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:
May. 02, 1995
Filed:
Aug. 18, 1993
Rudolph M Snoeren, Eindhoven, NL;
Jan W Slotboom, Eindhoven, NL;
U.S. Philips Corporation, New York, NY (US);
Abstract
An x-ray examination apparatus includes an imaging arrangement, devised for performing fluoroscopy. Which has image sensors that are efficiently optically coupled with an x-ray sensitive radiation conversion screen. Consequently, the image sensors produce an electrical signal having a high signal-to-noise ration when low doses of x-radiation are administered. An x-ray conversion screen is provided with a tapetum filter so as to concentrate light in the forward direction. Furthermore, the x-ray conversion screen is preferably fitted with a light reflecting layer for reflecting light that has been reflected by the tapetum filter, said light reflecting layer being transparent for x-radiation. Further concentration of light in the forward direction is achieved by placing a light-transparent material having a suitable refractive index between the radiation conversion screen and lenses that concentrate the light onto the image sensors. Semiconductor image sensors in the form of charge-coupled devices are provided for converting a visible image into an electronic video signal. In order to improve the effectiveness of the CCDs, weak avalanching is applied so as to increase both sensitivity and signal-to-noise ratio of the sensors.