System and methods are provided for characterizing an internal surface of a lens using interferometry measurements. Sphere-fitting a distorted radius determines distorted pathlengths. Ray-tracing simulates refraction at all upstream surfaces to determine a cumulative path length. A residual pathlength is scaled by the group-index and rays are propagated based on the phase-index. After aspheric surface fitting, a corrected radius is determined. To estimate a glass type for the lens, a thickness between focal planes of the lens surfaces is determined using RCM measurements. Then, for both surfaces, the surface is positioned into focus, interferometer path length matching is performed, a reference arm is translated to stationary phase point positions for three wavelengths to determine three per-color optical thicknesses, and ray-tracing is performed. A glass type is identified by minimizing an error function based on optical parameters of the lens and parameters determined from known glass types from a database.

The invention relates to a method for contactless recording of a track geometry of a track by means of a rail vehicle which is moved along the track on on-track undercarriages (4), wherein profile data of the track extending in transverse direction are compiled by means of a laser scanner. In this, it is provided that, by means of an evaluation device, profile data are evaluated relative to a reference base pre-defined on the rail vehicle in order to derive from this the course of a track central axis and/or a rail. The invention additionally relates to a rail vehicle which comprise an evaluation device configured for carrying out the method. Thus, no further measuring system is required to determine a track position.

The invention relates to a method for contactless recording of a track geometry of a track by means of a rail vehicle which is moved along the track on on-track undercarriages (4), wherein profile data of the track extending in transverse direction are compiled by means of a laser scanner. In this, it is provided that, by means of an evaluation device, profile data are evaluated relative to a reference base pre-defined on the rail vehicle in order to derive from this the course of a track central axis and/or a rail. The invention additionally relates to a rail vehicle which comprise an evaluation device configured for carrying out the method. Thus, no further measuring system is required to determine a track position.

The present invention relates to a method, and a corresponding device, for testing a radius of curvature and/or for detecting inhomogeneities of a curved X-ray grating for a grating-based X-ray imaging device. The method comprises generating a beam of light diverging from a source point, propagating along a main optical axis and having a line-shaped beam profile. The method comprises reflecting the beam off a concave reflective surface of the grating. A principal axis of the concave reflective surface coincides with the main optical axis and the source point is at a predetermined distance from a point where the main optical axis intersects the concave reflective surface. The method comprises determining whether a projection of the reflected beam in a plane at or near the source point is present outside a central region around the source point, in which an absence of this projection outside the central region indicates that a radius of curvature of the concave reflective surface corresponds to the predetermined distance and/or that the reflective surface is substantially homogeneously curved along a curve formed by the beam impinging on the concave reflective surface.

The present invention relates to a method, and a corresponding device, for testing a radius of curvature and/or for detecting inhomogeneities of a curved X-ray grating for a grating-based X-ray imaging device. The method comprises generating a beam of light diverging from a source point, propagating along a main optical axis and having a line-shaped beam profile. The method comprises reflecting the beam off a concave reflective surface of the grating. A principal axis of the concave reflective surface coincides with the main optical axis and the source point is at a predetermined distance from a point where the main optical axis intersects the concave reflective surface. The method comprises determining whether a projection of the reflected beam in a plane at or near the source point is present outside a central region around the source point, in which an absence of this projection outside the central region indicates that a radius of curvature of the concave reflective surface corresponds to the predetermined distance and/or that the reflective surface is substantially homogeneously curved along a curve formed by the beam impinging on the concave reflective surface.

This invention provides a system and a method for supporting the operation of subsea installations for 3D reconstruction of flexible pipes (1) during a direct vertical connection operation, comprising the steps of painting the flexible pipe (1) with a specific regular pattern, and performing a 3D reconstruction of the points sampled on the flexible pipe (1) to obtain the radius of curvature of the flexible pipe (1), in which the 3D reconstruction comprises the steps of: capturing images of the flexible pipe (1) during the direct vertical connection operation; sending the captured images to a dedicated computer (4); and processing the captured images, generating information on the radius of curvature, wherein the method initially comprises at least one of the following steps: painting the bend restrictor (6) with a specific regular pattern; painting straps (71) for buoys (7) with a specific regular pattern; and painting straps (71) for the arch bend, in the event of second-end direct vertical connection.

A method and test apparatus determines a volume of a droplet of liquid. The test apparatus deposits a drop of liquid to be measured on a surface that provides a known contact angle with the liquid under the deposition conditions used, thereby establishing one of: (i) an advancing, (ii) a receding, and (iii) an intermediate contact angle. The test apparatus images the drop. The test apparatus measures a dimension of height or diameter of the drop. In one embodiment, the test apparatus calculates a volume of the drop of liquid from the relationship of the contact angle to one or more parameters selected from the maximum height, the diameter of the contact patch, the radius of curvature, or the cross sectional area of the drop.

A method and test apparatus determines a volume of a droplet of liquid. The test apparatus deposits a drop of liquid to be measured on a surface that provides a known contact angle with the liquid under the deposition conditions used, thereby establishing one of: (i) an advancing, (ii) a receding, and (iii) an intermediate contact angle. The test apparatus images the drop. The test apparatus measures a dimension of height or diameter of the drop. In one embodiment, the test apparatus calculates a volume of the drop of liquid from the relationship of the contact angle to one or more parameters selected from the maximum height, the diameter of the contact patch, the radius of curvature, or the cross sectional area of the drop.

Bend information computation apparatus includes: an input unit having detected light quantity information representing a relation between a wavelength in a predetermined wavelength band and a light quantity, the detected light quantity information being acquired using a light guide having at least one light absorber for changing a light quantity of light transmitted through the light guide according to a bent state of the light absorber to detect a light quantity after a change; and an arithmetic operator for computing bend information representing a bend direction and a bend magnitude of each light absorber based on the detected light quantity information, an absorption spectrum of each light absorber, a bend coefficient of each light absorber that varies according to a bend direction and a bend magnitude of each light absorber, and a unique characteristic value of each light absorber including a value for a correction relating to the bend coefficient.

System and methods are provided for characterizing an internal surface of a lens using interferometry measurements. Sphere-fitting a distorted radius determines distorted pathlengths. Ray-tracing simulates refraction at all upstream surfaces to determine a cumulative path length. A residual pathlength is scaled by the group-index and rays are propagated based on the phase-index. After aspheric surface fitting, a corrected radius is determined. To estimate a glass type for the lens, a thickness between focal planes of the lens surfaces is determined using RCM measurements. Then, for both surfaces, the surface is positioned into focus, interferometer path length matching is performed, a reference arm is translated to stationary phase point positions for three wavelengths to determine three per-color optical thicknesses, and ray-tracing is performed. A glass type is identified by minimizing an error function based on optical parameters of the lens and parameters determined from known glass types from a database.