Abstract: The attenuation and other optical properties of a medium are exploited to measure a thickness of the medium between a sensor and a target surface. Disclosed herein are various mediums, arrangements of hardware, and processing techniques that can be used to capture these thickness measurements and obtain three-dimensional images of the target surface in a variety of imaging contexts. This includes general techniques for imaging interior/concave surfaces as well as exterior/convex surfaces, as well as specific adaptations of these techniques to imaging ear canals, human dentition, and so forth.

Abstract: The attenuation and other optical properties of a medium are exploited to measure a thickness of the medium between a sensor and a target surface. Disclosed herein are various mediums, arrangements of hardware, and processing techniques that can be used to capture these thickness measurements and obtain three-dimensional images of the target surface in a variety of imaging contexts. This includes general techniques for imaging interior/concave surfaces as well as exterior/convex surfaces, as well as specific adaptations of these techniques to imaging ear canals, human dentition, and so forth.

Abstract: The invention discloses a vehicle dynamic measurement device for comprehensive parameters of rail wear, which comprises a vision sensor, a computer and a milometer. A high-speed image acquisition card and a measurement module are installed in the computer. The vision sensor comprises imaging system for rail cross-section and a raster projector which can project more than one light plane perpendicular to the measured rail. The measurement module is used for calculating vertical wear, horizontal wear, the amplitude and wavelength of corrugation wear. The invention also discloses a vehicle dynamic measurement method for comprehensive parameters of rail wear. The invention can increase the sampling rate of image sensing and acquisition hardware equipment with no need of improving the performance of it, thereby satisfy high-speed on-line dynamic measurement requirements for corrugation wear, and the amplitude and wavelength of corrugation wear can be calculated more precisely.

Abstract: An object of the present invention is to provide a detection device of a planar area, which suppresses matching of luminance values in areas other than a planar area, and non-detection and erroneous detection of the planar area arising from an error in projection transform. The detection device of a planar area includes an image obtaining section for obtaining a left image 100 and a right image 110; a planar area aligning section 30 for setting given regions of interest to the obtained left image 100 and the right image 110, and through use of a geometric transform function that matches the region of interest of the right image with the region of interest of the left image, performing geometric transform to generate a geometric transform image 130; and a planar area detecting section 55 for detecting a planar area 140 based on the geometric transform image 130 and the region of interest of the right image 110.

Abstract: A method and system collects and manipulates information from various sources for the purpose of determining the location of loads of material in a bulk material storage container and tracing the number and identity of bulk material sources, such as farms or processing plants, for loads located within a bulk material storage container. Such production source information is thus uniquely associated with a particular non-liquid bulk material load. Surface mapping of a surface of bulk material stored in a storage container is performed before and after material is added to the container, and are used to determine position of loads within the storage container. Embodiments of the present invention, using knowledge of the position of loads within the container, may be used for the purposes of preplanning and enhancing blended load-out batches.

Abstract: In a method for aligning three-dimensional shape data obtained by performing a three-dimensional measurement of an object, photogrammetry of the object with a target mark is performed to obtain a three-dimensional position and a normal vector of the target mark by a calculation, and the three-dimensional measurement of the object is performed to obtain a three-dimensional position and a normal vector of the target mark. Then, determined is a correspondence between the three-dimensional position of the target mark obtained by the photogrammetry and the three-dimensional position of the target mark obtained by the three-dimensional measurement, by using the three-dimensional position and the normal vector of the target mark obtained by the photogrammetry and those of the target mark obtained by the three-dimensional measurement, and three-dimensional shape data obtained by the three-dimensional measurement is aligned based on the correspondence between the three-dimensional-positions of the target marks.

Abstract: A scanning system for confocal scanning of an object, comprising a light source (1), imaging optics (4) for focusing the light (5) radiated from the light source (1) onto the object (6) to be scanned, and further comprising an image detector (10) for detecting the light (7) from an object point (6?) backscattered from the object (6) and passing through the same imaging optics (4).

