US3700329A - Radiographic reduction system - Google Patents

Radiographic reduction system Download PDF

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Publication number
US3700329A
US3700329A US168116A US3700329DA US3700329A US 3700329 A US3700329 A US 3700329A US 168116 A US168116 A US 168116A US 3700329D A US3700329D A US 3700329DA US 3700329 A US3700329 A US 3700329A
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Prior art keywords
film
record
radiographic
image
gradient portion
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Expired - Lifetime
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US168116A
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English (en)
Inventor
Robert P Mason
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AFP ACQUISITION Corp
LOG ETRONICS Inc
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Logetronics Inc
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Assigned to LOGETRONICS CORPORATION, reassignment LOGETRONICS CORPORATION, CHANGE OF NAME (SEE DOCUMENT FOR DETAILS). 09/21/87 Assignors: AFP ACQUISITION CORPORATION
Assigned to BANK OF NEW YORK COMMERCIAL CORPORATION, THE reassignment BANK OF NEW YORK COMMERCIAL CORPORATION, THE SECURITY INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: AFP ACQUISITION CORPORATION
Assigned to AFP ACQUISITION CORPORATION reassignment AFP ACQUISITION CORPORATION ASSIGNMENT OF ASSIGNORS INTEREST. Assignors: LOGETRONICS, INC.
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    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03B—APPARATUS OR ARRANGEMENTS FOR TAKING PHOTOGRAPHS OR FOR PROJECTING OR VIEWING THEM; APPARATUS OR ARRANGEMENTS EMPLOYING ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ACCESSORIES THEREFOR
    • G03B42/00—Obtaining records using waves other than optical waves; Visualisation of such records by using optical means
    • G03B42/02—Obtaining records using waves other than optical waves; Visualisation of such records by using optical means using X-rays
    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03B—APPARATUS OR ARRANGEMENTS FOR TAKING PHOTOGRAPHS OR FOR PROJECTING OR VIEWING THEM; APPARATUS OR ARRANGEMENTS EMPLOYING ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ACCESSORIES THEREFOR
    • G03B1/00—Film strip handling
    • G03B1/42—Guiding, framing, or constraining film in desired position relative to lens system
    • G03B1/48—Gates or pressure devices, e.g. plate
    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03B—APPARATUS OR ARRANGEMENTS FOR TAKING PHOTOGRAPHS OR FOR PROJECTING OR VIEWING THEM; APPARATUS OR ARRANGEMENTS EMPLOYING ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ACCESSORIES THEREFOR
    • G03B15/00—Special procedures for taking photographs; Apparatus therefor
    • G03B15/003—Apparatus for photographing CRT-screens
    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03B—APPARATUS OR ARRANGEMENTS FOR TAKING PHOTOGRAPHS OR FOR PROJECTING OR VIEWING THEM; APPARATUS OR ARRANGEMENTS EMPLOYING ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ACCESSORIES THEREFOR
    • G03B27/00—Photographic printing apparatus
    • G03B27/72—Controlling or varying light intensity, spectral composition, or exposure time in photographic printing apparatus
    • G03B27/725—Optical projection devices wherein the contrast is controlled electrically (e.g. cathode ray tube masking)
    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03B—APPARATUS OR ARRANGEMENTS FOR TAKING PHOTOGRAPHS OR FOR PROJECTING OR VIEWING THEM; APPARATUS OR ARRANGEMENTS EMPLOYING ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ACCESSORIES THEREFOR
    • G03B27/00—Photographic printing apparatus
    • G03B27/72—Controlling or varying light intensity, spectral composition, or exposure time in photographic printing apparatus
    • G03B27/80—Controlling or varying light intensity, spectral composition, or exposure time in photographic printing apparatus in dependence upon automatic analysis of the original

Definitions

  • a typical radiographic (X-ray) film normally employs a double emulsion, coated respectively on opposing sides of a transparent film base, to record two superimposed images which, in their composite, can have a density range up to 4.0, Le, a light transmission ratio of 10,000zl.
