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:
Feb. 07, 1995
Filed:
Nov. 26, 1993
Shigemi Fujiwara, Tochigiken, JP;
Kabushiki Kaisha Toshiba, Kanagawa, JP;
Abstract
An X-ray diagnostic apparatus includes: an X-ray tube; an X-ray controller for controlling a dose of X-rays generated by the X-ray tube; an image intensifier for converting X-rays radiated by the X-ray tube and passed through an object to be diagnosed, into an optical image; an optical system through which the optical image is passed; an image forming device for transducing the optical image obtained through the optical system into electric signals, the image forming device being provided with Knee characteristics such that photoelectric transduction characteristics into the electric signals has a point of inflection beyond which gradient thereof is reduced; a memory device for storing the electric signals outputted by the image forming device; an image displaying unit for processing the electric signals of the memory device for display of diagnosis information of the object to be diagnosed; an interest region determining section for determining a region of interest with respect to the diagnosis information displayed on the image display unit; and a luminous energy control section for controlling the dose of the X-rays through the X-ray controller on the basis of pixel values of the image forming device obtained in the determined region of interest, in such a way that values on the photoelectric transduction characteristics are always kept lower than a value at the point of inflection.