Abstract: Acquisition device for taking a digital relief image of the surface of a tire having two color cameras for the acquisition of stereoscopic images. Each camera has N primary image sensors in a given primary color (R, G, B), where N is equal to or greater than two. Each camera is placed so as to acquire the light emitted (E) towards a predetermined area (Z) of the surface of the tire by N lights and reflected (F) by the surface of the tire. The N lights simultaneously project each independently and along the same direction onto the predetermined area of the surface of the tire. The projected light has a wavelength that corresponds to one of the primary colors of the cameras, according to a fringe system (S1, S2, . . . SN) consisting of an alternation of illuminated and non-illuminated bands of given width (L1, L2, . . . LN).

Abstract: A method serves the detection of surface defects of a component. The surface of the component (5) is radiated from the side with light from a light source (4, 4?). The light radiated back from the surface of the component (5) is detected by a sensor. To improve such a method, only a rear region (19, 19?) of the surface of the component (5) is radiated with light from the light source (4, 4?) and/or only the light radiated back from a rear region (19, 19?) of the surface of the component (5) is detected by the sensor and/or evaluated by an evaluation device FIG. 3).

Abstract: There is provided a displacement measurement apparatus including: a light source; a pair of diffraction gratings that light emitted from the light source enters, the pair of diffraction gratings opposing each other while being relatively movable along an optical axis; a first optical sensor that detects interference light obtained by diffracted light emitted from a diffraction grating device of each of the pair of diffraction gratings; a second optical sensor that detects non-interference light emitted from the pair of diffraction gratings; and a correction unit that corrects a signal obtained by the first optical sensor based on a signal obtained by the second optical sensor.

Abstract: A method for determining a centerline for a triangulation-based optical profilometry system, compensating for the spatial variations of the reflectance of an object's surface. The method comprises providing a luminous line on the object, the luminous line being a triangulation line superposed with a compensation line; capturing an image of the triangulation line and of the compensation line; for each position along the imaged triangulation line, determining a transverse triangulation profile from the imaged triangulation line and a transverse compensation profile from the imaged compensation line; determining a transverse correction profile given by the reciprocal of the transverse compensation profile; multiplying the transverse triangulation profile with the transverse correction profile to obtain a corrected transverse triangulation profile; computing a center of the corrected transverse triangulation profile. The centers determined at positions along the triangulation line form the centerline.

Abstract: A method and apparatus for optimizing high-speed optical inspection of parts using intelligent image analysis to determine optimal focus using high numerical aperture (NA) optics, achieve a superior signal-to-noise ratio, resolution, and inspection speed performance with very limited depth of field lenses.

Abstract: A method and an inspection system that exhibiting speckle reduction characteristics includes a light source arranged to generate input light pulses, and diffuser-free speckle reduction optics that include a beam splitter, for splitting an input light pulse from the light source into multiple light pulses that are oriented at angles in relation to each other when exiting the beam splitter, and at least one optical element for directing the multiple light pulses to impinge on an inspected object at different angles.

Abstract: The invention provides a positioning device for locating a planar light beam emitted by an optical triangulation sensor across a diameter of a hole formed in a surface of an object. The positioning device has an adjustable guiding element which is capable of locating an optical triangulation sensor at the same distance away from holes have a range of diameters. The guiding element is movably mounted relative to a platform that is fixed to the optical triangulation sensor. The guiding element comprises a body which is insertable into the hole, the body having a pair of contact surfaces for contacting diametrically opposed portions of the hole, the pair of contact surfaces being opposed to each other in a direction orthogonal to the plane of the planar light beam.

Abstract: Considerable damage to rails, wheels, and trucks can result from geometric anomalies in the wheelsets, rails, and truck hardware. A solution for identifying and quantifying geometric anomalies known to influence the service life of the rolling stock or the ride comfort for the case of passenger service is described. The solution comprises an optical system, which can be configured to accurately perform measurements at mainline speeds (e.g., greater than 100 mph). The optical system includes laser line projectors and imaging cameras and can utilize structured light triangulation.