Abstract: A measuring method, comprising a step of drawing a line on a surface such as ground surface, a step of performing measurement along the line on a predetermined measurement range including the line, a step of acquiring an image of a range including the predetermined measurement range as an image data, a step of superimposing the image data on a measurement data, and a step of calculating a measurement data of the line from line position in the image data and from the measurement data near the line.

Abstract: The invention provides an examination apparatus including an objective optical system for positioning a focal point inside a specimen mounted on a stage; an image-acquisition apparatus for detecting light emitted in different optical-axis directions from the vicinity of the focal point inside the specimen and collected by the objective optical system to acquire a plurality of pieces of image information; and a three-dimensional image forming unit for forming a three-dimensional image of a light-emitting site in the vicinity of the focal point based on the plurality of pieces of image information acquired by the image-acquiring apparatus.

Abstract: A method for determining a mobility of foot comprising: measuring at least a portion of a shape of the foot under a first weight load; measuring the at least the portion of the shape of the foot under a second weight load; and comparing the measurement under the first weight load to the measurement under the second weight load, thereby determining a mobility of at least the portion of the foot.

Abstract: A system for providing shape determination of a planar or quasi-planar surface is disclosed. The system includes a number of targets located on the surface and one or more sensor devices. The sensor devices are configured to monitor the targets and obtain information relating to deflections normal to the plane of the surface. The sensor devices are mounted close to each other and the line-of-sight of each sensor device is at a shallow angle to the plane of the surface. The system further includes processing logic configured to execute a shape reconstruction algorithm based on the information to determine the shape of the surface.

Abstract: The present invention relates to a method and a system for optical imaging of an object in transmission configuration. The method and system obtain contour coordinates of the object using source/detector configurations references and acquire optical data from a region of interest (ROI) of the object. Then, the method and system apply a weighting factor to said optical data as a function of the contour coordinates, and reconstruct an image of the ROI using the weighted optical data and photon diffusion equation.

Abstract: The invention provides for surface mapping of in-vivo imaging subjects using a single camera and a moveable stage on which a subject animal for in-vivo imaging is placed. Images are taken and the stage is moved by known amounts along the optical axis, and the heights of individual features on the subject are determined through analysis of focus, given the known stage displacement. Alternatively, height of sub-regions of the subject are determined through analysis of focus. A mesh or other surface can be constructed from individual features, to provide a surface map of the subject. Accuracy of 0.5 mm or better can be attained for mice and similarly sized subjects.

Abstract: The invention provides for surface mapping of in-vivo imaging subjects using a single camera and an illuminator that projects a plurality of targets such as spots on the subject. By limiting the depth-of-field of the camera lens, or of the illuminator optics, or both, a spatial plane is defined in which the spots are most sharply in focus. Controlled displacement of this plane relative to the subject is achieved through movement of the mechanical stage on which a subject is placed; or through movement of the best-focus plane by adjustment of the camera, lens, or illuminator optics. Images are taken at several relative positions of the best-focus plane and the subject, and the height of individual points on the subject is determined through analysis of focus, given the known displacements. A mesh or other surface can be constructed from individual point locations, to provide a surface map of the subject. Accuracy of 0.5 mm can be readily attained for mice and similarly sized subjects.

Abstract: Described is a multiple channel interferometric surface contour measurement system. The measurement system includes a multiple channel interferometer projector, a digital camera and a processor. The projector includes two or more interferometer channels. Each channel has an optical axis spatially separate from the optical axes of the other channels. Each channel projects a fringe pattern onto the surface of an object to be measured. Image data for the fringe patterns projected on the object surface are acquired by the digital camera. The processor controls the projection of the fringe patterns of different spatial frequencies, adjusts the phase of each fringe pattern and generates surface contour data in response to the camera image data. The multiple channel interferometric surface contour measurement system provides numerous advantages over conventional single channel interferometric systems, including reduced sensitivity to optical noise, improved stability and increased measurement accuracy.

