Abstract: A method of determining whether a part satisfies tolerance criteria includes making a multiplicity of measurements of the part, reducing the number of measured points to a number of boundary points that define a boundary within which all measured points are encompassed and comparing the boundary to a tolerance limit of a normal surface to determine whether the part conforms to the tolerance.

Abstract: An illumination system shares portions of an objective of an optical inspection system. A plurality of beam-shaping optics collects light from a plurality of effective light sources and directs the light through a portion of the objective for illuminating an object under inspection. The objective includes a front relay lens, a rear relay lens, and an objective stop disposed between the front and rear relay lenses for collecting light scattered from the object and forming an image of the object with the collected light. The beam-shaping optics, which surround the objective stop, are arranged together with the associated effective light sources for non-uniformly distributing light within a range of angles required for illuminating the object.

Abstract: A method of forming a combined feature boundary based on boundaries of first and second overlapping features includes dividing the boundaries of the first and second overlapping features into line segments of known shape, identifying crossing points formed by the line segments, calculating parametric coordinates of the crossing points, and determining a sequence of crossing point evaluation based on the parametric coordinates. The method also includes calculating a first cross product based on the line segments forming a first crossing point in the determined sequence, and choosing a first path of the combined feature boundary according to a mathematical sign of the first cross product, the first path extending from the first crossing point to the second crossing point in the determined sequence.

Abstract: A machine vision system includes a table having a fixture for supporting an object under inspection above the table, a gantry supporting a camera further above the table, a docking station, and a profile light movable together with the gantry between an inspection position beneath the object and a docking position next to the docking station. Fittings are provided for releasably securing the profile light to the gantry and for releasably securing the profile light to the docking station. The profile light can be disengaged from the gantry and engaged with the docking station for moving the profile light to the docking position or disengaged from the docking station and reengaged with the gantry for moving the profile light to the inspection position.

Abstract: A graphical representation of a feature and associated tolerance includes a graphical representation of a nominal definition of the feature; and a graphical representation of the tolerance zones, derived from the nominal definition of the feature.

Abstract: An optical metrological system having a heat-generating light source coaxially mounted near a heat-sensitive lens. The system uses a temperature sensor to monitor the lens temperature and a heating element to heat the lens such that the lens operating temperature is greater than a maximum operating temperature of the light source in order to stabilize the focal length of the lens.

Abstract: Measurement data collected within a measurement frame of reference is fitted to geometric tolerance zones having regard for the uncertainties of the measurement. Geometric freedoms for fitting the measurement data are exploited to fit uncertainty zones associated with the measurement data within the tolerance zones. Typically, the measurement data is multidimensional and the uncertainty zones have different sizes.

Abstract: An actuator for selectively extending and retracting a probe in a measuring instrument comprises an actuator body, a carriage having a first aperture slidably attached to the body, and a second aperture receiving a probe holder having a probe. The first aperture of the carriage, which surrounds the actuator body, includes a first plurality of magnets disposed around an inner circumference of the aperture. The actuator body includes a lead screw, a round lead screw nut mated with the lead screw, and a second plurality of magnets arranged on a periphery of the lead screw nut, generally aligned with the first plurality of magnets. The magnets are arranged so that the carriage may be displaced with respect to the actuator body a sufficient amount that the magnets do not significantly restrain the further movement of the carriage.

Abstract: This high performance front objective lens system intended primarily for use with a video inspection apparatus has a first lens set in the form of a doublet, with a second lens set intermediate the first lens set and the imaging plane. The second lens set includes a doublet and an adjacent lens. The overall system has an effective focal length of 50 mm, a front focal length of 38.75 mm, and a numerical aperture greater than 0.2. Further, the material of the doublets is chosen to have a small, gradual transition in index between the elements of the lens and the cement, minimizing back reflections and thereby eliminating the need for index matching coatings on the cemented surfaces of the doublets. Finally, the imaging plane of the system matches that of standard ring lights used with video inspection apparatus.

Abstract: An optical comparator arranged for rear projection onto a viewing screen combines an optical projector that projects an optical image of a test part under inspection onto the viewing screen with a video projector that projects an optical image of a pixilated template pattern containing illustrated specifications of the test part onto the same viewing screen. The images of the test part and the pixilated template pattern are projected concurrently onto the viewing screen for visually comparing the form of the test part against its specified form.

