Abstract: A three-dimensional measurement method of geometric parameters of a rope or a cable provides for obtaining a three-dimensional representation of a plurality of 3D contour points of the rope or cable and calculating the geometric parameters thereof, such as diameter, roundness and axis. A calibrated three-dimensional optical measurement system for measuring geometric parameters includes a plurality of digital image acquisition devices and a digital image processing device configured to perform the steps of the three-dimensional measurement method.

Abstract: A system and method for controlling characteristics of collected image data are disclosed. The system and method include performing pre-processing of an image using GPUs, configuring an optic based on the pre-processing, the configuring being designed to account for features of the pre-processed image, acquiring an image using the configured optic, processing the acquired image using GPUs, and determining if the processed acquired image accounts for feature of the pre-processed image, and the determination is affirmative, outputting the image, wherein if the determination is negative repeating the configuring of the optic and re-acquiring the image.

Abstract: The appearance inspection device inspects an appearance of a crimp terminal by capturing an image of the crimp terminal with a camera while applying illumination light onto the crimp terminal. The device includes an illumination unit for applying illumination light onto a crimp terminal and cameras that capture an image of the crimp terminal. A planar gradation light source having brightness that gradually changes in a predetermined direction from one side on an illumination surface toward another side is provided as the illumination unit. The cameras are disposed such that the gradation light source is reflected on an image obtained by the camera capturing the image of the crimp terminal, as a reflected image on a surface of the crimp terminal.

Abstract: A projector can be configured to project a pattern into a camera's field of view. A structural setting can be configured to receive an object in a predetermined position in the field of view. A sensor can be configured to detect that the object is in the predetermined position. A processor can be configured to, in response to the sensor detecting that the object is in the predetermined position, enable operation of the camera. The camera can be configured to obtain one or more images including the pattern on first and second surfaces of the structural setting, and the pattern on the object while the object is in the predetermined position. The processor can be configured to determine dimensions of the object based upon positional information for the first and second surface of the structural setting.

Abstract: A 3D profile measurement method includes: forming structured light having a sinusoidal intensity pattern by forcing light to pass through a grating filter and an objective lens; acquiring a structured illumination image of a measurement object by photographing the measurement object with the structured light projected thereon at predetermined intervals in a height direction of the measurement object and a uniform illumination image of the measurement object is acquired by photographing the measurement object under illumination with general light rather than the structured light; generating a Hi-Lo image by using the structured illumination image and the uniform illumination image at each height of the measurement object; extracting height-specific intensity of respective pixels in the plural Hi-Lo images; and generating a 3D profile of the measurement object based on the obtained surface position.

Abstract: A method for measuring a three-dimensional shape includes the steps of: forming a pattern on a light irradiated to an object from a light source unit installed in an electronic device by a pattern unit installed in the electronic device; generating image data by photographing the object to which the light on which the pattern is formed is irradiated by a camera unit installed in the electronic device; generating phase data for the object using the image data, and generating, using the phase data by a data generation unit, feature value data for a feature value of the object; and determining, by a determination unit, whether the feature value data is identical to pre-stored reference value data using the feature value data and the pre-stored reference value data.

Abstract: Even in a case where an amount-of-reflected-light distribution of a surface is locally different, in order to measure a distance with high accuracy, at least one embodiment of a distance measurement apparatus includes an image acquisition unit configured to acquire a first captured image obtained by capturing a measurement target object onto which a measurement pattern is projected, and a second captured image obtained by capturing the measurement target object irradiated with approximately uniform illumination, a smoothing filter determination unit configured to, based on the second captured image, determine a smoothing filter to be applied to the first captured image, a smoothing filter application unit configured to apply the smoothing filter determined by the smoothing filter determination unit to the first captured image, and a measurement unit configured to measure a distance from the measurement target object based on the first captured image to which the smoothing filter is applied.

