The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jul. 03, 1990
Filed:
May. 04, 1989
Stephan G Rupp, Stolberg, DE;
Ulrich Schiebel, Aachen, DE;
U.S. Philips Corporation, New York, NY (US);
Abstract
A method is disclosed for producing a X-ray image by a photoconductor which converts X-rays into a charge pattern and which is uniformly charged prior to the X-ray exposure and is discharged during the X-ray exposure as a function of the intensity of the X-rays, the surface of the photoconductor being scanned to measure the charge density, for each pixel point there being formed an image value which is dependent on the discharge at the relevant pixel whereby dot-shaped artefacts in the X-ray image may appear. These artefacts are substantially removed by measuring the position of the fault locations on the photoconductor, storing the position of the fault locations and the variations of the artefacts caused thereby in the vicinity of the fault locations; determining during subsequent X-ray exposures the amplitude of the artefact caused by the fault location from the image values at the position of the fault location and at the edge of a zone surrounding the fault location, calculating the variation of the artefact in the X-ray image in the surrounding zone from the amplitude and the stored variation, and correcting the X-ray image accordingly.