Abstract: A system for simultaneous real-time three-dimensional geometry and color texture acquisition. The system includes a system processor for generating at least three phase shifted black and white fringe patterns with a phase shift of 2 ?/3, a light projector adapted to project the fringe patterns onto an object, the projector being electrically connected with the system processor, and a color camera for capturing the fringe patterns to generate at least three raw fringe images. The fringe images are used to calculate a black and white texture image which is further converted to a color image by employing a demosaicing algorithm. The fringe images are also used to calculate a wrapped phase map that is further processed to generate a continuous unwrapped phase map by employing a phase unwrapping algorithm and the unwrapped phase map is converted to co-ordinates using calibrated system parameters for point-by-point three-dimensional shape measurement.

Abstract: An apparatus for measurement of a three-dimensional (3D) shape includes a lens unit transmitting slit beams to a plurality of measurement objects, a light source unit irradiating the plurality of slit beams to the lens unit at different angles, an imaging unit obtaining images of the plurality of measurement objects formed by the slit beams irradiated on the plurality of measurement objects, and a calculation processing unit generating information regarding a 3D shape of the plurality of measurement objects from the images obtained by the imaging unit.

Abstract: Provided is an optical surface profilometer. The optical surface profilometer includes a Fabry-Perot resonator into which liquid crystals are inserted, a light source which supplies coherent light to the Fabry-Perot resonator, and a convex lens which is disposed in an interference pattern emitting plane of the Fabry-Perot resonator, wherein the coherent light supplied from the light source is incident to the Fabry-Perot resonator, wherein, when the light is incident, the Fabry-Perot resonator emits an interference pattern generated in a resonance mode, and wherein the interference pattern is configured so that a number of circular fringes having the same center are disposed non-linearly. As a voltage is applied to the liquid crystal layer of the Fabry-Perot resonator, an effective refractive index is changed, so that a resonance mode condition of the Fabry-Perot resonator is changed. As a result, a diameter of the interference pattern is also changed.

Abstract: Dimensions of a surface feature are determined by capturing an image of the surface feature and determining a scale associated with the image. Structured light may be projected onto the surface, such that the position of structured light in the captured image allows determination of scale. A non-planar surface may be unwrapped. The surface may alternatively be projected into a plane to correct for the scene being tilted with respect to the camera axis. A border of the surface feature may be input manually by a user. An apparatus and system for implementing the method are also disclosed.

Abstract: A three dimensional shape measurement apparatus includes an illumination section and a grating transfer unit. The illumination section includes a light source unit generating a light and a grating unit changing the light generated by the light source unit into a grating pattern light having a grating pattern. The illumination section illuminates the grating pattern light onto a measurement target in a predetermined direction. The grating transfer unit transfers the grating unit in a predetermined inclination direction with respect to an extension direction of the grating pattern and an arrangement direction of the grating pattern. Thus, manufacturing cost may be reduced, and the three dimensional shape measurement apparatus may be easily managed.

Abstract: A method of decoding hierarchically orthogonal structured light and a 3-D depth measurement system using the same include a step of detecting boundary lines encoded at an identical position between layers and a boundary line inheritance step of converting the detected boundary lines into identical boundary lines. The present invention relates to a method of precisely searching for the boundary line of a pattern of radiated structured light based on the real coordinate system of an image plane, and an object thereof is to search for a boundary line irrespective of the reflection of a surface of an object, clearly classify a true boundary line and a false boundary line in a poor radiance environment, and increase the accuracy of a boundary line placed in another layer through inheritance.

Abstract: An observing apparatus includes a lighting device for irradiating a surface of a measuring target with light having a first light source distribution, and an imaging section for imaging the surface of the measuring target. Considering a first plane passing through a measurement point, the first light source distribution is set such that: (1) a radiance L11(?) changes in a continuous or stepwise manner according to an angle ?, and (2) the radiance L11(?) is not zero in a local region of a predetermined range of ±? having a point located at a predetermined angle ?c as a center on the first plane when viewed from the measurement point, and the following equation substantially holds for arbitrary a satisfying 0<a??; L11(?c?a)+L11(?c+a)=2×L11(?c).

Abstract: A 3D shape measurement apparatus for measuring a 3D shape of an object existing on a measurement area, comprising, a pattern projection unit for projecting a pattern having a periodicity onto the measurement area, and a capturing unit for capturing an image of the area where the pattern is projected, wherein the measurement area is specified by a reference plane, a projection area of the pattern projection unit, and a capturing area of the capturing unit, and the pattern projection unit projects the pattern to be focused on the reference plane. The apparatus further comprises a first calculation unit for calculating phase information of a pattern of the captured image, a second calculation unit for calculating defocus amounts of the pattern in the captured image, and a third calculation unit for calculating a 3D shape of the object based on the phase information and the defocus amounts.

