A system includes a vessel floating on a body of water. The system also includes at least one conduit extending from the vessel to below the body of water. The system also includes a scanning device disposed within the at least one conduit. The scanning device includes at least one two-dimensional (2D) line scanner and a rotary encoder coupled to the at least one 2D line scanner. The scanning device is configured to generate three-dimensional (3D) image data of a surface of the at least one conduit or at least one component disposed within the at least one conduit.

A method for three-dimensional (3D) image calibration for a spectral domain optical coherence tomography (OCT) system, the OCT system including a scanning arrangement for laterally scanning a sample light beam across a surface of a sample, an optical detection system for detecting light reflected back from the sample to obtain an optical image of the sample, and a reference light beam, the OCT system generating axially resolved optical information from the sample as the sample light beam is scanned laterally across the sample using optical path length differences (OPLD) between the reference light beam and the sample light beam, the method including: providing a calibration sample having a substrate having laterally arranged structural elements providing optical contrast, the structural elements having at least one of known dimensions or known position values on the substrate; scanning, using a first set of scanner parameters for the scanning arrangement, the sample light beam.

Angle-resolved reflectometers and reflectometry methods are provided, which comprise a coherent light source, an optical system arranged to scan a test pattern using a spot of coherent light from the light source to yield realizations of the light distribution in the collected pupil, wherein the spot covers a part of the test pattern and the scanning is carried out optically or mechanically according to a scanning pattern, and a processing unit arranged to generate a composite image of the collected pupil distribution by combining the pupil images. Metrology systems and methods are provided, which reduce diffraction errors by estimating, quantitatively, a functional dependency of measurement parameters on aperture sizes and deriving, from identified diffraction components of the functional dependency which relate to the aperture sizes, correction terms for the measurement parameters with respect to the measurement conditions.

Angle-resolved reflectometers and reflectometry methods are provided, which comprise a coherent light source, an optical system arranged to scan a test pattern using a spot of coherent light from the light source to yield realizations of the light distribution in the collected pupil, wherein the spot covers a part of the test pattern and the scanning is carried out optically or mechanically according to a scanning pattern, and a processing unit arranged to generate a composite image of the collected pupil distribution by combining the pupil images. Metrology systems and methods are provided, which reduce diffraction errors by estimating, quantitatively, a functional dependency of measurement parameters on aperture sizes and deriving, from identified diffraction components of the functional dependency which relate to the aperture sizes, correction terms for the measurement parameters with respect to the measurement conditions.

A system to generate multiple beam lines in an oblique angle multi-beam spot scanning wafer inspection system includes a beam scanning device configured to scan a beam of illumination, an objective lens oriented at an oblique angle relative to the surface of a sample and with an optical axis perpendicular to a first scanning direction on the sample, and one or more optical elements positioned between the objective lens and the beam scanning device. The one or more optical elements split the beam into two or more offset beams such that the two or more offset beams are separated in a least a second direction perpendicular to the first direction. The one or more optical elements further modify the phase characteristics of the two or more offset beams such that the two or more offset beams are simultaneously in focus on the sample during a scan.

A method for determining the refractive index profile of a preform when the RIP is not substantially symmetrical. (i) The preform is scanned, starting with a first projection angle, and raw data are created representing the object through measured data. (ii) Optionally, the object is rotated and step (i) repeated iteratively until all projection angles have been scanned and all measured data have been created. (iii) The measured data are processed to form a sinogram and, if the optional step (ii) has been completed, the method proceeds to step (v). (iv) The object is rotated and steps (i) and (iii) are repeated iteratively until all projection angles have been scanned. (v) A 2D RIP is calculated. (vi) A line section of interest is selected within the 2D RIP. (vii) A fitting procedure is applied to the line section of interest. (viii) Finally, refractive index steps/gradients and dimensions are determined.

The optical interrogation technique can use an optical prism having two opposite sides including a sample side and a refraction side, the sample side having a plurality of interrogation areas; a source assembly generating a collimated field of illumination directed towards the refraction side; a screen disposed in a screen plane intersecting the field of illumination and shielding the refraction side from the field of illumination, the screen having an aperture allowing a portion of the field of illumination to reach and be refracted by the refraction side, be totally internally reflected at one of said interrogation areas of the sample side, thereby generating a signal, the signal refracted back through the aperture, the screen being movable within the screen plane to shift the aperture and expose different portions of the field of illumination to corresponding ones of the interrogation areas.

A system includes a vessel floating on a body of water. The system also includes at least one conduit extending from the vessel to below the body of water. The system also includes a scanning device disposed within the at least one conduit. The scanning device includes at least one two-dimensional (2D) line scanner and a rotary encoder coupled to the at least one 2D line scanner. The scanning device is configured to generate three-dimensional (3D) image data of a surface of the at least one conduit or at least one component disposed within the at least one conduit.

A system includes a vessel floating on a body of water. The system also includes at least one conduit extending from the vessel to below the body of water. The system also includes a scanning device disposed within the at least one conduit. The scanning device includes at least one two-dimensional (2D) line scanner and a rotary encoder coupled to the at least one 2D line scanner. The scanning device is configured to generate three-dimensional (3D) image data of a surface of the at least one conduit or at least one component disposed within the at least one conduit.

The device has an apparatus for rotatably holding and positioning at least one stent-like object and a unit for illuminating at least inner and outer surfaces thereof, including at least a wide field epi illumination device and a diffuse back illumination device for simultaneously illuminating the stent-like object. The illumination unit may further include diffuse side illumination device for inspecting side surfaces of the stent-like object. An apparatus for acquiring images of the stent-like object including at least one microscope objective lens and at least one camera is also provided.