US4658410A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Stereo X-ray subtraction apparatus
Assignee: Siemens AG
•
Filing: 1984-10-12
•
Granted: 1987-04-14
•
Expires: 2004-10-12
Abstract
Abstract A stereo X-ray subtraction apparatus has a stereo X-ray system and an X-ray image intensifier television chain in which, for each channel, the video signals of successive stereo partial images are summed in a weighted fashion in a first image memory, the output of the first image memory being supplied to a first input of a first subtraction stage, with the output of the first image memory in the other channel being supplied to a second input of the first subtraction stage, the output of the first subtraction stage being supplied to a second image memory and to a first input of a second subtraction stage, and the output of the second image memory being supplied to a second input of the second subtraction stage. The outputs of the second subtraction stages for each channel are supplied to a display unit for displaying the resulting stereo image.
Inventors
- 👤 Jorg Haendle
- 👤 Wolfgang Maass
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 05:32
CPC Classifications
H; H04; H04N; H04N5/00; H04N5/30; H04N5/32; H04N5/3205
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
215 words
In a stereo X-ray apparatus having a means for generating two X-ray beams directed at an examination subject, an X-ray image intensifier, a video means for generating a video signal from said X-ray image intensifier consisting of alternating signals from said two X-ray beams, and a stereo display means, the improvement of a processing circuit having two stereo channels interconnected between said video means and said stereo display means comprising for each stereo channel: a means for weighting and summing successive video signals received from said video means; a first storage means for storing the weighted and summed video signals; a first subtraction means having a first input connected to the output of said first storage means and a second input connected to the output of the first storage means in the other stereo channel for forming a difference between the signals at said first and second inputs; a second storage means connected to the output of the first subtraction means; and a second subtraction means having a first input connected to the output of said second storage means and a second input connected to the output of said first subtraction means for forming a difference between the signals at said first and second inputs, and having an output connected to said stereo display means.
Claim 2
Dependent Claim
215 words
In a stereo X-ray apparatus having a means for generating two X-ray beams directed at an examination subject, an X-ray image intensifier, a video means for generating a video signal from said X-ray image intensifier consisting of alternating signals from said two X-ray beams, and a stereo display means, the improvement of a processing circuit having two stereo channels interconnected between said video means and said stereo display means comprising for each stereo channel: a means for weighting and summing successive video signals received from said video means; a first storage means for storing the weighted and summed video signals; a first subtraction means having a first input connected to the output of said first storage means and a second input connected to the output of the first storage means in the other stereo channel for forming a difference between the signals at said first and second inputs; a second storage means connected to the output of the first subtraction means; and a second subtraction means having a first input connected to the output of said second storage means and a second input connected to the output of said first subtraction means for forming a difference between the signals at said first and second inputs, and having an output connected to said stereo display means.
Claim 3
Dependent Claim
85 words
The improvement of claim 1 wherein said means for weighting and summing comprises: a first multiplier means connected to said video means for receiving said video signals therefrom; a second multiplier means having an input connected to an output of said first storage means; and an adder having a first input connected to the output of said first multiplier means and a second input connected to the output of said second multiplier means, and an output connected to an input of said first storage means.
Claim 4
Dependent Claim
21 words
The improvement of claim 2 wherein said first multiplier means consists of two multiplier stages respectively connected in each stereo channel.
Claim 5
Dependent Claim
21 words
The improvement of claim 2 wherein said first multiplier means consists of a single multiplier stage common to both stereo channels.
Claim 6
Dependent Claim
19 words
The improvement of claim 2 wherein each of said first and second multiplier means has a different weighting factor.
Claim 7
Dependent Claim
32 words
The improvement of claim 2 wherein said first multiplier means has a constant weighting factor and wherein said second multiplier means has a weighting factor of one minus said constant weighting factor.
Claim 8
Dependent Claim
33 words
The improvement of claim 1 wherein said first storage means has an input image frequency and an output image frequency, and wherein said input image frequency is less than said output image frequency.
Claim 9
Dependent Claim
61 words
The improvement of claim 1 wherein said processing circuit further comprises for each stereo channel a characteristic curve memory interconnected between the output of a first storage means in one of said channels and said second input of said first subtraction means in the other of said stereo channels for attenuating a signal at the output of said first storage means.
References Cited (Backward Citations)
DE1762875A1
Cited
US4064530A
Cited
US4350998A
Cited
EP0088356A1
Cited
US4507681A
Cited
US4578802A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1990-04-13 | 1990-10-13 | 1991-04-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-04-13 | 1994-10-13 | 1995-04-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-04-13 | 1998-10-13 | 1999-04-14 | $7700.00 | Window Closed / Lapsed |