Abstract: Complex multidimensional datasets generated by digital imaging spectroscopy can be organized and analyzed by applying software and computer-based methods comprising sorting algorithms. Combinations of these algorithms to images and graphical data, allow pixels or features to be rapidly and efficiently classified into meaningful groups according to defined criteria. Multiple rounds of pixel or feature selection may be performed based on independent sorting criteria. In one embodiment sorting by spectral criteria (e.g., intensity at a given wavelength) is combined with sorting by temporal criteria (e.g., absorbance at a given time) to identify microcolonies of recombinant organisms harboring mutated genes encoding enzymes having desirable kinetic attributes and substrate specificity. Restriction of the set of pixels analyzed in a subsequent sort based on criteria applied in an earlier sort (“sort and lock” analyses) minimize computational and storage resources.

Abstract: A re-calibration method and device for a three-dimensional visual sensor of a robot system, whereby the work load required for re-calibration is mitigated. While the visual sensor is normal, the visual sensor and a measurement target are arranged in one or more relative positional relations by a robot, and the target is measured to acquire position/orientation information of a dot pattern etc. by using calibration parameters then held. During re-calibration, each relative positional relation is approximately reproduced, and the target is again measured to acquire feature amount information or position/orientation of the dot pattern etc. on the image. Based on the feature amount data and the position information, the parameters relating to calibration of the visual sensor are updated. At least one of the visual sensor and the target, which are brought into the relative positional relation, is mounted on the robot arm.

Abstract: A system to process requests for wafer structure profile determination from optical metrology measurements off a plurality of structures formed on one or more wafer includes a diffraction signal processor, a diffraction signal distributor, and a plurality of profile search servers. The diffraction signal processor is configured to obtain a plurality of measured diffraction signals of the plurality of structures. The diffraction signal distributor is coupled to the diffraction signal processor. The diffraction signal processor is configured to transmit the plurality of measured diffraction signals to the diffraction signal distributor. The plurality of profile search servers is coupled to the diffraction signal distributor. The diffraction signal distributor is configured to distribute the plurality of measured diffraction signals to the plurality of profile search servers.

Abstract: A color sorting apparatus capable of displaying images of granules picked up by a CCD sensor on a panel and performing sensibility control of defective granules while observing the displayed images is provided. The color sorting apparatus comprises a contour processor for outputting contour binary data from the picked-up images and a contour threshold, a first defective determination circuit for outputting the defective part of the granule having a predetermined area or more of part exceeding a first threshold in the form of first defective pixel binary data, and a second defective determination circuit for outputting the defective part of the granule having a part exceeding a second threshold being greater than the first threshold in the form of second defective pixel binary data. The first defective pixel binary data are displayed on a monitor for thin coloration. The second defective pixel binary data are displayed on a monitor for partial coloration.

Abstract: A method of optimizing the predictability of a vision correction procedure by comparing historical data, including the vision defect, the correction method and outcome, in terms of wavefront aberrations with a patient's condition to select an acceptable procedure. The patient's eye is examined and an optical model is created and compared to the historical data to select an acceptable procedure. The procedure is performed and the outcome is included in the data base.

Abstract: There is disclosed a method and computer program product for estimating a measure of the quality of the received signal in a computer simulation of an optical transmission system, wherein the simulation includes additive optical noise generated by components within the transmission system. The method and product are able to account for non-Gaussian statistics of noise fluctuations observed in the receivers of optical communications systems, in order to provide for the more accurate simulation of system performance than may be the case using prior art methods based on Gaussian approximation.

Abstract: The numerical analysis system of the invention analyzes the dynamical state of the compressible fluid employing Hybrid Grid Adaptation Method by Finite Volume Method. The initial grid data are created by way of free combination of tetrahedral cells, hexahedral cells and pentahedral cells. The divide-delete index is calculated according to the density of the fluid in each cell. A triangular face of the cell is divided into triangular faces and the quadrilateral face is divided into quadrilateral faces when the cell is divided. The cell is divided only when three conditions are satisfied. The first condition is that the volume of the cell is greater than the minimum volume. The second is that the dividing level of the cell is not the maximum level. The third is that the divide-delete index is greater than the dividing threshold.