Abstract: Disclosed are methods, circuits, optical assemblies, devices, systems and associated computer executable code for estimating for three dimensional imaging. According to some embodiments, there may be provided a projector operable to project a bi-dimensionally coded pattern to provide a first projection of the bi-dimensionally coded pattern and a second projection of the bi-dimensionally coded pattern. The first projection and the second projection may be offset or rigidly shifted with respect to one another, such that a first reflection off an object which is associated with the first projection and a second reflection off the object which is associated with the second projection are provided. A signal corresponding to the first reflection and a signal corresponding to the second reflection may be co-processed.

Abstract: An imaging system and methods for using an imaging system where the operator is able to variably adjust the parallax distance for enhanced stereo performance are disclosed. In addition, by coordinating the parallax distance with the optical settings of the camera, artificial 3D experiences can be created that give a user the perception of observing a scene from a distance different than that actually employed. The imaging system may also include a plurality of stereo camera supersets, wherein a first one or more stereo camera supersets are positioned at a different height relative to a first stereo camera superset. Novel specific uses of the camera system, such as in capturing events of interest are described. Useful techniques for extracting or encoding wide field of view images from memory are also disclosed.

Abstract: A method for detecting decalibration of a depth camera system including a first, second, and third cameras having overlapping fields of view in a direction includes: detecting a feature in a first image captured by the first camera; detecting the feature in a second image captured by the second camera; detecting the feature in a third image captured by the third camera, the third camera being non-collinear with the first and second cameras; identifying a first conjugate epipolar line in the second image in accordance with a detected location of the feature in the first image and calibration parameters; identifying a second conjugate epipolar line in the second image in accordance with a detected location of the feature in the third image and the calibration parameters; and calculating a difference between a detected location of the feature in the second image and the first and second conjugate epipolar lines.

Abstract: A sameness judgment unit of an object recognition apparatus sets a threshold value for a relative distance between the first object and the second object, for judging whether or not the first object and the second object are the same. If at least a portion of the first object exists on a travel path of a vehicle, and the second object exists outside of the travel path, the sameness judgment unit judges that the first object and the second object are different objects, even if the relative distance is less than or equal to the threshold value.

Abstract: A virtual user interface in a 3D environment is projected onto a display object, such as an open hand. An operating object, such as a stylus or a second hand with an index finger extended, may be used to select input features of the projected user interface. In one scenario, for example, a telephone keypad may be projected onto the open hand and the index finger may be used to select a particular number on the keypad. Images of the hands may be segmented to produce contours of the finger and open hand, and these contours are used to determine the location of the finger relative to the open hand.

Abstract: An imaging system and methods for using an imaging system where the operator is able to variably adjust the parallax distance for enhanced stereo performance are disclosed. In addition, by coordinating the parallax distance with the optical settings of the camera, artificial 3D experiences can be created that give a user the perception of observing a scene from a distance different than that actually employed. The imaging system may also include a plurality of stereo camera supersets, wherein a first one or more stereo camera supersets are positioned at a different height relative to a first stereo camera superset. Novel specific uses of the camera system, such as in capturing events of interest are described. Useful techniques for extracting or encoding wide field of view images from memory are also disclosed.

Abstract: According to an embodiment, a measuring device includes a projector, an image capturing unit, and a first calculator. The projector projects, onto a target, a first superimposed pattern which is obtained by superimposing a first pattern having a periodic change and a second pattern configured with a first design for specifying a period of the first pattern. The image capturing unit captures the target, onto which the first superimposed pattern is projected to obtain an image. The first calculator performs matching of the first design taken by the image capturing unit, which is included in the first superimposed pattern in the image, with the first design projected by the projecting unit, and calculates correspondence between a second superimposed pattern, which points to the first superimposed pattern captured in the image, and the first superimposed pattern.

