The present invention relates to a measuring device for characterising a shape of a surface of an item, such as a wind turbine blade fibre layup, wherein the measuring device comprises: a frame comprising a holding frame, a first set of two or more probes movably held in the holding frame, each probe having a respective probe end for contacting the surface of the item, and electronic sensing means configured to provide for each probe a respective electrical signal representative of a position of the probe relative to the holding frame. A method for calibrating such a device is provided. Further, a method for characterising a shape of a surface of an item is provided.

Disclosed is a full-hydraulic automatic diaphragm wall cutting-grooving machine, which includes a supporting frame, a cutting device, a cutting driving device and a verticality detection device. The verticality detection device is used to detect the verticality and flatness of the diaphragm wall during the cutting process, the cutting device is used to drive the supporting frame and an equipment arranged on the supporting frame to move and cut, the cutting driving device is used to drive and adjust the cutting device in different directions. The verticality detection device is used to realize the automatic measurement of the verticality of the wall and the bottom surface and the flatness of the wall during the cutting process.

A large-size synthetic quartz glass substrate has a diagonal length of at least 1,000 mm. Provided that an effective range is defined on the substrate surface, and the effective range is partitioned into a plurality of evaluation regions such that the evaluation regions partly overlap each other, a flatness in each evaluation region is up to 3 μm. From the quartz glass substrate having a high flatness and a minimal local gradient within the substrate surface, a large-size photomask is prepared.

Some embodiments of the disclosure provide a flatness detection device. In an embodiment, the flatness detection device includes a back plate, an electromagnet, a cross beam, a probe, and a limiting frame. The limiting frame and the electromagnet are provided side by side on the back plate. The cross beam is located above the limiting frame and the electromagnet. The probe vertically penetrates the cross beam and the limiting frame. A spring is provided between the cross beam and the electromagnet. The spring is movable in a vertical direction by a guide, the movement being at least one of compression and extension.

An indium phosphide substrate, a method of inspecting thereof and a method of producing thereof are provided, by which an epitaxial film grown on the substrate is rendered excellently uniform, thereby allowing improvement in PL characteristics and electrical characteristics of an epitaxial wafer formed using this epitaxial film. The indium phosphide substrate has a first main surface and a second main surface, a surface roughness Ra1 at a center position on the first main surface, and surface roughnesses Ra2, Ra3, Ra4, and Ra5 at four positions arranged equidistantly along an outer edge of the first main surface and located at a distance of 5 mm inwardly from the outer edge. An average value m1 of the surface roughnesses Ra1, Ra2, Ra3, Ra4, and Ra5 is 0.5 nm or less, and a standard deviation σ1 of the surface roughnesses Ra1, Ra2, Ra3, Ra4, and Ra5 is 0.2 nm or less.

A plate flatness measurement device, including a support frame including a center area, the center area including a through-hole in a center of the center area, and a peripheral area surrounding the center area, the peripheral area having a plate with protrusions on a bottom surface of the plate mounted to the peripheral area; and a sensor module in the support frame, the sensor module at least partially protruding above the support frame to contact the protrusions.

A method and a device that performs the method for measuring the flatness of a metal product traveling on a path, the method includes measuring a first longitudinal tension measurement value (T1) with a measuring roller, determining a model of stress over the thickness of the metal product as a function of plastic or elastoplastic deformation of the product, calculating a correction factor for the longitudinal deformation according to the stress model, calculating a corrective value (T1′, T2′) for the first longitudinal tension measurement value (T1) at at least one evaluation point (M1, M2) as a function of the longitudinal deformation correction factor (Z1), and calculating a corrected flatness measurement value (PC) at at least one of the evaluation points.

A measurement device can include a plurality of wheel support modules. Each of the wheel support modules can be configured to attach to a different type of vehicle wheel and to provide for rotation of the vehicle wheel about an axis. An arm can be removably attached to the first wheel support module. A measurement element that measures deformation of the vehicle wheel can be moveably attached to the arm. The different configuration of each of the wheel support modules allows for various types of vehicle wheels to be measured for deformation using the same measurement device.

A measurement apparatus includes a horizontal plate. The horizontal plate includes a first plate end, a second plate end disposed away from the first plate end in a longitudinal direction, a first plate surface extending between the first plate end and the second plate end, and a second plate surface extending between the first plate end and the second plate end. The second plate surface is disposed away from the first plate surface in a normal direction. A first support member extends from the first plate end longitudinally toward the second plate end and protrudes in a direction normally away from the second plate surface. A second support member extends from the first plate end longitudinally toward the second plate end and protrudes in a direction normally away from the second plate surface. A measurement bar contacts the first support member and the second support member.

Methods and apparatus provide for obtaining a gravity free shape, and intrinsic shape, and a thermal strain of a glass sheet and using same to improve glass manufacturing techniques.