Abstract: An adapter and method for through the lens (TTL) laser range sensor probes enables use of a TTL probe of a given exit pupil size to be used with a shared objective lens requiring a entrance pupil size, as entered from the laser range sensor, that is different from the TTL probe exit pupil size. Embodiments of the adapter include optics, such as a first lens and a resolving second lens that expand or contract the TTL laser radiation depending on whether the first lens is a diverging, a negative focal length lens, or a converging, positive focal length lens, and the second lens is converging or diverging, respectively, in a Galilean arrangement. Embodiments also provide a Keplerian arrangement, can function with non-collimated radiation, and can include mirrors to yield a more compact adapter. Additional embodiments include at least one adjustable lens element between the first and second lenses, the at least one adjustable lens element being connected to an actuator for movement along the optical path.

Abstract: An autofocus system and method that includes a controllable light source having at least two selectively activated substantially monochromatic output wavelengths adapted for illuminating an object; a camera receiving light from said light source reflected from a portion of said object and generating output signals responsive to said received light; a controller connected to said camera and said controllable light source for positioning said camera and sequentially illuminating a first portion of the object with at least two selectively activated substantially monochromatic output wavelengths, moving the camera to a second position and sequentially illuminating a second portion of the object with at least two selectively activated substantially monochromatic output wavelengths; and a data processor connected to said camera and receiving said output signals and for each portion, comparing the output signals associated with each wavelength and determining a focus parameter from said comparison.

Abstract: A distance detecting arrangement employs at least two sensors having different ranges and resolutions of operation. Embodiments disclosed contemplate at least four modes of operation. In a first mode, only one sensor is employed. In a second mode, a longer range and lower resolution sensor is employed until a threshold value of distance is reached, at which point a shorter range and higher resolution sensor is employed. In a third mode, both the longer range and shorter range sensors are employed simultaneously. In a fourth mode, a low resolution profile is used to rescan the object with the high resolution sensor to provide a high resolution profile measurement. Embodiments facilitate the method disclosed by including a beam redirecting apparatus and preferably include a servo position system that can move the sensors and the object relative to each other.

Abstract: An illumination system using, in place of a more typical beam splitter, two right angle triangular prisms that are aligned to each other along their respective hypotenuses to form a cube, but without any reflective materials being used at their interface, and with the two halves separated by some distance so as to create an open/air gap between the two halves. When the upper/lower cube faces are normal to an optical axis of the illumination system, the cube structure reflects virtually all of the illumination from a transverse illumination source using total internal reflection so that said illumination is reflected out of the cube along the system's optical axis. However, rotating the cube structure past the critical angle eliminates total internal reflection and allows the cube to transmit almost all illumination entering the cube out of the cube parallel to the system's optical axis.

Abstract: A partial coherence interferometer incorporates a focusing system for resolving measurement ambiguities. A focus-sensing beam is directed through a common objective with the measurement beam of the interferometer for conveying the beams to and from a test surface. An unambiguous measuring range is equated to a predetermined range of focusing errors.

Abstract: A method of forming a combined feature boundary based on boundaries of first and second overlapping features includes dividing the boundaries of the first and second overlapping features into line segments of known shape, identifying crossing points formed by the line segments, calculating parametric coordinates of the crossing points, and determining a sequence of crossing point evaluation based on the parametric coordinates. The method also includes calculating a first cross product based on the line segments forming a first crossing point in the determined sequence, and choosing a first path of the combined feature boundary according to a mathematical sign of the first cross product, the first path extending from the first crossing point to the second crossing point in the determined sequence.

Abstract: An optical metrological system having a heat-generating light source coaxially mounted near a heat-sensitive lens. The system uses a temperature sensor to monitor the lens temperature and a heating element to heat the lens such that the lens operating temperature is greater than a maximum operating temperature of the light source in order to stabilize the focal length of the lens.

Abstract: An optical metrological system having a heat-generating light source coaxially mounted near a heat-sensitive lens. The system uses a temperature sensor to monitor the lens temperature and a heating element to heat the lens such that the lens operating temperature is greater than a maximum operating temperature of the light source in order to stabilize the focal length of the lens.

Abstract: The invention provides a source of illumination comprising a base having mounted thereon at least one light-emitting diode light source, a parabolic reflector mounted on the base and surrounding the at least one light-emitting diode, and a transmissive diffuser at the narrow end of the parabolic reflector.

Abstract: A partial coherence interferometer incorporates a focusing system for resolving measurement ambiguities. A focus-sensing beam is directed through a common objective with the measurement beam of the interferometer for conveying the beams to and from a test surface. An unambiguous measuring range is equated to a predetermined range of focusing errors.