  • a typical document recording film e.g., 35 mm. film, which has been used in other environments to store records for rapid access, is normally provided with only a single emulsion coatinghaving a limited brightness acceptance range, such as 100:1.
  • optical systems which are required to produce the reduced intermediate record.
  • Such optical systems typically employ multi-elements which inherently tend to exhibit some light scattering properties even when of the highest quality. Such light scattering tends to degrade the tonal separation of the intermediate image, particularly in those portions of the record corresponding to the most dense (black) portions of the original radiograph. If the reproduction system contemplates, moreover, that the image in the intermediate record is later to be remagnified, either for purposes of obtaining a copy or for projection viewing, additional light scattering and flare problems tend to further degrade the final image with resultant loss of vital information.
  • the present invention recognizing these problems of the prior art, is concerned with the provision of a new radiographic reduction system, capable of producing a faithful reproduction of an original radiograph at reducedsize (e.g., 4 inches by 5 inches, or in a 35 mm format) which lends itself to more convenient storage and automated rapid access techniques; and is particularly directed to the production of such a reduced intermediate image which retains all vital information present in the original radiograph.
  • reducedsize e.g. 4 inches by 5 inches, or in a 35 mm format
  • the present invention produces the desirable results described above in a radiographic reduction system which combines the characteristics of known unsharp masking apparatuses with the contrast characteristics of special, commercially available, film employed heretofore for other purposes.
  • the record film employed is selected to exhibit, when properly processed,
  • a dual-gradient contrast characteristic having a relatively low contrast gradient portion and a relatively higher contrast gradient portion.
  • One such film presently commercially available, is known as Kodak Gravure Copy film, processed under carefully controlled conditions, e.g., for 7 minutes at 680 F. in Kodak D-76 developer. Films of this type, so processed, exhibit a relatively low contrast gradient portion having a gamma slope of approximately 0.5, or ranging from approximately 0.35 to 0.7, and a relatively higher contrast gradient portion having a gamma slope in the range of approximately 1 to 2.
  • the unsharp masking apparatus which may correspond to one, or combinations, of the systems described in US. Pat. Nos. 2,842,025, 3,036,497 and 3,115,807. More particularly, the unsharp masking apparatus employed may be of the so-called intensity modulation type, as typified by Craig et al US. Pat. No. 3,115,807 for Electronic Masking, or it may be of the so-called velocity modulation type, as typified by Folse US. Pat. No. 3,036,497.
  • a sheet of radiographic film having an image therein (which, of course, depending upon the nature of the film and the type of image recorded may have a density range varying from up to a value substantially in excess of 2.0, e.g., 3.5 or 4.0) is positioned closely adjacent the face of the light generating means (e.g., a cathode ray tube) forming a portion of the unsharp masking apparatus.
  • Light preferably in the form of a scanning spot, passes through successive incremental portions of the image in the radiograph and is then transmitted, through an optical system of suitable resolving quality, onto a supported photosensitive record film having the dual-gradient contrast characteristic described previously.
  • control circuits forming a portion of the aforementioned unsharp masking apparatus; and said control circuits in turn control either the intensity of the light spot or its scanning velocity, to effect unsharp masking of the image over a selected range of image densities which is closely coordinated with the slope of the relatively higher contrast gradient portion of the record film characteristic.
  • any image densities in excess of approximately 2.0 in said radiographic film are recorded, unmasked, on the lower contrast gradient portion of the record film characteristic.
  • Any image densities in the radiographic film in the partial range between 0 and approximately 2.0 are recorded, with unsharp marking, on the higher contrast gradient portion of the record film characteristic.
  • the gross contrast gradient of the overall system is linearized to a composite transfer characteristic having a gamma slope corresponding to the slope of the lower contrast gradient portion in said record film.
  • the total density range in the original film ranging from 0 to as much as 4.0, is now linearly compressed and recorded on the record film over a total density range of 0 to 2.0.