Abstract: System and method for tridimensional cartography of a structural surface. Two wires are extended in front and along the structural surface so as to define a reference surface. A measuring unit comprising a laser arrangement and a camera is moved in front of the structural surface so as to progressively scan the surface. Tow distinct light planes directed toward the structural surface are projected by means of the laser arrangement. Images of the structural surface containing lines resulting from an intersection of the light planes with the structural surface and four reference points resulting from an intersection of the light planes with the wires are captured by means of the camera. The images are processed to determine the 3D coordinates of the lines defining the mapping in a reference system bound to the reference surface considering the position and the orientation of the measuring unit based on the reference points.

Abstract: A process for determining the position of closed holes in a component is provided. By carrying out laser triangulation measurements on an uncoated component and a coated component with holes, the exact position of the holes to be reopened may be detected following the coating. A device used to carry out this process is also provided.

Abstract: Provided is a structural light based three-dimensional depth imaging method and system using signal separation coding and error correction thereof capable of detecting, removing and correcting corresponding errors between a projection apparatus and an image photographing apparatus caused by phenomena such as reflection on an object surface, blurring by a focus, and so on, using geometrical constraints between the projection apparatus and the image photographing apparatus. Here, the projection apparatus projects light, and the image photographing apparatus obtains the light. The depth imaging method includes projecting light from a projection apparatus, obtaining the light using an image photographing apparatus, and measuring a distance or a three-dimensional depth image. Therefore, it is possible to provide a structural light based three-dimensional depth imaging method and system using geometrical conditions capable of precisely obtaining three-dimensional depth information of target environment.

Abstract: A method for obtaining an incident angle ?i is provided. The method is used in a panel having at least one icon, wherein the at least one icon has a plurality of protrusions, and a light-emitting source is disposed under the at least one icon. The method includes steps of obtaining a distance W between two centers of two bottoms of two trenches formed at two sides of one of the plurality of protrusions; obtaining a half of the distance W; obtaining a vertical distance H between the light-emitting source and a center of the distance W; and performing an inverse trigonometric function operation for the half of the distance W over the vertical distance H so as to obtain the incident angle ?i.

Abstract: A method is disclosed for detecting defects in an optical component to be tested, such as a lens comprising the steps of: providing a structured pattern, recording the reflected or transmitted image of the pattern on the optical component to be tested, phase shifting the pattern and recording again similarly the reflected or transmitted image, calculating the local phase and amplitude images of the optical component to be tested, calculating a model image of a defect free optical component and determining corresponding phase and amplitude images of the defect free model optical component, comparing phase and amplitude images of both optical component to be tested and defect free model optical component, determining suspect zones in the optical component to be tested, and applying a metrics to separate dust and noise from other defects.

Abstract: An optical, such as a laser, triangulation sensor is disclosed in which a configuration of an output light beam is controlled using a mask in front of a light source. The configuration may include a plurality of coplanar spatially separated planar light beams. The mask may be movable to provide different light beam configurations. Masking parts of the light beam enables unwanted features on the measurement surface to be omitted. Also disclosed is a guide element for an optical sensor for facilitating hole diameter measurement. The guide element has contact surfaces lying on a virtual conical surface which abut the hole edge to enable consistent placement of the light beam with respect to the hole centre. Also disclosed is a guide element for an optical sensor having an aperture for framing surface features, such as a rivert to permit accurate location of the light beam therewith.

Abstract: A scanning apparatus includes a scanning head that scans an image of a document positioned on a stage glass, but varying in its distance therefrom. A boundary line is detected to determine an amount of skew therein. A skew line is compared with an established reference line, and a correction factor is calculated based on the result of the comparison. The original image processed to map the boundary line to the reference line and image data inside of the boundary line is similarly mapped based on the calculated correction factor. Beneficially, skews of an image produced when a thick book is scanned can be corrected simply.

Abstract: The invention relates to a device for the contactless detection of a three-dimensional contour, comprising a projector with an imaging element and a projection lens for depicting a stripe pattern that is generated on the imaging element in an object space. The invention further comprises a camera arrangement for the surveillance of the object space from two different directions, having two camera lenses. The projector and the camera arrangement are housed together in a measurement head that can be handheld. The invention further relates to a method for detecting a three-dimensional contour using said device.

