while relatively moving in the X-axis direction with respect to the scale, a plurality of scales arranged at mutually different positions in the X-axis direction measured based on movement of the substrate holder in the Y-axis direction, and a plurality of heads provided for each scale that measures the scales while relatively moving in the Y-axis direction with respect to the scales based on movement of the substrate in the Y-axis direction.

A displacement measuring apparatus, a displacement measuring method and a photolithography device are disclosed. The displacement measuring apparatus includes a light source module (300), a diffractive member (200), a reader head assembly (100), an optical detection module (410, 411, 412, 413) and a signal analysis module (500). The reader head assembly (100) is configured to receive two input light beams (610, 611) from the light source module (300) and guide them so that they come into contact in parallel with the diffractive member (200) and are both diffracted. The diffracted input light beams are guided and combined to form at least one output light beam (612, 613, 614) each containing diffracted light signals respectively of the two input light beams (610, 611), which exit in the same direction from the same light spot location of the diffractive member (200). Displacement information of the diffractive member (200) can be derived from phase change information contained in an interference signal produced by each output light beam (612, 613, 614). The displacement measuring apparatus and method can be used to achieve independent displacement measurements in different direction, with adaptivity to a wide angle and reduced nonlinearity errors. The photolithography device includes the displacement measuring apparatus.

A displacement measuring apparatus, a displacement measuring method and a photolithography device are disclosed. The displacement measuring apparatus includes a light source module (300), a diffractive member (200), a reader head assembly (100), an optical detection module (410, 411, 412, 413) and a signal analysis module (500). The reader head assembly (100) is configured to receive two input light beams (610, 611) from the light source module (300) and guide them so that they come into contact in parallel with the diffractive member (200) and are both diffracted. The diffracted input light beams are guided and combined to form at least one output light beam (612, 613, 614) each containing diffracted light signals respectively of the two input light beams (610, 611), which exit in the same direction from the same light spot location of the diffractive member (200). Displacement information of the diffractive member (200) can be derived from phase change information contained in an interference signal produced by each output light beam (612, 613, 614). The displacement measuring apparatus and method can be used to achieve independent displacement measurements in different direction, with adaptivity to a wide angle and reduced nonlinearity errors. The photolithography device includes the displacement measuring apparatus.