Abstract: The present invention provides an image input apparatus into which a three-dimensional image as well as a two-dimensional image can be easily input. This image input apparatus includes an image pick-up unit, a projector unit, and a mover unit. The projector unit projects a predetermined projection light pattern onto an image object, and the image pick-up unit picks up the projection image containing distortions of the projection light pattern. The relative position between the projector unit and the image pick-up unit is fixed. The mover unit moves the image pick-up unit relatively with the projector unit, so that the image pick-up unit can pick up a plurality of projection images at different image pick-up locations.

Abstract: The present invention is in the area of tracking objects with systems such as correlation, gridlocking, optical correlation, and combinations thereof. Embodiments encompass systems of process and/or equipment to correlate objects and gridlock sensors with images based upon track data from sensors. In many of the embodiments the sensors may comprise radars, global positioning systems, laser target designators, seismic sensors or systems of seismic sensors comprising hydrophones and geophones, and other similar systems. While embodiments may comprise an optical correlator, many embodiments perform one or more analyzes statistically. Embodiments may refine coordinate transformations for the sensors and may account for errors by comparing a full or partial history of the track data associated with the same object from the same sensor. Further, many embodiments comprise software that can execute on a laptop, desktop, or similar computer.

Abstract: An apparatus for registering a series of video images of a spherical or quasi-spherical surface subject to movement relies on projecting at least four diffusely scattering spots of light on the surface in a preferred angular manner, and monitoring the movement of images of the light spots relative to a reference image of the light spots.

Abstract: The present invention is in the area of tracking objects with systems such as correlation, gridlocking, optical correlation, and combinations thereof. Embodiments encompass systems of process and/or equipment to correlate objects and gridlock sensors with images based upon track data from sensors. In many of the embodiments the sensors may comprise radars, global positioning systems, laser target designators, seismic sensors or systems of seismic sensors comprising hydrophones and geophones, and other similar systems. While embodiments may comprise an optical correlator, many embodiments perform one or more analyses statistically. Embodiments may refine coordinate transformations for the sensors and may account for errors by comparing a full or partial history of the track data associated with the same object from the same sensor. Further, many embodiments comprise software that can execute on a laptop, desktop, or similar computer.

Abstract: A photodetector device and a process for manufacturing the same are described. The photodetector device comprises a doped semiconductor substrate; an intrinsic semiconductor material layer formed over the substrate, for absorbing incident light; an upper semiconductor material layer doped with the opposite type to the substrate, formed on a portion of the intrinsic semiconductor material layer to allow at least a portion of the incident light to directly enter the intrinsic semiconductor material layer; an upper electrode formed in a predetermined pattern on the upper semiconductor material layer, the upper electrode electrically connected to the upper semiconductor material layer; and a lower electrode electrically connected to the substrate, wherein a portion of the intrinsic semiconductor material layer constitutes at least a part of a photo-receiving surface.

Abstract: The invention concerns a method for acquiring an image by oversampled push-broom scanning from a satellite-borne vehicle or aircraft carrying at least a load transfer sensor bar, characterised in that it consists in controlling the attitude and the vehicle rolling, pitching and yawing angular speeds such that the longitudinal and lateral ground speeds of the bar verify: (a), (b) in which Vref=P/Ti, P being the bar ground step, Ti the sampling period, and m and l two whole numbers.

Abstract: A system and method for performing corneal ablation or reshaping with a laser in order to correct aberrations in the optical system of the eye utilizes a wavefront sensor which defines a wavefront correction for the eye and then, based upon that defined wavefront correction, drives a digital micromirror device (DMD) which modulates a laser beam to the eye to perform the correction. As the DMD is a 2-D array of individually controlled mirrors, and the wavefront sensor analysis can provide a sequence of two dimensional arrays of values which together define the wavefront correction for the eye, the combination of the two produces a method for correcting the corneal surface.

Abstract: A device for determining at least a portion of a convex boundary of an object and a method of operating the same to determine the convex boundary or motion thereof. In one embodiment, the device includes: (1) first, second and third sensors, locatable about the object, that scan the object in corresponding first, second and third dimensions and produce signals indicating boundary sections in corresponding first, second and third planes and (2) a boundary integrator, coupled to the first, second and third sensors, that combines the signals to develop therefrom the convex boundary.