Abstract: A pattern measurement method includes: acquiring sectional shapes of a first pattern corresponding to process parameters, respectively; using the acquired sectional shapes to calculate predicted spectral waveforms which would be obtained when light is applied to the first pattern, and adding information on the corresponding process parameters to the calculated predicted spectral waveforms, respectively, to form a waveform library; setting a process parameter to obtain a desired shape, and acquiring an actual spectral waveform of a second pattern actually created from the first pattern using the set process parameter; performing waveform matching between the actual spectral waveform and the predicted spectral waveforms to acquire matching scores for respective waveform matching, and calculating an optimum process parameter providing the maximum matching score; generating an optimum pattern sectional shape corresponding to the optimum process parameter to measure the optimum pattern sectional shape.

Abstract: A sensor system and method for analyzing a feature in a sensing volume. The system imaging the feature with a first sensor and a second sensor that cooperate to form a contiguous sensing volume.

Abstract: An interface that allows a user to explore complex three dimensional datasets. The user manipulates a physical modeling material that defines the geometry of a surface that intersects a voxel dataset and the intersected voxel values are projected back onto the surface of the physical material as image data. A position sensor captures position data specifying the geometry of the surface, a processor compares the array of data values with the captured position data to identify selected ones of these data values whose position in the array corresponds to the geometry of the surface, and a projector for illuminates the surface with an image representative of the data at the array/surface intersection.

Abstract: An optical system including a signal processing unit has been developed to study the contours of objects and/or their deformations. The optical system utilizes projectors comprising an illumination source including those outside the visible range and an observation source such as a digital camera. The optical system provides information regarding the object in such a way that renders a complete description of the surface geometry and/or its deformation. The optical system further facilitates a substantial simplification in obtaining the desired result in the form of eliminating the need for point-wise solution of simultaneous equations. The signal processing unit comprises software that, among others, provides a transformation that mimics projection and observation from infinity. The signal processing unit further reduces data processing by recognizing known geometric shapes, and automatically correcting for discontinuities of the object and/or optical system.

Abstract: A method and an apparatus for noninvasively and quantitatively determining spatially resolved absorption and reduced scattering coefficients over a wide field-of-view of a food object, including fruit or produce, uses spatial-frequency-domain imaging (SFDI). A single modulated imaging platform is employed. It includes a broadband light source, a digital micromirror optically coupled to the light source to control a modulated light pattern directed onto the food object at a plurality of selected spatial frequencies, a multispectral camera for taking a spectral image of a reflected modulated light pattern from the food object, a spectrally variable filter optically coupled between the food object and the multispectral camera to select a discrete number of wavelengths for image capture, and a computer coupled to the digital micromirror, camera and variable filter to enable acquisition of the reflected modulated light pattern at the selected spatial frequencies.

Abstract: The present invention relates to printable security paper that includes a region capable of receiving printed indicia on the front side and on the reverse side which are observable in reflected light and form an image observable in transmitted light, as security element protecting against two-sided copying, characterized in that such region is a screened region having an average overall opacity less than the opacity of the vellum part of the rest of the paper, said screened region being made up from alternations of vellum miniregions, having an approximately constant thickness equal to that of the vellum part of the rest of the paper, and of miniregions of reduced opacity because of their smaller thickness compared with the vellum miniregions. The invention also relates to the security document obtained with this paper.

Abstract: The invention is directed to a method for illuminating an object and projecting its image on a ground glass screen. Optical comparators conventionally use incandescent illumination, either mercury arc or halogen. The use of an array of high intensity LED devices, provides many options for packaging the required optical components used in comparators.

Abstract: The invention concerns a security document comprising, as security element against recto/verso copying, indicia present on both sides and capable of being viewed under reflected lighting and forming an image capable of being viewed under transmitted light. The invention is characterized in that said indicia comprise lines and form said image with 3D effect.

Abstract: A three dimensional shape measurement apparatus includes an illumination section and a grating transfer unit. The illumination section includes a light source unit generating a light and a grating unit changing the light generated by the light source unit into a grating pattern light having a grating pattern. The illumination section illuminates the grating pattern light onto a measurement target in a predetermined direction. The grating transfer unit transfers the grating unit in a predetermined inclination direction with respect to an extension direction of the grating pattern and an arrangement direction of the grating pattern. Thus, manufacturing cost may be reduced, and the three dimensional shape measurement apparatus may be easily managed.