Abstract: An imaging system and methods for using an imaging system where the operator is able to variably adjust the parallax distance for enhanced stereo performance are disclosed. In addition, by coordinating the parallax distance with the optical settings of the camera, artificial 3D experiences can be created that give a user the perception of observing a scene from a distance different than that actually employed. The imaging system may also include a plurality of stereo camera supersets, wherein a first one or more stereo camera supersets are positioned at a different height relative to a first stereo camera superset. Novel specific uses of the camera system, such as in capturing events of interest are described. Useful techniques for extracting or encoding wide field of view images from memory are also disclosed.

Abstract: A stereoscopic optical system includes: two objective optical systems arrayed parallel to each other with a space therebetween; two parallelogram prisms that bring optical images close to each other by respectively deflecting lights collected by the objective optical systems twice; an image pickup element arranged at image formation positions of the light fluxes collected by the objective optical systems to take the two optical images brought close to each other by the prisms; and a diaphragm member that blocks a portion of the light flux on at least one of an inner side and an outer side in a direction of the space at any position apart from a pupil position of each of the objective optical systems in a direction of an optical axis, wherein the diaphragm member is arranged on the inner side in the direction of the space, and satisfies a conditional expression L0?Ihy?W>Z0×sin ?.

Abstract: When generating an origin signal of an encoder having a scale on which an incremental pattern and the origin pattern are formed, an origin signal having a necessary position and width is generated by software based on an origin waveform obtained from the origin pattern. This enables origin detection with excellent repeatability, S/N ratio (pulse width), and bidirectionality while maintaining ease of mounting and adjustment.

Abstract: An apparatus for inspecting a printed circuit board device, the device including at least one component mounted on a circuit board, the apparatus comprising an object carrier for carrying the printed circuit board device, imaging means for imaging along an optical axis so as to receive light reflected from surfaces of the device when placed on the object carrier within a field of view of the imaging means, and light projecting means for projecting light toward the object carrier in an oblique direction with respect to the optical axis of the imaging means for illumination of said surfaces of the device. The light projecting means includes a substantially dome-shaped structure incorporating a plurality of light elements for producing and projecting the light. Said plurality of light elements includes light elements of different light characteristics and light elements of different orientations of projection for creating a predetermined illumination pattern on said surfaces of said printed circuit board device.

Abstract: A control unit box and one of standard point members are provided close to a connection of first and second bars. A standard plane is defined by the standard point members. A loop antenna is provided in a mount unit situated on the top surface of the control unit box. The box is positioned such that a ratio of a second distance to a first distance is less than tan 8°. The first distance is from the point member to the mount unit, along the standard plane, and the second distance is from the standard plane to the top surface of the mount unit, along a direction perpendicular to the standard plane. The antenna is connected to an oscillator of 310 MHz. With respect to the antenna, the total length is approximately 0.48 m, a height from the top surface of the unit box is approximately 9.5 mm, and the inner diameter is approximately 25 mm.

Abstract: The invention is a three dimensional sensing system which utilizes two flexibly located cameras for receiving and recording visual information with respect to a sensed object illuminated by a series of light planes. Each pixel of each image is converted to a digital word and the words are grouped into stripes, each stripe comprising contiguous pixels. One pixel of each stripe in one image is selected and an epi-polar line of that point is drawn in the other image. The three dimensional coordinate of each selected point is determined by determining the point on said epi-polar line which also lies on a stripe in the second image and which is closest to a known light plane.

Abstract: An automatic map complication system, for deriving information from a pair of stereoscopic photographs by scanning portions thereof which represent homologous imagery comprising:first means for scanning at least portions of a pair of stereoscopic photographs and developing video signals in accordance therewith;second means, including computing means, operable in a sequence of cycles of operation, for estimating for successive cycles of operation, on the basis of at least photogrammetric data related to said pair of photographs, the portions of said photographs which represent homologous imagery and controlling said first means to synchronously scan said portions; andthird means responsive to said video signals for comparing said video signals therein and producing error signals which represent the degree of error in said second means in estimating said portions of said photographs as representing homologous imagery, said second means including means responsive to said error signals for updating the estimate o

