An optical axis adjusting method includes a position detecting step of emitting a laser beam from a laser oscillator, applying the laser beam to a processing point, and detecting the position of the laser beam by using a position detecting unit set at the processing point, a storing step of storing the position of the laser beam as detected in the position detecting step as a reference position, and an adjusting step of operating an adjusting mechanism of each optical component holder in the case that the position of the laser beam is deviated from the reference position after performing maintenance of each optical component, thereby adjusting the position of the laser beam so that the position of the laser beam is shifted back to the reference position.

An optical axis adjusting method includes a position detecting step of emitting a laser beam from a laser oscillator, applying the laser beam to a processing point, and detecting the position of the laser beam by using a position detecting unit set at the processing point, a storing step of storing the position of the laser beam as detected in the position detecting step as a reference position, and an adjusting step of operating an adjusting mechanism of each optical component holder in the case that the position of the laser beam is deviated from the reference position after performing maintenance of each optical component, thereby adjusting the position of the laser beam so that the position of the laser beam is shifted back to the reference position.

The invention relates to installations for fibre optic monitoring of articles, and apparatus and methods for forming such installations, including a modular system and components for forming a fibre optic monitoring installation. Applications of the invention include the monitoring of vessels, chambers, and fluid conduits in industrial processing plants, and the invention has particular application to monitoring large vessels, for example temperature monitoring of vessels used in catalytic reforming processes. Convenient installation on or removal from the article being monitored is achieved by providing a support structure for the fibre optic length, which presents the fibre optic length in a preconfigured orientation suitable for monitoring the article. In a particular embodiment of the invention, the fibre optic length is disposed on a panel in a plurality of dense spiral patterns.

A method and apparatus for automatic determination of a fiber type of at least one optical fiber span used in a link of an optical network, the method comprising the steps of measuring a length of said optical fiber span; measuring a chromatic dispersion of said optical fiber span; determining a fiber dispersion profile of said optical fiber span on the basis of the measured length and the measured fiber chromatic dispersion; and determining a fiber category and/or a specific fiber type of said optical fiber span depending on the determined fiber dispersion profile.

Methods for estimating the Effective Modal Bandwidth (EMB) of laser optimized Multimode Fiber (MMF) at a specified wavelength, λ.sub.S, based on the measured EMB at a first reference measurement wavelength, λ.sub.M. In these methods the Differential Mode Delay (DMD) of a MMF is measured and the Effective Modal Bandwidth (EMB) is computed at a first measurement wavelength. By extracting signal features such as centroids, peak power, pulse widths, and skews, as described in this disclosure, the EMB can be estimated at a second specified wavelength with different degrees of accuracy. The first method estimates the EMB at the second specified wavelength based on measurements at the reference wavelength. The second method predicts if the EMB at the second specified wavelength is equal or greater than a specified bandwidth limit.

An optical probe includes an optical housing, a transmitting lens and a receiving lens. The optical housing extends from a proximate end to an opposing distal end. The transmitting lens is disposed at the distal end and is configured to output a first transmitted signal beams having a first transmission axis and a second transmitted beam having a second transmission axis that is different from the first transmission axis. The receiving lens is disposed at the distal end and configured to receive the first and second reflected signal beams corresponding respectively to the first and second transmitted signal beams. The optical housing has formed therein a transmitting optical channel configured to communicate an input optical signal from the proximate end to the transmitting lens. A receiving optical channel separated from the transmitting optical channel communicates the first and second reflected signal beams to the proximate end.

A method includes the steps of arranging mark points for image recognition on a plane of a test piece to be measured; recognizing and recording positions of two-dimensional Cartesian coordinates of each mark point of the test piece to be measured before and after each stretching; and determining a deformation gradient of each mark point and deformation measurement parameters of each mark point through a numerical method, where the deformation measurement parameters include a deformation gradient matrix, an elongation tensor matrix, a finite strain tensor matrix, an orthogonal tensor matrix, an angular tensor matrix, a rotation angle, and a curvature. According to the method, objective measurement of super-large deformation of the plane relating to rotation deformation is achieved.

A system includes a stage, a detector and a measuring device. The stage is configured to hold a substrate. The substrate includes a plurality of tapered structures, and each of the plurality of tapered structures includes a tapered wall between first and second openings at opposite ends of the plurality of tapered structures. The detector is tilted at a first angle and configured to measure light reflected from the tapered wall at about 90 degrees to the tapered wall. The first angle depends at least in part a second angle between the tapered wall and a longitudinal axis running through the tapered structure. The measuring device is configured to determine a characteristic of the tapered wall and whether the characteristic of the tapered wall is above or below a threshold.

Disclosed is a method of condition monitoring a WTG (Wind Turbine Generator) comprising acts of collecting and storage of at least the following data sets together with their time stamps. Collection of generator power production measurements. Collection of mechanical status measurements. Collection of generator torque measurements. Collection of nacelle direction measurements. Collection of meteorological conditions measurements. The method compromises a further act of synchronizing the data sets. The invention also relates to a system for condition monitoring a WTG. The invention further relates to a system for visually inspecting a WTG.

Disclosed is a method of condition monitoring a WTG (Wind Turbine Generator) comprising acts of collecting and storage of at least the following data sets together with their time stamps. Collection of generator power production measurements. Collection of mechanical status measurements. Collection of generator torque measurements. Collection of nacelle direction measurements. Collection of meteorological conditions measurements. The method compromises a further act of synchronizing the data sets. The invention also relates to a system for condition monitoring a WTG. The invention further relates to a system for visually inspecting a WTG.