Abstract: A measuring instrument (100) and a method for measuring features (19) on a substrate (9) are described. The measuring instrument (100) has a support element (15) that is provided opposite the substrate (9). Mounted on the support element (15) is a nonoptical measurement device (23) with which a measurement of the features (19) of the substrate (9) is performed under ambient air pressure. The nonoptical measurement device (23) can be configured, for example, as an AFM (24) or an electron beam lens (40). Furthermore, in addition to the nonoptical measurement device (23), an optical lens (10) can be provided that is used for rapid location and determination of the coarse position of features (19) on the substrate (9).

Abstract: A method for repairing a multi-layered damage area in a multi-layered composite structure. The method first includes obtaining depth measurement data, and obtaining topographical measurement data by laser scanning the surface of the damage area. This depth measurement data and topographical measurement data are inputted into a microprocessor along with thickness data of each layer. All inputted information is correlated among itself to thereby internally produce a three-dimensional damage area display-replica and interpolate a two-dimensional pattern of each layer of the damage area and of the surface of the damage area. The damage area is removed by first projecting a two-dimensional laser pattern of the damage area thereat on the surface of the structure, and thereafter manually removing the area to produce a void. Repair is accomplished by projecting onto respective replacement material a two-dimensional laser image pattern of each layer and manually cutting that layer according to the appropriate pattern.

Abstract: A technique for evaluating the topography of a cornea in which a virtual object of a keratoscope pattern isured. The topography system includes a structured light source to create the keratoscope pattern or another diagnostic pattern, an optical assembly to focus the created pattern upon or behind the cornea, and for capturing the image reflected off the patient's eye and directing the reflected image toward an imaging system for processing. Light emitted by the light source is preferably not in the visible range, to minimize discomfort to the patient. Since the topography is evaluated with a projected virtual image, there is no nose or brow shadow, thereby allowing better corneal coverage. The optical system includes an aperture stop which is preferably conjugate with a point behind the corneal surface approximating the center of a normal cornea. Thus, wide angle capture is achieved as reflected rays reaching the imaging system appear as if they originated at the center of the cornea.

Abstract: Images of an object viewed from a plurality of points of view is input through an image inputting unit. Change of orientation of the image inputting means, occurring when the images of the object are input, is detected. Change of position of point of view, occurring when the images of the object are input, is detected. Characteristic points are extracted from the image which is input previously, each of the characteristic points corresponding to a respective one of objects points on the object. Corresponding points are extracted from the image which is input currently, each of the corresponding points corresponding to a respective one of the characteristic points. The three-dimensional position of each of the object points is calculated, based on the change of orientation and the change of position of point of view of the image inputting unit and the data of the characteristic points and the corresponding points.

Abstract: Apparatus for determining a best trajectory for laser CVD through a strategy of acquiring a series of two-dimensional plane images of the substrate. These images, taken together, contain topographical information as well as local reflectivity and thermal mapping information. The images are combined in digital format with additional substrate mapping information to calculate a best three-dimensional trajectory for the desired laser operation. The technique is especially suitable for compensation of tilt or severe height variation on microelectronic parts. The apparatus can deposit platinum conductors on integrated circuits by pyrolytic deposition from Pt(PF.sub.3).sub.4 vapor.

Abstract: A small-sized precision distance measuring apparatus. When a laser beam 1b reflected from an article is received on a photodetector array (30) through a lens array (20), the effective area of the photodetector array (30) is calculated on the basis of the output from the photodetectors, and the distance from the lens array (20) to the article 11 is calculated from the calculated area and the angle of view of the lenses constituting the lens array (20). If pixels (33a, 33b, 33c) of an image on a sensor array, corresponding to the coordinates of elements in the space (12), are determined on the basis of the positional relationship between the lenses (41a, 41b, 41c) of a lens array and photodetectors (51a, 51b, 51c) of the sensor array, the comparison of image information on the pixels (33a, 33b, 33c) can be made to determine the coordinate positions representing the profile of the article 11 from the coordinate positions of the space (12), thereby determining the distance to the article (11) and its shape.

