In a method of determining a radius or diameter of a train wheel, a camera mounted on a train acquires first and second images (pictures) of first and second objects spaced along a path being traveled by the train. Matches are then determined between the first and second objects appearing in the first and second acquired images and representations (pictures) of the first and second objects appearing in prerecorded images included in a track database that include corresponding first and second geographical locations. A distance L traveled by the train between the first and second geographical locations is determined and a sum C of electrical pulses generated by an encoder coupled to the train wheel during travel of the train the distance L is determined. Based on the distance L and the sum C, a diameter or radius of the wheel is determined.

An image acquisition unit for obtaining data to generate at least one three-dimensional representation of at least one underwater structure is disclosed. The image acquisition unit includes a unit body, a plurality of cameras, a first laser light device, and a second laser light device. The first laser light device can operate based on a first illumination setting. The second laser light device can operate based a second illumination setting. The first and second cameras can be configured to capture light during the first illumination setting and generate a first set of data representative of the first laser projecting on the at least one underwater structure at a predetermined scan rate. The third and fourth cameras can be configured to capture light during the second illumination setting and generate a second set of data representative of the second laser projecting on the at least one underwater structure at the predetermined scan rate.

A method for inspecting a spatial light modulator includes: performing such control that in an inspection target area in an array of mirror elements, the mirror elements in a first state in which incident light is given a phase change amount of 0 and the mirror elements in a second state in which incident light is given a phase change amount of 180 () become arrayed in a checkered pattern; guiding light having passed the inspection target area to a projection optical system with a resolution limit coarser than a width of an image of one mirror element, to form a spatial image; and inspecting a characteristic of the spatial light modulator from the spatial image. This method allows us to readily perform the inspection of the characteristic of the spatial light modulator having the array of optical elements.

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.

A system deposits a film on a substrate while determining mechanical stress experienced by the film. A substrate is provided in a deposition chamber. A support disposed in the chamber supports a circular portion of the substrate with a first surface of the substrate facing a deposition source and a second surface being reflective. An optical displacement sensor is positioned in the deposition chamber in a spaced-apart relationship with respect to a portion of the substrate's second surface located at approximately the center of the circular portion of the substrate. When the deposition source deposits a film on the first surface, a displacement of the substrate is measured using the optical displacement sensor. A processor is programmed to use the substrate displacement to determine a radius of curvature of the substrate, and to use the radius of curvature to determine mechanical stress experienced by the film during deposition.

A system deposits a film on a substrate while determining mechanical stress experienced by the film. A substrate is provided in a deposition chamber. A support disposed in the chamber supports a circular portion of the substrate with a first surface of the substrate facing a deposition source and a second surface being reflective. An optical displacement sensor is positioned in the deposition chamber in a spaced-apart relationship with respect to a portion of the substrate's second surface located at approximately the center of the circular portion of the substrate. When the deposition source deposits a film on the first surface, a displacement of the substrate is measured using the optical displacement sensor. A processor is programmed to use the substrate displacement to determine a radius of curvature of the substrate, and to use the radius of curvature to determine mechanical stress experienced by the film during deposition.

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.

A method and apparatus for characterizing a cutting tool edge from an image of the cutting tool edge. Chips, cracks and other tool edge defects are measured, providing an indication of the condition of a cutting tool edge.

A method and apparatus for characterizing a cutting tool edge from an image of the cutting tool edge. Chips, cracks and other tool edge defects are measured, providing an indication of the condition of a cutting tool edge.