Abstract: A sheet material processing unit (10) is described. It comprises an upper tool (18) and a lower tool (14), wherein the upper tool (18) and the lower tool (14) are configured to interact with each other in order to process sheet material (26). Furthermore, a camera unit (40) is provided which is arranged such that it is able to simultaneously capture a portion of the upper tool (18) comprising a first opening (28) and a portion of the lower tool (14) lying behind the first opening (28) for aligning the tools (14, 18). The sheet material processing unit (10) additionally comprises a first and a second set of light sources which are distinct from one another and are configured for subsequently illuminating the portions to be captured. Moreover, methods for assessing an alignment of the upper tool (18) with respect to the lower tool (14) and with respect to the sheet material (26) are presented.

Abstract: This invention is about an imaging system that uses conventional cameras and a single laser line to perform quality control at the output of a converting machine or a press. The system uses several cameras distributed over the width of the printed sheets. Thanks to the laser line, it can reconstruct the complete image of the printed matter even when the sheets are not perfectly flat or at varying height, compensating geometric as well as photometric distortions. The use of conventional cameras results in a cost effective system.

Abstract: An image capturing system (10), and a corresponding method, for determining the position of an embossed structure (30) on a sheet element (4) moved though a viewing area (18). It includes a camera (12) adapted for capturing a line image of the surface of the sheet element (4) in the viewing area (18), and an illumination unit (14) with a plurality of light sources (20, 21, . . . ) each adapted for illuminating the viewing area (18). The light sources (20, 21, . . . ) are arranged at different inclinations with respect to the viewing area (18). An image evaluation unit (16) determines an inclination-related parameter for the surface of the sheet element (4) in the viewing area (18) across the viewing area (18).

Abstract: This invention is about an imaging system that uses conventional cameras and a single laser line to perform quality control at the output of a converting machine or a press. The system uses several cameras distributed over the width of the printed sheets. Thanks to the laser line, it can reconstruct the complete image of the printed matter even when the sheets are not perfectly flat or at varying height, compensating geometric as well as photometric distortions. The use of conventional cameras results in a cost effective system.

Abstract: A surface inspection system for inspecting the surface of sheet elements present in an inspection area: The system includes two light sources arranged adjacent each other on opposite sides of an illumination plane, and a camera for capturing line images of the inspection area along a viewing plane. The illumination plane and the viewing plane are arranged on opposite sides of a median plane perpendicular to an inspection plane. The angle between the illumination plane and the median plane is the same as the angle between the viewing plane and the median plane. In a method of using the system, the first light source illuminates the sheet element before the second light sources does. An image evaluation unit compares the captured line images with each other.

Abstract: A surface inspection system (10) for inspecting the surface of sheet elements (4) present in an inspection area (20). The system includes an image evaluation unit (18), a camera (12), a dark-field illuminator (14) and a bright-field illuminator (16). The image evaluation unit (18) subtracts a line image captured under bright-field illumination conditions from a line image captured under dark-field illumination conditions.

Abstract: A quality control station (2) for a sheet element processing machine, having at least one camera (6) arranged for capturing images of sheet elements (4) transported through the quality control station (2), and further having an illumination unit (5) with at least one light emitter (16) and two reflectors (12, 14), the illumination unit (5) directing light onto a viewing area of the camera (6) such that the illumination intensity is constant despite changing media thickness. An illumination unit for such quality control station is disclosed.

Abstract: A surface inspection system (10) for inspecting the surface of sheet elements (2) present in an inspection area (5): The system includes an image evaluation unit (18), two light sources (12, 14) arranged adjacent each other on opposite sides of an illumination plane (O11) and oriented for illuminating the inspection area (5), and a camera (16) for capturing line images (I12, I14) of the inspection area (5) along a viewing plane (O16). The illumination plane (O11) and the viewing plane (O16) are arranged on opposite sides of a median plane (M) which is perpendicular to an inspection plane. The angle (?) between the illumination plane (O11) and the median plane (M) is the same as the angle (?) between the viewing plane (O16) and the median plane (M).

Abstract: A quality control station (2) for a sheet element processing machine, having at least one camera (6) arranged for capturing images of sheet elements (4) transported through the quality control station (2), and further having an illumination unit (5) with at least one light emitter (16) and two reflectors (12, 14), the illumination unit (5) directing light onto a viewing area of the camera (6) such that the illumination intensity is constant despite changing media thickness. An illumination unit for such quality control station is disclosed.

Abstract: A surface inspection system (10) for inspecting the surface of sheet elements (4) present in an inspection area (20). The system includes an image evaluation unit (18), a camera (12), a dark-field illuminator (14) and a bright-field illuminator (16). The image evaluation unit (18) subtracts a line image captured under bright-field illumination conditions from a line image captured under dark-field illumination conditions.

Abstract: An image capturing system (10), and a corresponding method, for determining the position of an embossed structure (30) on a sheet element (4) moved though a viewing area (18). It includes a camera (12) adapted for capturing a line image of the surface of the sheet element (4) in the viewing area (18), and an illumination unit (14) with a plurality of light sources (20, 21, . . . ) each adapted for illuminating the viewing area (18). The light sources (20, 21, . . . ) are arranged at different inclinations with respect to the viewing area (18). An image evaluation unit (16) determines an inclination-related parameter for the surface of the sheet element (4) in the viewing area (18) across the viewing area (18).

