An end mill inspection device, which inspects an end mill having a blade part formed in a curved convex shape or an arc shape, includes: an imaging data acquisition unit that acquires imaging data obtained by capturing an image of a blade part of the end mill by an imaging unit; a contour extraction unit that extracts the contour of the blade part on the basis of the imaging data acquired by the imaging data acquisition unit; and a curvature radius calculation unit that calculates a curvature radius of the contour on the basis of the contour of the blade part extracted by the contour extraction unit.

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.

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.

Reference and test waves are directed in a common path mode in a fiber tip diffraction interferometer. A first fiber can be used to generate the reference wave and a second fiber can be used to generate the test wave. Each fiber can include a single mode fiber tip that defines a wedge at an end without a coating on end surface or a tapered fiber tip. The fiber tip diffraction interferometer can include an aplanatic pupil imaging lens or system disposed to receive both the test wave and the reference wave and a sensor configured to receive both the test wave and the reference wave.

Reference and test waves are directed in a common path mode in a fiber tip diffraction interferometer. A first fiber can be used to generate the reference wave and a second fiber can be used to generate the test wave. Each fiber can include a single mode fiber tip that defines a wedge at an end without a coating on end surface or a tapered fiber tip. The fiber tip diffraction interferometer can include an aplanatic pupil imaging lens or system disposed to receive both the test wave and the reference wave and a sensor configured to receive both the test wave and the reference wave.

Provided is a method for evaluating production precision of a spectacle lens having micro convex segments protruding from a convex surface on an object side of the spectacle lens, including measuring a shape of the convex surface of the spectacle lens; setting an actual device virtual model including a spectacle lens model based on the measured shape and an eyeball model; performing ray tracing calculation on the actual device virtual model and specifying an actual device convergence position where light rays converge on an front side of a retina of the eyeball model; and evaluating production precision of the spectacle lens on the basis of the actual device convergence position.

Provided is a method for evaluating production precision of a spectacle lens having micro convex segments protruding from a convex surface on an object side of the spectacle lens, including measuring a shape of the convex surface of the spectacle lens; setting an actual device virtual model including a spectacle lens model based on the measured shape and an eyeball model; performing ray tracing calculation on the actual device virtual model and specifying an actual device convergence position where light rays converge on an front side of a retina of the eyeball model; and evaluating production precision of the spectacle lens on the basis of the actual device convergence position.

The disclosure relates to a measuring method and a measuring device for measuring a radius of an optical element based on a computer-generated hologram, and belongs to the field of photoelectric technology detection. The present disclosure is characterized in that two conjugated wave surfaces, i.e. a confocal wavefront and a cat's eye wavefront, are simultaneously generated by one piece of computer-generated hologram, and at the same time, interferograms at the cat's eye position and at the confocal position are obtained and surface shape parameters are measured, and the radius of an optical element is solved according to the measurement result.

The disclosure relates to a measuring method and a measuring device for measuring a radius of an optical element based on a computer-generated hologram, and belongs to the field of photoelectric technology detection. The present disclosure is characterized in that two conjugated wave surfaces, i.e. a confocal wavefront and a cat's eye wavefront, are simultaneously generated by one piece of computer-generated hologram, and at the same time, interferograms at the cat's eye position and at the confocal position are obtained and surface shape parameters are measured, and the radius of an optical element is solved according to the measurement result.

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.