Abstract: An x-ray detector comprises: a housing, including a cover removably fastened on a flange of a flanged base and forming a semi-hermetic seal therebetween, the flanged base including a bottom surface and the flange surrounding a perimeter of the bottom surface; and an x-ray imager positioned on the bottom surface, the x-ray imager including a scintillator and an image sensor, wherein the seal semi-hermetically encloses the x-ray imager in the housing, and is positioned nonadjacently to surfaces in contact with the x-ray imager. In this way, a simpler and less costly seal for a digital x-ray panel can be provide; furthermore, the seal is reusable and resealable, facilitating repair and refurbishment of the device.

Abstract: An x-ray detector comprises: a housing, including a cover removably fastened on a flange of a flanged base and forming a semi-hermetic seal therebetween, the flanged base including a bottom surface and the flange surrounding a perimeter of the bottom surface; and an x-ray imager positioned on the bottom surface, the x-ray imager including a scintillator and an image sensor, wherein the seal semi-hermetically encloses the x-ray imager in the housing, and is positioned nonadjacently to surfaces in contact with the x-ray imager. In this way, a simpler and less costly seal for a digital x-ray panel can be provide; furthermore, the seal is reusable and resealable, facilitating repair and refurbishment of the device.

Abstract: An image pick-up apparatus including an image sensor with a matrix of radiation-sensitive elements, notably a CCD image sensor, is provided with a control circuit for selecting gate electrodes as collecting gate electrodes or as isolating gate electrodes by application of an electric potential of suitable polarity. Groups of collecting gate electrodes are separated from one another by isolating gate electrodes. The surface area of such a group of collecting gate electrodes co-determines the modulation transfer function and hence the spatial resolution of the image sensor; this surface area, and hence the spatial resolution, can be adjusted by adjustment of the electric potentials. Notably the spatial resolution can be rendered dependent on the different modes of operation of the image pick-up apparatus, for example when the image pick-up apparatus forms part of an X-ray examination apparatus which is suitable for fluoroscopy as well as for making X-ray images.

Abstract: An X-ray examination apparatus comprises an X-ray detector (1) for deriving an optical image from an X-ray image. An image pick-up device (2) derives an image signal from the optical image. The image pick-up device (2) is provided with an image sensor (3,4) having a plurality of sensor elements. The effective surface area of the sensor elements differs for different optical spectral components of the optical image. The image pick-up device is provided with an adjusting system for selecting an optical spectral component. The image signal is derived from the selected optical spectral component.

Abstract: An X-ray examination apparatus comprises an X-ray detector 1 for deriving an image signal and a measurement signal from an X-ray image. The X-ray examination apparatus also includes an exposure control 2 for adjusting the X-ray examination apparatus on the basis of the measurement signal. The X-ray detector is arranged in such a manner that the measurement signal relates mainly to relevant image information in the X-ray image. The X-ray detector is notably provided with a conversion unit 22 for deriving an optical image from the X-ray image. An image sensor with an image pick-up section derives electrical charges from the optical image. The image pick-up section notably derives a measurement component from the electrical charges wherefrom the measurement signal is derived and the image pick-up section also derives an image component from the electrical charges wherefrom the image signal is derived.

Abstract: An X-ray examination apparatus includes an X-ray source (1) for irradiating an object (2) by means of an X-ray beam (3) in order to form an X-ray image. An optical image is derived from the X-ray image by means of an X-ray detector (4). The optical image is picked up by means of an image pick-up apparatus (5). The image pick-up apparatus (5) includes a plurality of image sensors (6, 7) for deriving separate electronic sub-image signals from the optical image. The image pick-up apparatus also includes a subtraction unit (8) for subtracting the electronic sub-image signals from one another. The image pick-up apparatus (5) also includes a control circuit (9) which is arranged to make integration periods of individual image sensors (7, 8) commence at instants which are spaced a waiting period apart. The difference signal represents changes in the X-ray image or, when the X-ray energy is changed during the waiting period, differences in X-ray absorption due to energy-dependency.

Abstract: In charge-coupled imaging devices it is generally necessary to provide zones (12) in the matrix with a contact. These zones may form part, for example, of a mechanism for draining charge, for example as a protection against overexposure. In the case of imaging devices with a horizontal readout register on one side of the matrix, these contacts can be provided on the opposite side. However, it is often desirable or even necessary, as in the case of imaging devices with four-quadrant readout, to provide such contacts on the same side as the horizontal readout register. To this end, a dummy line (14'-17') is provided in accordance with the invention between the matrix and the horizontal readout register (6), said dummy line having an electrode structure which leaves room for contact windows (22) to the zones (12).

Abstract: An X-ray examination apparatus (1) includes an X-ray source (2) and an X-ray image intensifier (5) for deriving an optical image from an X-ray image, which optical image is picked up by means of an image pick-up apparatus (6). The X-ray examination apparatus also includes an exposure-control system (7) for adjusting the X-ray source and/or the image pick-up apparatus on the basis of brightness values of a region of interest in the optical image. The exposure-control system includes a photodetector, for example a CCD sensor, for deriving a photodetector signal from the optical image and a photosensor for adjusting the sensitivity of the photodetector. The photodetector (9) includes an image pick-up section (11), an image memory (13) comprising separate sections, preferably including an intermediate memory (15). An electronic image in the image pick-up section is quickly transferred to an available storage section after which it is read out as an electronic image signal.

Abstract: In an image detection system having a CCD sensor, particularly for an x-ray examination apparatus, image read-out is substantially accelerated. This is achieved by discarding portions of the electronic image that is stored in the image storage-part of the CCD. Thus, only, portions of the image that contain relevant image information are converted into an electronic video signal.

Abstract: Accurately aligning opto-electronic image sensors with respect to a beam-splitter being comprised in an image sensing device is facilitated by incorporating an alignment pattern in the conductive metal stripes of the opto-electronic image sensors. When simultaneously viewed through the input face of the beam-splitter, alignment patterns of respective opto-electronic image sensors form a combined alignment patterns showing the accuracy of the alignment of the opto-electronic image sensors. By providing differences between pitches of the alignment patterns on either side of an axis of reflection, a combined alignment pattern is obtained showing various types of alignment errors, such as horizontal or vertical translation, or rotations. Quantification of alignment errors is facilitated by making use of vernier action in the combined alignment pattern.

Abstract: An imaging system includes an image pick-up device with an image sensor having a rectangular detection face which is subdivided into discrete detection sub-faces for converting a radiation intensity distribution on the detection face into an electric signal, the detection sub-faces being arranged in a matrix of n rows and p columns respectively dividing short and long sides of the detection face, an object plane and an optical system which images a radiation intensity distribution in a circle situated in the object plane onto an ellipse situated on the detection face in accordance with a compression factor m. The compression factor may be chosen so that the ellipse spans no more than p/2 columns of the detection face so that video images can be formed at twice the conventional rate. In the case of non-square detection sub-faces, the compression rate may be chosen so that the ellipse spans an equal number of rows and columns, thereby making each detection sub-face correspond to a square in the object plane.