Abstract: The optical touch probe has a first target at the distal end thereof on the contact element in a standard probe. The probe is mounted to a video camera of an optical coordinate measuring machine to image the target on the camera. Movement and position of the target in the X and Y coordinates is indicated by the machine's computer image processing system. A second target is mounted to the proximal end of the probe and indicates movement and position in the Z coordinate. The second target may obscure a photodetector, but preferably is parfocused on the camera by light beam parallel to the X,Y plane. Preferably there are two second targets illuminated by orthogonal beams parallel to the X,Y plane. Rotation around the Z axis then may be calculated by the computer when star probes are used. Auto changing racks are also disclosed for holding multiple probes, a probe holder, and lenses for selective mounting on the camera.

Abstract: A method is disclosed for generating a categorical depth map of a scene using passive defocus sensing. In a preferred embodiment three synchronized CCD cameras focused at different distances detect three images of the same scene. An image processor partitions the images into an array of regions and calculates a sharpness value for each region. The sharpness value for a region is calculated by summing over all pixels (x,y) in the region the absolute difference in the intensity value of a pixel (x,y)( with pixel (x-k,y-l), where k and l are constants. The image processor then constructs a depth map of the scene by determining for each region the image with the greatest sharpness in that region. An application of the invention to a mobile robot control system is described in detail. Among other applications, the method may be used for collision avoidance, object detection, and speed measurement.

Abstract: A system for measuring the quality of pavement surfaces. An amplitude modulated laser scanning system, mounted on a motor vehicle, scans the pavement surface as the motor vehicle travels over it. A detector detects the laser beam reflection from the surface and a phase measuring device counts pulses to digitally determine the phase shift in the reflected laser beam in order to calculate the profile of the surface. The profile information is used to determine various quality features of the pavement surface.

Abstract: A method of defining a sensing system for detecting the presence of an object in a volume of space under surveillance by determining the optimal placement of a plurality of energy beams which are projected into the volume which comprises the steps of (A) placing the object at a preselected position within the space; (B) directing a plurality of sample beams of energy, which have a predetermined orientation, from a source onto the object; (C) detecting the reflections of the sample beam energy from points on the object by energy detectors; (D) recording the preselected position of the object, the predetermined orientation of sample beams, and the detection status of the energy detectors; (E) changing the equatorial and azimuthal angles of each of the beams and repeating steps (B), (C) and (D); (F) moving the source of the sample beams relative to the object; (G) repeating steps (B) through (F) to produce spatial maps of the locations at which the object is positioned when each of the energy detectors detect re

Abstract: A three-dimensional measurement method and device are intended for fast and accurate measurement of large objects such as vehicles. The method includes the steps of determining approximate measurement positions of a shape measurement sensor; positioning the sensor at successive approximate measurement positions to read off the shape of surface portions of the object represented by points on the object whose co-ordinates are expressed in a system of axes fixed relative to the sensor; identifying accurate positions of the sensor at the approximate measurement positions relative to a predetermined fixed system of axes; and converting the co-ordinates of the points of the surface portions expressed in the system of axes fixed relative to the sensor into co-ordinates expressed in the fixed system of axes on the basis of the identified accurate positions of the sensor.

Abstract: A system is described for rapidly and accurately determining the topography of land masses as well as individual x,y,z coordinates of discrete targets. The system incorporates a laser altimeter, a laser scanning/steering system with sensor for receiving reflected laser beams, a global positioning system or other non-ground-based reference means, a video camera, computers, and processing software. The system, mounted to an aircraft, selectively scans or steers a pulsed laser altimeter over a swath or point on earth. A Global Positioning System (GPS) or other non-ground-based reference means records the aircraft's position, altitude, and time of position. Concurrently, a computer system records and time tags the laser's range, scanner angles, and airborne platform's roll, pitch, and heading. The processing software correlates all events and measurements using time to determine precise x,y,z coordinates of the ground/targets.

Abstract: The present invention relates to a stereo image measuring apparatus for displaying stereo images and effecting three-dimensional measurement and a correlation process on a screen for displaying the stereo images, and particularly to a stereo image measuring apparatus for making it possible to easily take hold of measuring points and to effect a correlation process after feature points have been extracted in the vicinity of the position where each cursor exists. Corresponding points for other image, which correspond to measuring points for one image, are searched. Each of display units serves so as to apply marks on the determined corresponding points based on the measured points and the result of the correlation process.

