Abstract: A handheld measurement tool with a display that can be defined by a user. The handheld measurement tool may be a portable measurement gauge (e.g. a digital caliper, digital “dial” gauge, height gauge, micrometer, indicator, etc.) that may be utilized for measuring precise physical dimensions of workpieces. The display may be independently modified according to a customer's individual needs for various precision measurement applications. A remote device (e.g. PC, laptop, tablet, smartphone, etc.) may be utilized for reconfiguring the display, wherein a user can select and modify display format arrangements on the remote device. When the remote device is coupled to the portable measurement gauge, the gauge display is reconfigured so as to have a similar appearance to the defined display format arrangement. In certain embodiments, voice commands may be reconfigured and used for controlling the gauge display.

Abstract: A chromatic point sensor system configured to compensate for potential errors due to workpiece material effects comprises a first confocal optical path including a longitudinally dispersive element configured to focus different wavelengths at different distances proximate to a workpiece; a second optical path configured to focus different wavelengths at substantially the same distance proximate to the workpiece; a light source connected to the first confocal optical path; a light source connected to the second optical path; a first confocal optical path disabling element; a second optical path disabling element; and a CPS electronics comprising a CPS wavelength detector which provides output spectral profile data. The output spectral profile data from the second optical path is usable to compensate output spectral profile data from the first confocal optical path for a distance-independent profile component that includes errors due to workpiece material effects.

Abstract: A chromatic point sensor system configured to compensate for potential errors due to workpiece material effects comprises a first confocal optical path including a longitudinally dispersive element configured to focus different wavelengths at different distances proximate to a workpiece; a second optical path configured to focus different wavelengths at substantially the same distance proximate to the workpiece; a light source connected to the first confocal optical path; a light source connected to the second optical path; a first confocal optical path disabling element; a second optical path disabling element; and a CPS electronics comprising a CPS wavelength detector which provides output spectral profile data. The output spectral profile data from the second optical path is usable to compensate output spectral profile data from the first confocal optical path for a distance-independent profile component that includes errors due to workpiece material effects.

Abstract: A method utilizing image correlation to determine position measurements in a machine vision system. In a first operating state, the machine vision system utilizes traditional scale-based techniques to determine position measurements, while in a second operating state, image correlation displacement sensing techniques are utilized to determine position measurements. The image correlation techniques provide for higher accuracy for measuring distances between features that are separated by more than one field of view. The user may toggle between the operating states through a selection on the user interface, and guidance may be provided regarding when the image correlation mode is likely to provide higher accuracy, depending on factors such as the distance to be measured and the characteristics of the surface being measured.

Abstract: Fast approximate focus operations providing an approximately focused image that is sufficiently focused to support certain subsequent inspection operations. The operations are particularly advantageous when used to provide images for successive inspection operations that predominate when inspecting planar workpieces. Improved inspection throughput is provided because, in contrast to conventional autofocus operations, the fast approximate focus operations do not acquire an image stack during a run mode as a basis for determining a best focused image. Rather, during learn mode, a representative feature-specific focus curve and a focus threshold value are determined and used during run mode to provide an approximately focused image that reliably supports certain inspection operations. In one embodiment, an acceptable approximately focused inspection image is provided within a limit of two focus adjustment moves that provide two corresponding images.

Abstract: A position sensing device comprises a light source that radiates diffuse source light along an optical axis direction to a detector, and a moving aperture arrangement positioned between the source and detector, to move perpendicular to the optical axis direction. The moving aperture arrangement comprises first and second limiting apertures, which angularly filter and transmit the diffuse source light to form a measurement spot on the detector. At least one signal output by the detector is indicative of a position of the movable member along a measurement axis. The angular intensity distribution of the angularly filtered rays of light which form the measurement spot is more consistent as a function of position along the measurement axis than the angular intensity distribution of the source light. The resulting consistent intensity distribution within the measurement spot throughout the measurement range enhances measurement linearity and accuracy.