Abstract: The present invention provides systems and methods for obtaining a three-dimensional (3D) representation of one or more light sources inside a sample, such as a mammal. Mammalian tissue is a turbid medium, meaning that photons are both absorbed and scattered as they propagate through tissue. In the case where scattering is large compared with absorption, such as red to near-infrared light passing through tissue, the transport of light within the sample is described by diffusion theory. Using imaging data and computer-implemented photon diffusion models, embodiments of the present invention produce a 3D representation of the light sources inside a sample, such as a 3D location, size, and brightness of such light sources.

Abstract: Described is a method and apparatus for obtaining additional information from an object and a method for surface imaging and three-dimensional imaging. Single lens, single aperture, single sensor system and stereo optic systems are enhanced via selective filtering, use of defocusing information, use of an addressable pattern, image matching, and combinations thereof.

Abstract: An optical e.g. laser triangulation sensor is disclosed in which a configuration of an output light beam is controlled using a mask (19) in front of a light source. The configuration may include a plurality of coplanar spatially separated planar light beams. The mask may be movable to provide different light beam configurations. Masking parts of the light beam enables unwanted features on the measurement surface to be omitted. Also disclosed is a guide element (200) for an optical sensor for facilitating hole diameter measurement. The guide element has contact surfaces (212, 214, 216) lying on a virtual conical surface which abut the hole edge to enable consistent placement of the light beam with respect to the hole centre. Also disclosed is a guide element (300) for an optical sensor having an aperture for framing surface features (e.g. rivet) to permit accurate location of the light beam therewith.

Abstract: An apparatus, method, and program for measuring the three-dimensional shape of an object by analyzing an optical pattern projected onto the object includes a line sensor and an image analysis unit. The line sensor reads the target object, onto which the optical pattern is projected. The image analysis unit analyzes the optical pattern in the image read by the line sensor based on a spatial fringe analysis method, and the image analysis unit computes the three-dimensional shape information on the target object. The phase of a pixel included in an image taken of the optical pattern is determined based on the brightness values of the pixel and at least one neighboring pixel in the image; thus the height information of the object can be determined. In addition, the height of the target object at a given position can be computed based on how much the phase of the optical pattern projected onto a certain position of the object is shifted from a reference phase.

Abstract: The present invention relates to three-dimensional shape detection. In the present invention, a plurality of types of pattern lights formed of a series of alternate light and dark patterns are projected onto an object in a time series, an image of the object onto which each pattern light is projected is taken, a plurality of luminance images are generated, a code image having certain codes assigned to the pixels is generated in accordance with a result of threshold processing of the plurality of luminance images with respect to a certain threshold; and the three-dimensional shape of the object is calculated.

Abstract: A pattern measurement method includes: acquiring sectional shapes of a first pattern corresponding to process parameters, respectively; using the acquired sectional shapes to calculate predicted spectral waveforms which would be obtained when light is applied to the first pattern, and adding information on the corresponding process parameters to the calculated predicted spectral waveforms, respectively, to form a waveform library; setting a process parameter to obtain a desired shape, and acquiring an actual spectral waveform of a second pattern actually created from the first pattern using the set process parameter; performing waveform matching between the actual spectral waveform and the predicted spectral waveforms to acquire matching scores for respective waveform matching, and calculating an optimum process parameter providing the maximum matching score; generating an optimum pattern sectional shape corresponding to the optimum process parameter to measure the optimum pattern sectional shape.

Abstract: The invention relates to a device for the contactless detection of a three-dimensional contour, comprising a projector with an imaging element and a projection lens for depicting a stripe pattern that is generated on the imaging element in an object space. The invention further comprises a camera arrangement for the surveillance of the object space from two different directions, having two camera lenses. The projector and the camera arrangement are housed together in a measurement head that can be handheld. The invention further relates to a method for detecting a three-dimensional contour using said device.

Abstract: The shape and orientation of rigid or nearly rigid moveable bodies are determined using a shape characterization. Sensors capture a plurality of representations of different perspectives of the body that are analyzed to determine a bounding volume of the body. The shape of the body is determined from the bounding volume. The position of the body is determined using tracking devices that sense the position of the body. The bounding volume and position information are combined to define the shape and orientation in space of the body, and in particular the position of a point of interest on the body.