Abstract: A device for analyzing the topography of a surface (2) of a substrate (1) travelling on a substantially planar course with axes X, Y and Z defining an orthonormal frame of reference of the space. The surface (2) is substantially parallel to the plane XY. A device (10) for structured lighting of the surface (2) engages with a device (20) for measuring light backscattered by the surface (2) in order to analyze topography of the surface(2) during travel of the substrate (1). The lighting device (10) projecting a light beam (F) with an angle of incidence ‘a’ onto the surface (2), to form a plurality ‘n’ of luminous streaks (S1, S2, . . . Sn) thereon. Each luminous streak (S) forms an angle ‘b’ with the axis X1. The measurement device (20) includes a linear camera located in a plane P secant to the plane XY and the plane XZ, the intersection of the plane P with the plane XY forming angles.

Abstract: A system, method, and method of manufacturing directed to an optical device with an efficient optical illumination. The optical illumination can be provided by tilting a light source and using a refractive lens to direct the light onto a surface. Alternatively, the optical illumination can be provided using total internal reflection with a conical light pipe and a curvatured entrance and exit surface.

Abstract: A system, method, and method of manufacturing directed to an optical device with an efficient optical illumination. The optical illumination can be provided by tilting a light source and using a refractive lens to direct the light onto a surface. Alternatively, the optical illumination can be provided using total internal reflection with a conical light pipe and a curvatured entrance and exit surface.

Abstract: Device for detecting patterns on a travelling substrate, namely on a substrate being deposited on a sheet or on web matter, wherein the substrate is a metallized foil travelling in a travelling direction. The device comprises a housing for a first incidental beam issued from a first source of light, a second incidental beam issued from a second source of light, an optical measuring system, a photosensitive sensor respectively delivering beams reflected from the substrate and an electronic unit connected to a communication port. The optical measuring system is telecentric, the first incidental beam crosses a telecentric lighting system and the second incidental beam crosses an oblique lighting system.

Abstract: Scanning device (1) for register marks (21, 22, 31, 32) printed onto a substrate (2) travelling into a polychrome printing machine. This device comprises at least one light source (3, 4) enlightening, onto the substrate (2), a lighting area (5) crossed by the register marks (21, 22, 31, 32), an optic (6) which allows obtaining onto a photosensitive element (7) the images of said register marks named as a plurality of portions (8) successively scanned with a certain scanning rate, as well as a microprocessor (9) driving the light of the light source (3, 4) and controlling electric pulses issued by pixels (17) of the photosensitive element (7). The source (3, 4) enlightens the lighting area (5) of the substrate (2) with at least one modulation of its color and/or of its intensity during the simultaneous or sequential scanning of at least two register marks. (21, 22, 31, 32).

Abstract: Device for detecting patterns on a travelling substrate, namely on a substrate being deposited on a sheet or on web matter, wherein the substrate is a metallized foil travelling in a travelling direction. The device comprises a housing for a first incidental beam issued from a first source of light, a second incidental beam issued from a second source of light, an optical measuring system, a photosensitive sensor respectively delivering beams reflected from the substrate and an electronic unit connected to a communication port. The optical measuring system is telecentric, the first incidental beam crosses a telecentric lighting system and the second incidental beam crosses an oblique lighting system.

Abstract: Scanning device (1) for register marks (21, 22, 31, 32) printed onto a substrate (2) travelling into a polychrome printing machine. This device comprises at least one light source (3, 4) enlightening, onto the substrate (2), a lighting area (5) crossed by the register marks (21, 22, 31, 32), an optic (6) which allows obtaining onto a photosensitive element (7) the images of said register marks named as a plurality of portions (8) successively scanned with a certain scanning rate, as well as a microprocessor (9) driving the light of the light source (3, 4) and controlling electric pulses issued by pixels (17) of the photosensitive element (7). The source (3, 4) enlightens the lighting area (5) of the substrate (2) with at least one modulation of its color and/or of its intensity during the simultaneous or sequential scanning of at least two register marks. (21, 22, 31, 32).

Abstract: An optical device for the spectral analysis of a light source which comprises a spectrograph assembly including a dispersive element, and a classical collimator. The spectrograph assembly supplies a complete intermediate spectrum at the object focus of the classical collimator and the classical collimator reforms, at its image focus, an image of the dispersive element. The spectrograph assembly is preferably a Czerny-Turner or other type of spectrograph comprising an entry slit, two juxtaposed concave mirrors of the same focal length and a dispersive element placed strictly in the common focal plane of the two mirrors. Most preferably, the classical collimator is the first mirror of the second, similar spectrograph assembly. The device is most advantageous in that it is readily useable for both simultaneous and sequential spectroscopy.

Abstract: A spark generator suitable for use in an optical emission spectrometer, and capable of generating a spark in a spark gap formed between an electrode and a sample to be analyzed, comprises a generator for generating a current of programmable amplitude in the spark gap in each of a series of discrete time intervals. The spark generator according to the invention is advantageous when compared with conventional spark generators in that it enables a higher degree of choice and control in the form of the spark. In particular, it enables the amplitudes of various portions of the spark to be independently varied, thus permitting the shape of the spark to be tailored to the particular analysis being performed. Also described are methods of optical emission spectroscopy which make use of the advantageous properties of the spark generator.