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High-contrast X-ray image detecting apparatus

Assignee: Shimadzu Corp
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Filing: 1986-10-08
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Granted: 1988-08-02
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Expires: 2006-10-08
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Abstract

Abstract An X-ray image detecting apparatus devised so as to project an X-ray image of an object on a image receiving plane made of two-dimensionally arrayed picture elements with the object irradiated by many thin scanning X-ray beams. The beams, which penetrate the object, scan coincidentally a limited number of the picture elements of which they take a charge respectively, causing the time of scanning the whole area of the image receiving plane to be short. The image signals successively outputted from the picture elements are stored in a memory with only their respective maximum values selected. Thus, the image signals are made free from being adversely affected by the stray X-rays scattered from the inside of the object, and provide a high-contrast X-ray image.

Inventors

  • 👤 Motosada Kiri

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-02 08:15
CPC Classifications
A; A61; A61B; A61B6/00; A61B6/06; H; H04; H04N; H04N23/00; H04N23/30

Claims Analysis

Total Claims: 6
Claim 1
Independent Claim 278 words
An X-ray image detecting apparatus comprising: an X-ray source; a collimator plate placed between said X-ray source and an object whose X-ray image is to be detected, said collimator plate being provided with two-dimensionally arrayed X-ray collimating through holes to make a plurality of thin X-ray beams from widely diversing X-rays from said X-ray source; an X-ray image receiving means for converting an X-ray image projected thereon to an electric image signal, said X-ray image receiving means being devised so as to detect said X-ray image with the same divided into pixels so that said electric image signal may be outputted in the form of pixel signals from said X-ray image receiving means; a collimator plate displacing means for moving said collimator plate two-dimensionally in parallel to said X-ray image receiving means so that the same may be scanned by said thin X-ray beams made by said X-ray collimating through holes provided in said collimator plate; a memory means having addresses corresponding to said pixels for storing said electric image signal in the form of the pixel signals; and a signal comparator means for comparing, with regard to each of said addresses of said memory, a previously sampled and stored value of a pixel signal with a succeedingly sampled value of the pixel signal and replacing the contents of each address with a succeedingly sampled pixel signal if the latter value is larger than the former one, such that each of the addresses in said memory may finally store the maximum value of a corresponding pixel signal which varies showing a peak in the process of the scanning of a corresponding X-ray beam made by said collimator plate.
Claim 2
Dependent Claim 278 words
An X-ray image detecting apparatus comprising: an X-ray source; a collimator plate placed between said X-ray source and an object whose X-ray image is to be detected, said collimator plate being provided with two-dimensionally arrayed X-ray collimating through holes to make a plurality of thin X-ray beams from widely diversing X-rays from said X-ray source; an X-ray image receiving means for converting an X-ray image projected thereon to an electric image signal, said X-ray image receiving means being devised so as to detect said X-ray image with the same divided into pixels so that said electric image signal may be outputted in the form of pixel signals from said X-ray image receiving means; a collimator plate displacing means for moving said collimator plate two-dimensionally in parallel to said X-ray image receiving means so that the same may be scanned by said thin X-ray beams made by said X-ray collimating through holes provided in said collimator plate; a memory means having addresses corresponding to said pixels for storing said electric image signal in the form of the pixel signals; and a signal comparator means for comparing, with regard to each of said addresses of said memory, a previously sampled and stored value of a pixel signal with a succeedingly sampled value of the pixel signal and replacing the contents of each address with a succeedingly sampled pixel signal if the latter value is larger than the former one, such that each of the addresses in said memory may finally store the maximum value of a corresponding pixel signal which varies showing a peak in the process of the scanning of a corresponding X-ray beam made by said collimator plate.
Claim 3
Dependent Claim 31 words
An apparatus defined in claim 1, wherein said X-ray image receiving means is constituted with an X-ray image receiving plane made up of a two-dimensional array of pixel unit X-ray detectors.
Claim 4
Dependent Claim 59 words
An apparatus defined in claim 1, wherein said X-ray image receiving means consists of an assembly of an X-ray image intensifier and a TV camera optically coupled to said X-ray image intensifier, and wherein the electron beam scanning in said TV camera is performed not continuously, but intermittently to detect an X-ray image in the form of pixel signals.
Claim 5
Dependent Claim 22 words
An apparatus defined in claim 2, wherein said pixel unit X-ray detectors are elements capable of directly converting X-rays to electric signals.
Claim 6
Dependent Claim 29 words
An apparatus defined in claim 2, wherein each of said pixel unit X-ray detectors is a combination of an X-ray scintillator and a photosensor coupled to said X-ray scintillator.

References Cited (Backward Citations)

DE2452166A1 Cited
US4096391A Cited
JPS5767847A Cited
US4383327A Cited
US4493098A Cited
US4433427A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1991-08-02 1992-02-01 1992-08-02 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1995-08-02 1996-02-01 1996-08-02 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1999-08-02 2000-02-01 2000-08-02 $7700.00 Window Closed / Lapsed

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