Abstract: The present invention relates to radiography, including medical radiography, specifically to the apparatus for controlling the technical characteristics of digital radiographic devices, and is intended to maintain self-diagnostics of digital X-ray detectors. The self-diagnostics system of digital X-ray detectors comprises a radiographic screen positioned in the radiation pathway from the radiographic source, an optical transfer system for transmitting an image from the screen to the photosensitive CCD-matrix-based sensor, and incorporates at least three test structures installed in the emission plane of a radiographic screen. The technical result is achieved due to the fact that the test structures are positioned outside the radiographic screen emitting surface and are provided with controlled sources of primary radiation installed so that each test structure is located in the direct ray path from the said sources.

Abstract: The invention is aimed at providing a lens having a wider angle of view, increased relative aperture, and higher quality of images.

Abstract: The inventions (variants) are intended for improvement of calibration precision of digital X-ray apparatuses: computed tomographs, as well as digital X-ray apparatuses equipped with C-arm and U-arm type stands, which method is based on calculation of mechanical instability of the stand.