Abstract: In a spherical shape measurement method for measuring a surface shape, a sphere to be measured is made freely rotatable. The partial spherical shape of each measurement area, which is established so as to have an area overlapping with another measurement area adjacent to each other, is measured at each rotation position, and the surface shape is measured by joining the partial spherical shapes of the measurement areas by a stitching operation based on the shape of the overlapping area. In the state of detaching the sphere from the sphere hold mechanism to which the sphere is freely attachable and detachable, the sphere support table holds the sphere. The sphere is re-held at a different position, so that the shape of the entire sphere can be measured with high accuracy.

Abstract: A measuring probe includes two supporting members, each having a rotationally symmetric shape and allowing for an attitude change of a stylus, in an axial direction of a probe housing. Four detection elements are disposed at fourfold symmetric positions in one of the two supporting members that includes four deformable arm parts. A signal processing circuit includes a first processing part that processes outputs of the detection elements to output three displacement signals representing displacement components of a contact part in mutually perpendicular three directions, respectively. The measuring probe capable of reducing measurement directional dependency of sensitivity with a simple configuration while maintaining high sensitivity is thus provided.

Abstract: A measuring probe includes: a stylus having a contact part to be brought into contact with an object to be measured; a probe housing capable of supporting the stylus on an axial center; and a detection element capable of detecting a movement of the contact part. The measuring probe further includes: two supporting members disposed in an axial direction of the probe housing, the supporting member allowing for an attitude change of the stylus; and a coupling shaft for coupling the two supporting members together. The detection element is disposed in one of the two supporting members that is farthest away from a rotational center position of rotation generated in the stylus when a measuring force is applied to the contact part from a direction perpendicular to the axial direction, to detect a strain amount of the one of the two supporting members.

Abstract: A measurement target and a reference gauge are placed in parallel in an inside of a temperature-controlled chamber. After an interior temperature of the temperature-controlled chamber is set at a first temperature, a relative measurement of a length from a first surface to a second surface of the measurement target is performed with reference to a length from a first reference surface to a second reference surface of the reference gauge. Then, the interior temperature of the temperature-controlled chamber is set at a second temperature and a relative measurement of the length from the first surface to the second surface is similarly performed with reference to the length from the first reference surface to the second reference surface. A CTE of the measurement target is calculated based on the length of the measurement target at the first temperature and the length of the measurement target at the second temperature.

Abstract: A measuring probe includes two supporting members, each having a rotationally symmetric shape and allowing for an attitude change of a stylus, in an axial direction of a probe housing. Four detection elements are disposed at fourfold symmetric positions in one of the two supporting members that includes four deformable arm parts. A signal processing circuit includes a first processing part that processes outputs of the detection elements to output three displacement signals representing displacement components of a contact part in mutually perpendicular three directions, respectively. The measuring probe capable of reducing measurement directional dependency of sensitivity with a simple configuration while maintaining high sensitivity is thus provided.

Abstract: A measuring probe includes: a stylus having a contact part to be brought into contact with an object to be measured; a probe housing capable of supporting the stylus on an axial center; and a detection element capable of detecting a movement of the contact part. The measuring probe further includes: two supporting members disposed in an axial direction of the probe housing, the supporting member allowing for an attitude change of the stylus; and a coupling shaft for coupling the two supporting members together. The detection element is disposed in one of the two supporting members that is farthest away from a rotational center position of rotation generated in the stylus when a measuring force is applied to the contact part from a direction perpendicular to the axial direction, to detect a strain amount of the one of the two supporting members.

Abstract: A measurement target and a reference gauge are placed in parallel in an inside of a temperature-controlled chamber. After an interior temperature of the temperature-controlled chamber is set at a first temperature, a relative measurement of a length from a first surface to a second surface of the measurement target is performed with reference to a length from a first reference surface to a second reference surface of the reference gauge. Then, the interior temperature of the temperature-controlled chamber is set at a second temperature and a relative measurement of the length from the first surface to the second surface is similarly performed with reference to the length from the first reference surface to the second reference surface. A CTE of the measurement target is calculated based on the length of the measurement target at the first temperature and the length of the measurement target at the second temperature.