Abstract: An optical metrology model for a structure to be formed on a wafer is developed by characterizing a top-view profile and a cross-sectional view profile of the structure using profile parameters. The profile parameters of the top-view profile and the cross-sectional view profile are integrated together into the optical metrology model. The profile parameters of the optical metrology model are saved.

Abstract: The invention relates to a sensor for measuring the surface of an object, having a contrasting unit (3) for projecting a pattern onto the surface of the object, and having a camera (4) for recording of the pattern projected onto the surface of the object, in which the contrasting unit (3) has an LED projector (5). To achieve high precision and great robustness, the camera (4) and the LED projector (5) are located in the longitudinal direction. In addition, respective deflecting mirrors (8, 11) are assigned to the camera (4) and the LED projector (5) and are located on opposite ends, in the longitudinal direction of the sensor (1), of the housing (2) of the sensor (1).

Abstract: A profilometry apparatus is provided. The profilometry apparatus includes a fringe projection device configured to project a fringe pattern on an object and an optical unit configured to capture an image of a distorted fringe pattern modulated by the object. The profilometry apparatus also includes a signal processing unit configured to process the captured image from the optical unit to filter noise from the image and to obtain real-time estimation of parameters associated with manufacture or repair of the object.

Abstract: The present invention is a system and method for creating a three-dimensional model of a surface comprising a light source 1.2 that projects a pattern of continuous line segments onto the surface, wherein each line segment is coded with a unique pattern along the line segment, a detector 1.3 that records an image of the surface with said projected pattern, and a computer for transforming said image to a three-dimensional model of the surface utilizing said projected pattern.

Abstract: A method serves for the determination of the 3D coordinates of an object (2). A fringe pattern is projected onto the object (2) in the method. The light reflected by the object (2) is recorded and evaluated. To improve such a method, the fringe pattern is projected onto the object (2) by an imaging element (only FIGURE).

Abstract: A method and system for full-field fringe-projection for 3-D surface-geometry measurement, referred to as “triangular-pattern phase-shifting” is disclosed. A triangular grey-scale-level-coded fringe pattern is computer generated, projected along a first direction onto an object or scene surface and distorted according to the surface geometry. The 3-D coordinates of points on the surface are calculated by triangulation from distorted triangular fringe-pattern images acquired by a CCD camera along a second direction and a triangular-shape intensity-ratio distribution is obtained from calculation of the captured distorted triangular fringe-pattern images. Removal of the triangular shape of the intensity ratio over each pattern pitch generates a wrapped intensity-ratio distribution obtained by removing the discontinuity of the wrapped image with a modified unwrapping method. Intensity ratio-to-height conversion is used to reconstruct the 3-D surface coordinates of the object.

Abstract: A measuring apparatus of this invention comprises: a projector; a camera; a generator that generates, from a photographed image of a fringe pattern projected by the projector at a time of calibration onto each of surfaces, first tuples, each including coordinates of a point on a light receiving plane (LRP) of the camera, light intensity of the point and the height of the surface; a converter that converts the light intensity to a phase angle of the projected fringe pattern (PFP), and generates second tuples, each including the coordinates of the point on the LRP, the phase angle and the height of the surface; a hypersurface generator that generates data representing a tensor product type composite hypersurface (TPTCH) from data of the second tuples; an extractor that extracts data of third tuples, each including coordinates of a point on the LRP and light intensity from a photographed image of a fringe pattern projected by the projector at a time of measurement onto an object to be measured; a second converte

Abstract: The present invention uses ISTS to measure trenches with near- or sub-micron width. The trenches can be etched in a thin film on in a silicon substrate. One step of the method is exciting the structure by irradiating it with a spatially periodic laser intensity pattern in order to generate surface acoustic waves. Other steps are diffracting a probe laser beam off the thermal grating to form a signal beam; detecting the signal beam as a function of time to generate a signal waveform; determining surface acoustic wave phase velocity from the waveform; and determining at least one property of the trench structures based on the dependence of surface acoustic wave phase velocity on the parameters of the structure.

Abstract: The invention relates to a device for producing a pattern on a surface for measuring, using a projector and a slide. The invention also relates to various advantageous embodiments of the measuring system.