Abstract: A system for producing 3-D stereoscopic graphic hard copy output from computers is described. The left and right stereo images from the computer are spatially modulated, spatially multiplexed and then printed on a special paper. This special paper consists of a micropolarized sheet laminated to a polarization preserving reflective sheet. The spatially multiplexed stereo pair when printed on the micopolarizer and viewed with appropriatley polarized glasses, 3-D stereo images will result with full depth perception realized. The micropolarizer sheet seves as a spatial demultiplexer to separates the left and right images and codes them by means of two polarization states. The polarized spectacles serve as decoders and present to the left eye the left image and to the right eye the right image.

Abstract: The invention is directed to a method and an apparatus for scanning the terrain surface and other objects transversely to the flight direction or direction of motion of the scanner with a detector row arranged perpendicularly to the direction of scanning and containing several individual detectors of equal size, wherein the terrain- or object strip to be scanned is divided into various distance ranges, within which the fundamental detector signals within the detector row as well as of consecutive exposure periods are collated respectively in such a way by averaging, that the collated individual signals form or cover respectively one object pixel of approximately constant magnitude independent of the scanning distance, and wherein these object pixels stand always at right angles with respect to the scanning beam and where each scanning sweep produces a terrain- or object strip with approximately equal object pixel size as well as constant object pixel number along the width and length of the scanned strip.

Abstract: A three-dimensional shape of an object is recognized by developing enveloping surfaces of the object by a cone-silhouetting method, wherein the object is picked up by a binocular three-dimensional vision method by making use of geometrical restraint conditions derived by the cone-silhouetting method. The binocular parallax is increased to thereby ensure the recognition of the three-dimensional shape with improved accuracy. Local concave portions which can not be recognized by the cone-silhouetting method by itself are recognized with higher accuracy.

Abstract: A stereoscopic photographic measuring device which can execute an analysis of a stereoscopic photograph very efficiently. The stereoscopic photographic measuring device comprises a table for receiving a set of stereoscopic photographs thereon, and an optical system body constructed for movement in two-dimensional directions relative to the table. The table has a plane coordinate reading means provided thereon for reading coordinates of the stereoscopic photographs while the optical system body has provided thereon a stereoscope unit for observing the stereoscopic photographs in a stereoscopic vision, first and second cursors disposed within a range wherein the first and second cursors can be observed by way of the stereoscope unit, and a distance adjusting means for adjusting a distance between the first and second cursors.

Abstract: A method of forming a three-dimensional stereo vision is disclosed in which, in order to prevent the erroneous detection of an object point in the conventional method using two image focusing lens systems, three image points of an object point formed by logically and/or physically selecting three image focusing lens systems and three image sensing surfaces from a multiplicity of image points on an image sensing surface by using the fact that a positional relation among three image points of the same object point is similar to the positional relation among the three image focusing lens systems, and the positional information of three selected image points on the image sensing surface is used for obtaining three-dimensional distance information of the object point.

Abstract: Method of determining stereoscopic geometry of an object through photometric stereoscopic measurement with high accuracy. Three or more images of the object picked up in a same fixed direction by varying the state of light sources are derived. Relationships among the images are corrected so that an evaluation function determined by making use of redundancy of the images assumes a minimum value, to thereby prepare a reflectance map to be used in determining orientations of surface elements of the object. Through integration of the orientations, the surface shape of the object is determined. The method is applicable to the image processing in a scanning electron microscope.

Abstract: A cartographic apparatus for determination of the elevations of features and heights of objects from stereoscopic images of complementing input records includes a parallax bar and movable reticles for generating a floating mark over points of interest in the records. The apparatus also includes a microprocessor to compute compensation factors based on values determined during initial set up and means responsive to those factors to compensate automatically for y parallax and for errors in x parallax difference as the floating mark is moved and to compute automatically object heights and feature elevations.

