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:
Oct. 26, 1993
Filed:
Feb. 24, 1992
Yves Raverdy, Bas Bernin, FR;
Gerard Vieux, Grenoble, FR;
Francois Chareyre, St Egreve, FR;
Alain Tranchant, St Martin d'Heres, FR;
Thomson Tubes Electroniques, , FR;
Abstract
An image intensifying tube, such as a image intensifying tube which converts X-rays into a visible image, comprises a curved input screen which comprises a substrate that receives input radiation and a photocathode supported on the substrate, and an output screen which converts the electrons emitted by the photocathode into a visible image. In order to compensate for changes in luminosity due to the curvature of the input screen, an intermediary layer of radially variable thickness is deposited between the substrate and the photocathode. The intermediary layer is made from a material, such as indium oxide (In.sub.2 O.sub.3), which modifies the electron emitting characteristics of the photocathode as a function of the thickness the intermediary layer. Thus, a thicker intermediary layer near the center of the input screen will compensate for reduced luminosity at the edges of the screen.