Abstract: A spherical-form measuring apparatus includes a turntable 5, a holding unit 10 for holding the sphere 20, and a probe 6 for measuring a contour of a sphere part 22 of the sphere 20. The holding unit 10 includes a base part 12, a vertical holding part 14 and an inclined holding part 16 which are placed at separate positions on the base part 12. The vertical holding part 14 holds the stem part 24 of the sphere 20 with it set in a direction perpendicular to the turntable 5. The inclined holding part 16 holds the stem part 24 with it set in a direction at an angle. The vertical and inclined holding part 14, 16 are disposed such that their axial lines meet at an intersection point P and such that the distance from the point P to the vertical holding part 14 agrees with the distance from the point P to the inclined holding part 16.

Abstract: In a spherical shape measurement method for measuring a surface shape, a sphere to be measured is made freely rotatable. The partial spherical shape of each measurement area, which is established so as to have an area overlapping with another measurement area adjacent to each other, is measured at each rotation position, and the surface shape is measured by joining the partial spherical shapes of the measurement areas by a stitching operation based on the shape of the overlapping area. In the state of detaching the sphere from the sphere hold mechanism to which the sphere is freely attachable and detachable, the sphere support table holds the sphere. The sphere is re-held at a different position, so that the shape of the entire sphere can be measured with high accuracy.

Abstract: A grazing incidence interferometer includes: a graduated instrument showing an index at an overlapping area where adjacent ones of measurement areas overlap with each other; and a measuring unit including: an image acquiring unit that acquires interference fringe images at image-capturing positions for the measurement areas, individually, the interference fringe images each showing each of the measurement areas and the index; and a profile computing unit that combines measurement results based on the interference fringe images of the adjacent ones of the measurement areas in a manner that images of the index included in common in the interference fringe images of the adjacent ones of the measurement areas are superimposed on each other.

Abstract: A grazing incidence interferometer includes a light source, a light beam divider configured to divide original light coming from the light source, an illuminator configured to apply measurement light to a measurement subject, a light beam combining module configured to combine the measurement light reflected from the measurement subject with reference light, and a photodetector configure to detect a combined light beam. The grazing incidence interferometer includes an interferometer main body, a stage configured to hold the measurement subject, a moving mechanism capable of moving the interferometer main body along the measurement subject, and an auxiliary reflector disposed on an extension of an axis of movement of the interferometer main body, an auxiliary light beam separator configured to separate auxiliary light from the original light and to apply the auxiliary light to the auxiliary reflector, and an auxiliary photodetector configured to detect the auxiliary light reflected by the auxiliary reflector.

Abstract: An abscissa calibration jig of a laser interference measuring apparatus, includes: an image projection unit configured to project an image with a marker; a first support mechanism configured to rotatably support the image projection unit around a first rotation axis passing a predetermined rotation center; and a second support mechanism configured to rotatably support the first support mechanism around a second rotation axis crossing the first rotation axis at the rotation center.

Abstract: A spherical-form measuring apparatus includes a turntable 5, a holding unit 10 for holding the sphere 20, and a probe 6 for measuring a contour of a sphere part 22 of the sphere 20. The holding unit 10 includes a base part 12, a vertical holding part 14 and an inclined holding part 16 which are placed at separate positions on the base part 12. The vertical holding part 14 holds the stem part 24 of the sphere 20 with it set in a direction perpendicular to the turntable 5. The inclined holding part 16 holds the stem part 24 with it set in a direction at an angle. The vertical and inclined holding part 14, 16 are disposed such that their axial lines meet at an intersection point P and such that the distance from the point P to the vertical holding part 14 agrees with the distance from the point P to the inclined holding part 16.

