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US5091925A Expired / Lapsed US ⏱️ 0.0 years remaining

X-ray diagnostics installation with spatial frequency filtering

Assignee: Siemens AG
•
Filing: 1990-10-26
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Granted: 1992-02-25
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Expires: 2010-10-26
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Abstract

Abstract An x-ray diagnostics installation has an x-ray tube and an image processing and display system which includes a video camera connected to the x-ray image intensifier, an image memory, a spatial frequency filter and a monitor. A motion detector is connected to the image memory and to the video camera and controls operation of the spatial frequency filter to vary the filter effect so that the filter effect is greater in transillumination image regions having little motion than in regions having a higher amount of motion.

Inventors

  • 👤 Joerg Haendle
  • 👤 Paul Marhoff

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-25 16:57
CPC Classifications
H; H04; H04N; H04N23/00; H04N23/30; Y; Y10; Y10S; Y10S378/00; Y10S378/901

Claims Analysis

Total Claims: 7
Claim 1
Independent Claim 126 words
An x-ray diagnositics installation comprising: an x-ray tube which generates an x-ray beam for penetrating an examination subject disposed in the x-ray beam; means for detecting an image consisting of x-rays attenuated by the examination subject; and video image processing means for converting said x-ray image into video signals forming a video image, said video image processing means including means for spatial frequency high-pass filtering and means for detecting motion in said video image, said means for detecting motion generating a signal dependent on the degree of motion and being connected to said means for spatial frequency high-pass filtering for varying the high-pass filter effect so that said high-pass filter effect is greater for video images having little motion than for video images having greater motion.
Claim 2
Dependent Claim 126 words
An x-ray diagnositics installation comprising: an x-ray tube which generates an x-ray beam for penetrating an examination subject disposed in the x-ray beam; means for detecting an image consisting of x-rays attenuated by the examination subject; and video image processing means for converting said x-ray image into video signals forming a video image, said video image processing means including means for spatial frequency high-pass filtering and means for detecting motion in said video image, said means for detecting motion generating a signal dependent on the degree of motion and being connected to said means for spatial frequency high-pass filtering for varying the high-pass filter effect so that said high-pass filter effect is greater for video images having little motion than for video images having greater motion.
Claim 3
Dependent Claim 33 words
An x-ray diagnostics installation as claimed in claim 1 wherein said video image processing means further includes a temporal low-pass filter connected to an output of said means for spatial frequency high-pass filtering.
Claim 4
Dependent Claim 55 words
An x-ray diagnostics installation as claimed in claim 2 wherein said motion detector is connected to said temporal low-pass filter for controlling the filter effect of said temporal low-pass filter so that said temporal low-pass filter has a greater filter effect for video images with little motion than for video images having a greater motion.
Claim 5
Dependent Claim 60 words
An x-ray diagnostics installation as claimed in claim 1 wherein said spatial frequency high-pass filter means comprises a filter circuit having an output connected to a mixing stage having a second input to which said video signals are supplied without filtering, said mixing stage having a variable mixing ratio controlled by said output signal of said means for detecting motion.
Claim 6
Dependent Claim 73 words
An x-ray diagnostics installation as claimed in claim 1 wherein said means for spatial frequency high-pass filtering comprises a filter circuit having an output connected to a variable gain amplifier, and a mixing stage to which an output of said variable gain amplifier is supplied and to which said video signals are also supplied without filtering, said output signal of said means for detecting motion controlling the gain of said variable gain amplifier.
Claim 7
Dependent Claim 29 words
An x-ray diagnostics installation as claimed in claim 1 wherein said means for spatial frequency high-pass filtering includes a spatial frequency high-pass filter which is a storage tube system.

References Cited (Backward Citations)

GB1128852A Cited
DE3007620A1 Cited
US4677478A Cited
US4745458A Cited
US4939758A Cited
US4873573A Cited
US4845561A Cited
US4847909A Cited
US4941169A Cited
US4860104A Cited
US4985767A Cited
US5025316A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1995-02-24 1995-08-26 1996-02-25 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1999-02-24 1999-08-26 2000-02-25 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2003-02-24 2003-08-26 2004-02-25 $7700.00 Window Closed / Lapsed

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