Abstract: A chromatic point sensor (CPS) calibration object and characterizing data are provided. The calibration object comprises a flat base plane with steps extending from it. Step measurement points provided by the steps and base plane measurement points provided by portions of the base plane are intermingled along a measurement track. The characterizing data characterizes known heights of the measurement points. A calibration method acquires measurement data such that some base plane measurement points should be at nearly the same measurement distance and therefore have the same common mode errors relative to known base plane measurement point heights. If such base plane measurement points exhibit minimal error variations, then measurements for those and proximate measurement points may provide reliable calibration data. In contrast, error variations outside an expected range indicate unreliable measurements that should be screened or replaced by new calibration measurements.

Abstract: A chromatic point sensor (CPS) calibration object and characterizing data are provided. The calibration object comprises a flat base plane with steps extending from it. Step measurement points provided by the steps and base plane measurement points provided by portions of the base plane are intermingled along a measurement track. The characterizing data characterizes known heights of the measurement points. A calibration method acquires measurement data such that some base plane measurement points should be at nearly the same measurement distance and therefore have the same common mode errors relative to known base plane measurement point heights. If such base plane measurement points exhibit minimal error variations, then measurements for those and proximate measurement points may provide reliable calibration data. In contrast, error variations outside an expected range indicate unreliable measurements that should be screened or replaced by new calibration measurements.

Abstract: A low cost digital ruler with desirable ergonomic characteristics and accuracy. A low friction sliding position indicator includes a compliant element that forces its connection pads against the ruler's electronic scale contacts, to determining measurement positions. The position indicator includes an instrument receiving feature that engages a writing instrument and moves in conjunction with it, thereby measuring a line as it is drawn. A position indicator preload arrangement includes the compliant element, which is deflected to exert a preload that forces the sliding position indicator against a housing of the digital ruler. Alignment features of the position indicator and housing have cross sections that provide a self-aligning angled interference fit, which accurately aligns the sliding position indicator, under the action of the preload force. Misalignment constraint surfaces constrain the sliding position indicator in approximate alignment by, even if an external force overcomes the preload force.

Abstract: A low cost digital ruler with desirable ergonomic characteristics and accuracy. A low friction sliding position indicator includes a compliant element that forces its connection pads against the ruler's electronic scale contacts, to determining measurement positions. The position indicator includes an instrument receiving feature that engages a writing instrument and moves in conjunction with it, thereby measuring a line as it is drawn. A position indicator preload arrangement includes the compliant element, which is deflected to exert a preload that forces the sliding position indicator against a housing of the digital ruler. Alignment features of the position indicator and housing have cross sections that provide a self-aligning angled interference fit, which accurately aligns the sliding position indicator, under the action of the preload force. Misalignment constraint surfaces constrain the sliding position indicator in approximate alignment by, even if an external force overcomes the preload force.

Abstract: A method for writing or calibrating the scale of a scale-based position encoder. The scale is installed where it will be used to provide ongoing position measurements for a host system. The image correlation sensor is temporarily mounted proximate to the mounting position of the scale-based position encoder readhead on the host system, and is moved along the measuring axis relative to the scale, to provide corresponding displacement measurement information. The displacement measurement information is used to govern a scale writing process or a calibration process for the scale-based position encoder, such that the displacement measurement information at least partially governs the values of respective ongoing position measurements provided by the scale-based position encoder at respective positions along the measuring axis. A two-axis image correlation displacement sensor is advantageously used to detect and/or corrected various potential errors during the calibration or writing process.

Abstract: A hand-size structured-light three-dimensional metrology imaging system and method. Laser illumination stripes are scanned across a workpiece surface for obtaining z-height and x-coordinate information. A Scheimpflug configuration is used. Utilizing this configuration, a laser illumination stripe across a raised workpiece portion will be shown in a contour image at the image sensor in a focused manner, such that the offsets along the contour image line due to the raised portions of the workpiece surface can be accurately converted to a z-height measurement. The y-axis positions associated with each of the contour images, used for reassembling the information from the contour images into a surface map for the workpiece, may be determined without the need for a position sensor, by including a reference object in the contour images.

Abstract: A handheld metrology imaging system and method. In one embodiment, the device may comprise an imaging portion, a display portion, a signal processing and control portion, an image capture activation element and a user interface. The user interface may comprise user adjustable video measurement tools configurable relative to an image on the display portion, and video tool adjusting elements. Measurement functions are provided that operate to provide a dimensional measurement result based on the configurations of the video measurement tools. The handheld device can be used to measure not only the normal parts which have traditionally been measured by conventional handheld tools such as a caliper or micrometer, but also very small or flat parts that are difficult to measure with conventional tools.