Abstract: A grazing incidence interferometer includes: a beam splitting section configured to split a beam from a beam source section into a measuring beam emergent to a measurement surface and a reference beam serving as a measurement reference, and configured to cause the measuring beam to emerge obliquely to the measurement surface; a beam combining part configured to combine the reference beam and the measuring beam reflected at the measurement surface, to obtain a combined beam; a detecting section configured to detect a profile of the measurement surface based on an interference fringe formed by the combined beam; and an image inverting part configured to invert an orientation of a wave front of the measuring beam or the reference beam, the image inverting part being provided in an optical path of the measuring beam or the reference beam leading from the beam splitting section to the beam combining section.

Abstract: A Fizeau interferometer includes: a reference spherical surface; and a measuring apparatus including an intensity obtaining section and a form calculating section, wherein: a focal point of the reference spherical surface is aligned with a center of curvature of the spherical surface in order to set the center of curvature as a center position, and two positions equidistant from the center position are set as a start position and an end position, the intensity obtaining section obtains the intensity maps of the interferograms at n positions at equal intervals; and the form calculating section measures the form of the spherical surface using a phase analysis method in which a coefficient of the intensity maps of the interferograms at an i-th position and a coefficient of the intensity maps of the interferograms at an (n?i+1)th position have a same value.

Abstract: An abscissa calibration jig of a laser interference measuring apparatus, includes: an image projection unit configured to project an image with a marker; a first support mechanism configured to rotatably support the image projection unit around a first rotation axis passing a predetermined rotation center; and a second support mechanism configured to rotatably support the first support mechanism around a second rotation axis crossing the first rotation axis at the rotation center.

Abstract: A grazing incidence interferometer includes a light source, a light beam divider configured to divide original light coming from the light source, an illuminator configured to apply measurement light to a measurement subject, a light beam combining module configured to combine the measurement light reflected from the measurement subject with reference light, and a photodetector configure to detect a combined light beam. The grazing incidence interferometer includes an interferometer main body, a stage configured to hold the measurement subject, a moving mechanism capable of moving the interferometer main body along the measurement subject, and an auxiliary reflector disposed on an extension of an axis of movement of the interferometer main body, an auxiliary light beam separator configured to separate auxiliary light from the original light and to apply the auxiliary light to the auxiliary reflector, and an auxiliary photodetector configured to detect the auxiliary light reflected by the auxiliary reflector.

Abstract: A Fizeau interferometer includes: a reference spherical surface; and a measuring apparatus including an intensity obtaining section and a form calculating section, wherein: a focal point of the reference spherical surface is aligned with a center of curvature of the spherical surface in order to set the center of curvature as a center position, and two positions equidistant from the center position are set as a start position and an end position, the intensity obtaining section obtains the intensity maps of the interferograms at n positions at equal intervals; and the form calculating section measures the form of the spherical surface using a phase analysis method in which a coefficient of the intensity maps of the interferograms at an i-th position and a coefficient of the intensity maps of the interferograms at an (n?i+1)th position have a same value.

Abstract: A grazing incidence interferometer includes: a beam splitting section configured to split a beam from a beam source section into a measuring beam emergent to a measurement surface and a reference beam serving as a measurement reference, and configured to cause the measuring beam to emerge obliquely to the measurement surface; a beam combining part configured to combine the reference beam and the measuring beam reflected at the measurement surface, to obtain a combined beam; a detecting section configured to detect a profile of the measurement surface based on an interference fringe formed by the combined beam; and an image inverting part configured to invert an orientation of a wave front of the measuring beam or the reference beam, the image inverting part being provided in an optical path of the measuring beam or the reference beam leading from the beam splitting section to the beam combining section.

Abstract: A precision surface plate has a hollow casing with a reference plane used as a surface on which either or both of a workpiece and mechanical equipment are placed, a honeycomb structure, which is a collection of substantially identically-shaped enclosed cells disposed inside the casing, and a heat transfer device provided in the honeycomb structure to allow cells of the honeycomb structure to communicate with each other and transfer heat. The precision surface plate further includes casing ventilation openings provided in a wall of the casing to allow cells of the honeycomb structure inside the casing to communicate with the outside of the casing, and a shutter for opening and closing the casing ventilation openings. The heat is transferred effectively between the cells of the honeycomb structure through the heat transfer device.