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US4394737A Expired / Lapsed US ⏱️ 0.0 years remaining

Method of processing radiographic image

Assignee: Fujifilm Holdings Corp
•
Filing: 1980-07-11
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Granted: 1983-07-19
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Expires: 2000-07-11
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Abstract

Abstract In radiography, a plurality of radiographic films are used for recording radiographic images of an object viewed from the same direction. For instance, a stack of radiographic films stacked together with intensifying screens is exposed to X-rays passing through an object to record the images on the films simultaneously. Alternatively, the plurality of radiographic films are exposed to X-rays passing through the object one by one with the object held still at a position. The images on the plurality of radiographic films are superposed together by electrical signal processing means to obtain an image having averaged density. Then, the gradient of the gradation of the averaged image is enhanced. The radiographic films may be stacked together with self-supporting intensifying screens to reduce the thickness of the stack of the films and intensifying screens when recording the radiographic images. Further, double-side coated intensifying screens may be used together with the stack of the films to reduce the thickness of the stack of the films and intensifying screens when recording the radiographic images.

Inventors

  • 👤 Takao Komaki
  • 👤 Seiji Matsumoto

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-28 01:47
CPC Classifications
H; H05; H05G; H05G1/00; H05G1/08; H05G1/60; G; G03; G03C; G03C5/00; G03C5/16

Claims Analysis

Total Claims: 16
Claim 1
Independent Claim 61 words
In radiographic image recording system, a method of processing a radiographic image comprising steps of recording radiographic images of an object viewed from the same direction on a plurality of radiographic films, superposing and averaging the images on the plurality of radiographic films to obtain an averaged image having averaged density, and enhancing the gradient of gradation of the averaged image.
Claim 2
Dependent Claim 61 words
In radiographic image recording system, a method of processing a radiographic image comprising steps of recording radiographic images of an object viewed from the same direction on a plurality of radiographic films, superposing and averaging the images on the plurality of radiographic films to obtain an averaged image having averaged density, and enhancing the gradient of gradation of the averaged image.
Claim 3
Dependent Claim 27 words
A method of processing a radiographic image according to claim 1 wherein said radiographic images of an object are recorded on the plurality of radiographic films sequentially.
Claim 4
Dependent Claim 27 words
A method of processing a radiographic image according to claim 1 wherein said radiographic images of an object are recorded on the plurality of radiographic films simultaneously.
Claim 5
Dependent Claim 30 words
A method of processing a radiographic image according to claim 3 wherein said radiographic images of an object are recorded on a stack of the plurality of radiographic films simultaneously.
Claim 6
Independent Claim 27 words
A method of processing a radiographic image according to one of claims 1, 2, 3, and 4 wherein said images are recorded by a slit recording method.
Claim 7
Independent Claim 112 words
A method of processing a radiographic image in a radiographic image recording system comprising steps of recording radiographic images of an object viewed from the same direction on a plurality of radiographic films, superposing and averaging the images on the plurality of radiographic films to obtain an averaged image having averaged density, obtaining an unsharp mask density Dus corresponding to a super-low frequency of said averaged image, and performing an operation represented by a formula of Dorg+β(Dorg-Dus) where Dorg is the density of the image and β is an emphasis coefficient, whereby the gradient of gradation of the averaged image is enhanced with respect to a frequency component above said super-low frequency.
Claim 8
Independent Claim 112 words
A method of processing a radiographic image in a radiographic image recording system comprising steps of recording radiographic images of an object viewed from the same direction on a plurality of radiographic films, superposing and averaging the images on the plurality of radiographic films to obtain an averaged image having averaged density, obtaining an unsharp mask density Dus corresponding to a super-low frequency of said averaged image, and performing an operation represented by a formula of Dorg+β(Dorg-Dus) where Dorg is the density of the image and β is an emphasis coefficient, whereby the gradient of gradation of the averaged image is enhanced with respect to a frequency component above said super-low frequency.
Claim 9
Dependent Claim 22 words
A method according to claim 6 wherein said radiographic images of an object are recorded on the plurality of radiographic films sequentially.
Claim 10
Dependent Claim 22 words
A method according to claim 6 wherein said radiographic images of an object are recorded on the plurality of radiographic films simultaneously.
Claim 11
Dependent Claim 30 words
A method of processing a radiographic image according to claim 8 wherein said radiographic images of an object are recorded on a stack of the plurality of radiographic films simultaneously.
Claim 12
Independent Claim 47 words
A method of processing a radiographic image accordingn to one of claims 6, 7, 8, and 9 wherein said operation is performed by use of an unsharp mask having a modulation transfer function which falls below 0.5 in the super-low frequency range of 0.5 to 0.01 cycle/mm.
Claim 13
Independent Claim 42 words
A method of processing a radiographic image according to one of claims 6, 7, 8, and 9 wherein said emphasis coefficient β is changed according to the original density Dorg of the image or the unsharp mask density Dus of the image.
Claim 14
Independent Claim 27 words
A method of processing a radiographic image according to one of claims 6, 7, 8, and 9 wherein said images are recorded by a slit recording method.
Claim 15
Independent Claim 116 words
A method of processing a radiographic image in a radiographic image recording system comprising steps of recording radiographic images of an object viewed from the same direction on a plurality of radiographic films, superposing and averaging the images on the plurality of radiographic films to obtain an averaged image having averaged density, obtaining an unsharp mask density Dus corresponding to a super-low frequency of said radiographic images on the radiographic films, and performing an operation represented by a formula of Dorg+β(Dorg-Dus) where Dorg is the density of the image and β is an emphasis coefficient, whereby the gradient of gradation of the averaged image is enhanced with respect to a frequency component above said super-low frequency.
Claim 16
Independent Claim 116 words
A method of processing a radiographic image in a radiographic image recording system comprising steps of recording radiographic images of an object viewed from the same direction on a plurality of radiographic films, superposing and averaging the images on the plurality of radiographic films to obtain an averaged image having averaged density, obtaining an unsharp mask density Dus corresponding to a super-low frequency of said radiographic images on the radiographic films, and performing an operation represented by a formula of Dorg+β(Dorg-Dus) where Dorg is the density of the image and β is an emphasis coefficient, whereby the gradient of gradation of the averaged image is enhanced with respect to a frequency component above said super-low frequency.

References Cited (Backward Citations)

US1609703A Cited
US3988602A Cited
US4216526A Cited
US4276473A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1986-07-18 1987-01-17 1987-07-19 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1990-07-18 1991-01-17 1991-07-19 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1994-07-18 1995-01-17 1995-07-19 $7700.00 Window Closed / Lapsed

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