Abstract: A system for measuring the quality of pavement surfaces. An amplitude modulated laser scanning system, mounted on a motor vehicle, scans the pavement surface as the motor vehicle travels over it. A detector detects the laser beam reflection from the surface and a phase measuring device counts pulses to digitally determine the phase shift in the reflected laser beam in order to calculate the profile of the surface. The profile information is used to determine various quality features of the pavement surface.

Abstract: Circular reference features such as drilled holes are located in an area of a part such as a cylinder head, the surface of which is laser scanned to obtain scan data. The scan data provides height values of the part. Differences in height values are used to determine the points on scan lines which are boundary points of the circular holes. A first algorithm is used to estimate the contour and radius of each hole. A second algorithm provides a correction factor for the radius of each hole. The circular reference features are used for registering the part relative to a reference datum. Methods are provided that allow the accurate determination of the location of such reference features to within 0.01 mm. (0.0004 in.) from the scan data. The method may be utilized to create modified scan data to machine the part. The method may be utilized iteratively from different views of the part to obtain data which represents the part.

Abstract: A rangefinder system employs three laser rangefinders for determining three dimensional coordinates, each rangefinder using a steerable mirror for aiming the rangefinder beams at a series of retroreflectors. The beams are modulated at 1.5 GHz. The system includes a signal at an offset frequency of 1 kHz for phase detection. A digital phase detector under control of a local computer, as is the mirror, computes phase difference which is used to measure the distances to the retroreflectors. Correction is made for zero point phase drift of the circuit of each rangefinder and a benchmark reference to a distant retroreflector corrects for atmospheric effects on the measurements. A central computer directs the implementation of the tasks of the local computers of each rangefinder and computes and displays trilateration computation results made from the three rangefinders. The system can measure the distance to five different points per second with ranges up to 120 m at all accuracy of about 50 .mu.m.

Abstract: An apparatus for determining the position of a surface of a specimen relative to a reference point. The apparatus has a beam source which produces a narrow beam and a beam splitter splits the narrow beam into a primary beam and the secondary beam. The primary and secondary beams are directed by the beam splitter or by a reflector onto the surface of the specimen. The impact points of the primary and secondary beams on the surface of the specimen form images which are monitored by a photo-sensor array. A processor uses the images of the impact points to calculate the distance between the surface of the specimen and the reference point. The use of two such apparatus allows for the thickness of the specimen to be measured.

Abstract: The formation of Epipolar (or orthogonal) images from linear sections of a two-dimensional scene image in order to build up a depth map of the scene image using Hough transform techniques presently requires a spaced array of image sensors or scanning movement of a single sensor and then electronic processing of the image signals. Herein, optical radiation from a linear section of a scene image passed to deflector means, for example an elongate helical reflector, which deflects the radiation in dependence upon displacement along the section so as to form an array of side by side images of the linear scene image section as soon from different points therealong. Instead of single helical reflector, the deflector means could comprise a series of mirrors set at different angles or an array of Dove prisms which each act to rotate the linear image it receives.

Abstract: A stereoscopic computer vision system that uses a novel algorithm for obtaining the best match between corresponding features in the left and right images of desired objects in the image scene, finds the disparity between corresponding features in the left and right views and then uses the disparity to calculate the distance of the desired object from the two cameras used to provide the left and right images.

Abstract: A system and a process for identifying three-dimensional coordinates and orientation to a robot. A pair of CCD video cameras are used to measure the position of a laser or other light source spot on the surface of a workpiece. The laser and cameras need not be fixed to each other, and the laser may be handheld. In operation, the light source provides a small spot of light centered on the location to be indicated to the robot. The spot of light is then located in the field of view of each of the cameras. Using the concept of stereo triangulation, the three-dimensional coordinates of the spot are calculated by a microcomputer. These coordinates are then transformed into a form which is recognizable by the robot. The spot of light from the object can also be generated by an emitter (such as an LED or Laser diode) which is fixed on the workpiece and stimulated by an energy source.