Abstract: A stereophotogrammetric surveying and evaluation method is presented. A camera is carried over the terrain of interest, the camera having three sensor lines arranged transversely or obliquely to the line of flight. From the resulting three overlapping line image strips both elevational terrain data and camera orientation data are statistically obtained.

Abstract: A system for recognizing a three-dimensional object includes a plurality of image pickup apparatus, e.g. TV cameras, by which images of the object are picked up from at least three directions. Feature points are extracted from each of at least three images obtained. Two sets of feature points on epipolarly lines are formed which lines are formed on at least two of the images by a feature point on another image. A set of feature points is selected which satisfy a restricting condition determined by the relationship of the image picking-up direction.

Abstract: Methods are provided for reducing the number of projected patterns required to make two- or three-dimensional surface measurements on a sub-class of surfaces comprising relatively smooth surfaces. By including apriori knowledge about the surface to be measured, pattern ambiguities can be resolved by processing rather than by additional projected patterns.

Abstract: Methods are provided for reducing the number of projected patterns required to make two- or three-dimensional surface measurements on a sub-class of surfaces comprising relatively smooth surfaces. By including apriori knowledge about the surface to be measured, pattern ambiguities can be resolved by processing rather than by additional projected patterns.

Abstract: Methods are provided for reducing the number of projected patterns required to make two- or three-dimensional surface measurements on a sub-class of surfaces comprising relatively smooth surfaces. By including apriori knowledge about the surface to be measured, pattern ambiguities can be resolved by processing rather than by additional projected patterns.

Abstract: Disclosed herein is a binocular artificial vision system including left and right hand video cameras providing left and right video signals to a stereo correlator providing a correlated distance signal at the output thereof. The left and right hand video cameras have overlapping fields-of-view, the stereo correlator derives a quality of correlation signal as well as a range distance signal from the left and right video signals, and means are provided to vary the effective eyebase of the video cameras in response to the quality of correlation signal.

Abstract: A range-finding system comprising the hardwired video processing of two side-by-side TV stereo images of a scene to provide automatic, rapid, quantitative ranging to noncooperative objects. A single TV camera with appropriate optics to provide stereo inputs or, in a preferred embodiment, two TV cameras, provide the stereo images. Range is determined for any change of contrast in the common TV stereo scene to obtain the parallax displacement of corresponding object features with a three scan line delay of less than 200 microseconds. The video of the synchronized line scan of both cameras is stored as they are scanned, thus range can be determined with relative motion between the stereo camera and objects in the scene. Range is stored in on-board RAM's for each pixel of the TV scene and is available after three TV lines of delay. Range up-dating is continuous as the TV raster is scanned, or the range of a particular TV frame may be frozen for detailed study.

Abstract: A photogrammetric stereoplotter using a stereoscopic binocular unit (1) to provide an image of spatially separated masters (4,5) and including a cursor (6) providing X Y coordinates and measuring marks providing Z coordinates in which the X Y Z coordinates are fed through a stereogrammetric unit (7) to a computer (8) with a display and/or printer (12,13) and an interface (14) to a display tube (16) and through an optic train (18) to at least one side of the binocular unit (1), and including a topographic keyboard unit (10) arranged to feed information to record the trace, and optionally a voice recognition unit (20) with two-way communication between operator and computer (8), and means in the computer (8) whereby model coordinates from the said binocular unit (1) are changed to image coordinates by the computer (8) to achieve precise superimposition of the trace image to eliminate visual disturbance.

Abstract: A method for locating points on a surface in which the surface is irradiated selectively with an irradiating volume which has a varying intensity that defines a first pattern. After irradiating the surface with the first pattern, the surface is irradiated similarly with volumes having varying intensities defining a second or more patterns. Both of these patterns are applied to a point to be located on the surface. The radiation impinging on the surface is recorded by a camera which forms images of the patterns. The images are scanned to find the intensities of the point in the two or more patterns. More than one pattern may be simultaneously irradiated, using different frequencies to distinquish the data. The location of the point on the surface is dependent on a predetermined ratio or difference of the intensities of the point in the two or more patterns.