Abstract: A hand-size structured-light three-dimensional metrology imaging system and method. Laser illumination stripes are scanned across a workpiece surface for obtaining z-height and x-coordinate information. A Scheimpflug configuration is used. Utilizing this configuration, a laser illumination stripe across a raised workpiece portion will be shown in a contour image at the image sensor in a focused manner, such that the offsets along the contour image line due to the raised portions of the workpiece surface can be accurately converted to a z-height measurement. The y-axis positions associated with each of the contour images, used for reassembling the information from the contour images into a surface map for the workpiece, may be determined without the need for a position sensor, by including a reference object in the contour images.

Abstract: A handheld metrology imaging system and method. In one embodiment, the device may comprise an imaging portion, a display portion, a signal processing and control portion, an image capture activation element and a user interface. The user interface may comprise user adjustable video measurement tools configurable relative to an image on the display portion, and video tool adjusting elements. Measurement functions are provided that operate to provide a dimensional measurement result based on the configurations of the video measurement tools. The handheld device can be used to measure not only the normal parts which have traditionally been measured by conventional handheld tools such as a caliper or micrometer, but also very small or flat parts that are difficult to measure with conventional tools.

Abstract: A method and apparatus for measuring a wavelength-related characteristic of a radiation source is provided. Two beams travel through substantially identical filters at different angles, which produces two different output signals that behave similarly with respect to power and/or temperature variations. In various embodiments, the two beams are filtered through two portions of a single filter. A diffraction grating may be mounted to the filter to split incident radiation into first and second beams. The beams thus travel through the filter at different angles, to produce two output signals that can be combined to compensate for common-mode errors as well as power variations. Extremely small size and high-resolution may be achieved. Single or multiple detectors may also be used.

Abstract: A position error correcting, or reducing, method and system used in an image-correlation system which obtains an error function generally reflecting an error occurring over a nominal reference image update length and an error occurring at a first frequency and various other system errors. The error can be compared to a first reference to fit the position error. In various embodiments, parameters of an error function can be varied in fitting the error function to the first reference. The obtained error function can then be used to determine the position error and render more accurate the image correlation system. In one exemplary implementation, the first frequency is related to a pixel pitch and the nominal reference image update length related to the distance between reference image changes is the maximum usable reference image update length.

Abstract: A position sensor using a novel optical path array (OPA) element, an angle-selective spatial filter, and an imaging array is capable of measuring the translation and orientation relative to a target member in X, Y, Z, yaw, pitch, and roll (“6D”) simultaneously, and with high precision. A target member includes an array of target points surrounded by a contrasting surface. The position sensor uses the OPA element in combination with the angle-selective spatial filter in a target point imaging arrangement such that the imaging array of the position sensor only receives light rays that enter the OPA element according to an operable cone angle ?. Accordingly, each target point generally produces a ring-shaped image having a size on the imaging array that varies with the Z position of each target point. The X-Y position of each target point image on the imaging array varies with the X-Y position of each target point.

Abstract: A reference image updating method and apparatus used in an image-correlation system which updates a reference image when predetermined control parameters are met. An image corresponding to a displacement of a surface is captured and stored. A reference image and the captured image are compared at different offsets in a displacement direction. When the displacement falls within set predetermined displacement values or a predetermined value for a sample time that corresponds to the displacement, then the reference image is updated. By updated the reference image in this manner, systematic errors are prevented from accumulating thereby significantly removing systematic errors in the image-correlation system.

Abstract: After one or both of a pair of images are obtained, an auto-correlation function for one of those images is generated to determine a smear amount and possibly a smear direction. The smear amount and direction are used to identify potential locations of a peak portion of the correlation function between the pair of images. The pair of images is then correlated only at offset positions corresponding to the one or more of the potential peak locations. In some embodiments, the pair of images is correlated according to a sparse set of image correlation function value points around the potential peak locations. In other embodiments, the pair of images is correlated at a dense set of correlation function value points around the potential peak locations. The correlation function values of these correlation function value points are then analyzed to determine the offset position of the true correlation function peak.