Abstract: An optical imaging system for a dimensional measuring machine including a digital sensor having an array of addressable pixels, a lens system that provides for forming an image of a test object on the digital sensor, and a variable size aperture of the lens that changes an f-number of the lens system for imaging points of the test object on the digital sensor at different spot sizes. An aperture controller varies the aperture size. An image controller groups contiguous clusters of one or more of the pixels having a common output such that the number of pixels within each of the clusters having a common output can be varied.

Abstract: A video measurement system includes an imaging system, a reticle projector for projecting an image of a reticle through the imaging system onto the test object, and a camera for capturing images of the test object together with the reticle image projected onto the test object through the imaging system. A selective reflector reflects the reticle image into the camera from a position along the imaging system in advance of the test object. A mode selector is operable in a first mode for directing the reticle image to the test object and from the test object to the camera and is operable in a second mode for directing the reticle image to the selective reflector and from the selective reflector to the camera.

Abstract: A video measurement system includes an imaging system, a reticle projector for projecting an image of a reticle through the imaging system onto the test object, and a camera for capturing images of the test object together with the reticle image projected onto the test object through the imaging system. A selective reflector reflects the reticle image into the camera from a position along the imaging system in advance of the test object. A mode selector is operable in a first mode for directing the reticle image to the test object and from the test object to the camera and is operable in a second mode for directing the reticle image to the selective reflector and from the selective reflector to the camera.

Abstract: An optical inspection system for capturing images of backlit test objects on a detector at two or more aperture settings includes a telecentric imaging system having a first setting associated with a first size aperture stop and a second setting associated with a second larger size aperture stop. An illumination system includes a substage illuminator incorporating (a) a first set of one or more light sources surrounded by a first barrier that defines a first size aperture stop of the illumination system and (b) a second set of one or more light sources located beyond the first barrier and surrounded by a second barrier that defines a second larger size aperture stop of the illumination system. The first size aperture stop of the illumination system images to the first size aperture stop of the telecentric imaging system at the first setting and the second larger size aperture stop of the illumination system images to the second larger size aperture stop of the telecentric imaging system at the second setting.

Abstract: A method of focusing a telecentric imaging system (30), particularly as a part of a measuring machine (10) includes measuring an image of a feature (25) of an object (24) through the telecentric imaging system (30) in a telecentric operating mode and measuring an image of the feature (25) of the object (24) through the telecentric imaging system (30) in a non-telecentric operating mode. A value is acquired characterizing a function by which the size of the imaged feature varies in the non-telecentric mode with the relative displacement of the object (24) through the depth of field (D). The measures of the image of the feature (25) of the object (24) in the telecentric and non-telecentric modes are related to each other and to the acquired value as an estimate of a relative displacement of the object (24) from the best focus position.

Abstract: A method of focusing a telecentric imaging system (30), particularly as a part of a measuring machine (10) includes measuring an image of a feature (25) of an object (24) through the telecentric imaging system (30) in a telecentric operating mode and measuring an image of the feature (25) of the object (24) through the telecentric imaging system (30) in a non-telecentric operating mode. A value is acquired characterizing a function by which the size of the imaged feature varies in the non-telecentric mode with the relative displacement of the object (24) through the depth of field (D). The measures of the image of the feature (25) of the object (24) in the telecentric and non-telecentric modes are related to each other and to the acquired value as an estimate of a relative displacement of the object (24) from the best focus position.

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: 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: 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: The substage illuminator is in the form of a housing having therein an opening disposed to register with the underside of a workpiece that is being inspected by optical gaging apparatus which is disposed to overlie the workpiece and which has an image inlet aperture registering with the opening in the substage housing. A collimating lens is mounted in the opening of the housing beneath an anti-reflection filter, and a light source which is mounted in or connected to the housing, projects a circular beam of light successively through the collimator lens and filter toward the underside of the inspected workpiece. The light source may be in the form of a plurality of radially spaced, circular arrays of LED's that can be selectively illuminated to control the diameter of the beam emitted thereby, or the source may comprise an L.C.D. aperture generator which may be energized to produce light beams of selectively different diameters.