Abstract: A method for locating points on a surface, in which the surface is irradiated selectively with an irradiating volume which has a varying intensity that defines a first pattern. After irradiating the surface with the first pattern, the surface is irradiated similarly with volume(s) having varying intensity(ies) defining a second (or more) pattern(s). Both (or all) of these patterns are applied to a point to be located on the surface. The radiation impinging on the surface is recorded by a camera which forms images of these patterns. The images are scanned to find the intensities of the point in the two (or more) patterns. The location of the point on the surface is dependent on a predetermined ratio or difference of the intensities of the point in the two (or more) patterns. The patterns may be linear, sinusoidal, smooth, non-smooth and/or two dimensional functions ultimately producing a single valued ratio or difference result.

Abstract: An apparatus for automatically adjusting the level of at least one surface point on a flexible platen of a photogrammetry apparatus having photogrammetric images projected thereon in first and second colors is disclosed as comprising means for receiving and transmitting the first and second colored images at the surface point, which is attached to and movable with the receiving and transmitting means and means for vertically positioning the receiving and transmitting means. There is also provided means for converting the transmitted colored images into electrical signals, which are proportional in strength to the intensity of the colored images, and means for controlling the positioning means in response to the electrical signals, whereby the surface point is adjusted to a position where the colored images intersect.

Abstract: A method and apparatus for determining spatial information regarding the points on an object situated in an object space wherein substantially planar laterally spaced diverging radiant energy beams are applied to the object space and a recording means records the reflected radiant energy in such space from a position whereat the radiant energy from points in the space and along the radiant energy beams is uniquely defined.

Abstract: A plurality of projectors are positioned in spaced relationship about an object with a surface to be geometrically analyzed. The projectors have cooperating masks which project onto the object illuminated patterns that subdivide the object into predetermined sections. Each mask has a predetermined pattern of sections, and is applied in sequence. The masks are cooperatively advanced in the projectors, with a separate illuminating pattern prevailing on the object each time that the masks are advanced. The combinations of the patterns on the masks define closely-spaced sections subdividing the object. The patterns are coded so that each section is uniquely defined in coded form. Cameras having the entire object within their field of view, photograph the object each time a separate mask is applied. To sense sections of the surface independent of the reflectance characteristics of the surface, the projectors direct two separate illuminating signals at the object surface.

Abstract: The method of generating data for files containing information regarding three-dimensional surface configurations, involving selective compilation of area data through use of projected rays of differing orientation, recording of the radiation patterns produced by these rays on the surface, and correlation of records from overlapping fields of view to meld information from contiguous areas into a continuous data bank.

Abstract: The invention concerns an electronic correlator for the evaluation of stereo-couples of photographs. Said electronic correlator comprises a normal correlator into which non-delayed signals are fed which in turn are derived from homologous points of each of the photographs of said stereo-couples. It further comprises an auto-correlator into which the image signals are fed non-delayed from the one photograph and delayed from the other photograph. A subtraction unit is connected to the normal correlator and to the auto-correlator. Furthermore two orthogonal correlators are provided into which the delayed and non-delayed image signals derived from the two photographs are fed crosswise delayed and non-delayed. The two orthogonal correlators are followed by a subtraction unit. By virtue of such an arrangement the trend inherent in the image signal functions to be correlated are taken into consideration and thus the quality of the image correlation is increased.

Abstract: The surface to be sensed or scanned is placed in the path of a projector which is moved along an axis of the surface. The path of motion of the projector is subdivided into predetermined sections which are illuminated by the projector in accordance with a predetermined sequential pattern. This procedure of moving the projector is repeated a predetermined number of times, with a separate illuminating pattern prevailing each time that the projector is moved relative to the surface and traverses the entire surface to be scanned. The combinations of the patterns obtained from the repeated scannings of the projector define closely-spaced sections of the surface. The patterns are coded so that each section is uniquely defined in coded form. A camera having the entire surface within its field of view photographs the surface each time that the projector is moved along the axis of the surface.

Abstract: A plurality of projectors are positioned in spaced relationship about an object with a surface to be geometrically analyzed. The projectors have cooperating masks which project onto the object illuminated patterns that subdivide the object into predetermined sections. Each mask has a predetermined pattern of sections, and is applied in sequence. The masks are cooperatively advanced in the projectors, with a separate illuminating pattern prevailing on the object each time that the masks are advanced. The combinations of the patterns on the masks define closely-spaced sections subdividing the object. The patterns are coded so that each section is uniquely defined in coded form. Cameras having the entire object within their field of view, photograph the object each time a separate mask is applied.

Abstract: A device for photogrammetric evaluation of stereo-couples of photographs which are scanned light electrically and, in order to obtain height coordinate values, are evaluated by correlation.The device is particularly useful in the evaluation of aerial photographs. To reduce correlation errors due to interfering signals obtained from different correlator signal channels and, hence, to increase the precision of a correlation operation, at one time only the informations from one correlator signal channel in each of the two scanning channels are exploited to obtain the informations from the scanned stereo-pair of photographs.Therefore, it is desireable that, in the course of the correlation operation, the highly resolving correlator signal channels are predominantly and for a considerable long time employed to correlate the informations. According to the invention gate circuits are inserted between the correlator signal channels and the discriminator.

Abstract: The spatial locations of points defining a specular surface are determined by disposing the specular surface in the field of view of a lens and by using the specular surface to view by reflection an irradiated reference surface disposed successively in different positions. Reference surface indicia viewed in common line of sight relation to each specular surface point in such different positions of the reference surface are identified. Radiant energy reflected by a specular surface point through the lens node and the location of the lens node defines a further line in space. The intersection of this further line and such line of sight defines the spatial location of such specular surface point. Photographic records made with the reference surface in such different positions contain representations of reflected radiant energy for all specular surface points in the field of view of the lens and in line of sight relation to the reference surface.

Abstract: An automatic stereo plotter comprises a correlator and a follow-up unit, which is preferably employed to follow-up a measuring mark in z-direction relative to a stereo model to be evaluated. In order to improve the efficiency of the stereo plotter additional means are provided which increase the amplification factor between the parallax error signals at the output of the image correlator and the follow-up signals. Thus variations in the video signals derived from the measuring photographs are compensated for. Such means are, for example, an adjustable amplifier, which can be set to a plurality of stable amplification factors, and an analog multiplier which, due to a corresponding control voltage, permits a continuous variation of the amplification.

Abstract: Apparatus to automatically analyze stereoscopic images comprising the determination of the maximum degree of correlation between two similar images of the same object projected by two objectives, for instance in a rangefinder, wherein the two images are superimposed on one or two spatial frequency filters identical in their structures, and wherein the particular generated superimposition signal, is preferably applied to a particular photoelectric detector and wherein the output signals from the latter are used for display and/or control purposes. The apparatus is improved by a system (20,20',21,21',22-25; 30-34) for generating a reference beam indicating mechanical changes affecting the image position of at least one of the measuring beams, at least one photoelectric detector (28,29;40) being associated with the one reference beam, the output signals from the one detector corresponding to the mechanical changes being used to display and/or correct the changes or the effects of same.

Abstract: For automatic focusing of a stereoscopic microscope a focusing beam of rays, preferably in the infrared range of wave length, is generated by a pulse light source, and focused on the object to be observed in the form of a small luminous area which is superimposed on the observation rays. The rays reflected back by the object along the divided paths of the observation rays are deflected from those paths and directed to impinge on separate photoelectric detectors which convert axial shifts of the object plane with respect to the microscope into a directionally dependent electric signal which controls a focusing motor to move the microscope to compensate for such shifts. A switch is provided to permit manual adjustment of focus preparatory to automatic adjustment.