  • the system of the present invention can enhance detail over those portions of the density range in which the unsharp masking apparatus is operative.
  • This feature of the invention enables the ratio of detail contrast versus gross contrast existing in the original radiograph to be adjusted with respect to the characteristics of both the intermediate record film and any subsequent reproduction material.
  • the system enables the optical portions thereof to transfer image information without the addition of significant amounts of nonimage forming lens flare" which, of course, has been one of the major problems characterizing prior attempts to record images of such wide dynamic brightness range.
  • the present invention not only achieves the desired reduction and reproduction of information but, in many cases, actually makes it easier for a radiologist or other skilled person to interpret various portions of the image, particularly the very dense portions thereof, by eliminating the need to so-cal1ed hot light such portions during evaluation and/or diagnosis.
  • FIG. 1 is an illustrative diagram of a radiographic reduction system constructed in accordance with the present invention.
  • FIG. 2 is a graphical representation of the transfer characteristics of the masking system and related record film, illustrating their cooperative effect.
  • a radiographic reduction system constructed in accordance with the present invention comprises, as described earlier, the combination of an unsharp masking system and an intermediate record film having particular contrast characteristics.
  • the unsharp masking system may take various forms, including those of the prior patents identified earlier; but it must be understood that variations may be made in this respect, e.g., rather than employing cathode ray tube light sources, alternative scannable light sources such as lasers could be employed.
  • a cathode ray tube 10 provides a source of exposure illumination in the form of a scanning spot of light which is directed through a radiograph 11 mounted closely adjacent to the face of the cathode ray tube.
  • Light passing through the radiograph is depicted by broken lines 12 and is imaged, via an optical system 13 of suitable resolution characteristics, on record film 14 having the dual gradient characteristic described previously (and to be described subsequently in reference to FIG. 2).
  • Record film 14 is preferably retained in place by a vacuum platen 15 which operates to positively position all portions of the record film 14 at points of sharp focus relative to optics 13 and radiograph 11.
  • the record film 14 may take the form of cut sheets which are fed, by an appropriate mechanism (not shown), from a stack of unexposed film located to one side of the platen 15 onto said platen and then transferred to another stack of exposed sheets.
  • the record film 14 may take the form of a supply roll mounted at one side of the platen and operative to feed a length of record film past the platen 15 to a take-up roll.
  • the platen 15 may be stationary or, alternatively, may be mounted for indexing movement in X and/or Y directions if it is desired to record a number of images in side by side relation to one another on a given area of record film 14.
  • the unsharp masking system includes a light detector 16 which is adapted to monitor the light passing through radiograph 11.
  • Light detector 16 is illustrated in FIG. 1 as a photocell, but in normal course can take the form of a photomultiplier tube or other photo detector associated with appropriate fiber optics to permit the light detector 16 to be placed at any convenient location in the entire equipment.
  • the output of light detector 16 operates a control circuit 17 which may take a variety of forms such as have been described in the previously identified patents; and control circuit 17 operates in turn, in dependence upon the amount of light detected at 16, to control the operation of cathode ray tube so as to achieve unsharp masking.
  • control circuit 17 can be connected to the electron gun of tube 10 to achieve intensity modulation (see Craig et a], U.S. Pat. No. 3,115,807) or the output of circuit 17 can be used to control the deflection circuits of the cathode ray tube to achieve velocity modulation (as described in Folse U.S. Pat. No. 3,036,497).
  • control circuit 17 include provision for adjusting the percentage of unsharp masking which is achieved by the overall system.
  • Craig et al, U.S. Pat. No. 3,1 15,807 describes one circuit for achieving this type of adjustment in conjunction with an intensity modulation unsharp masking apparatus. If a velocity modulation apparatus of the type contemplated by Folse U.S. Pat. No. 3,036,497 is employed, control of the percentage of unsharp masking can be achieved by modifying the circuit shown in the Folse patent to include provision for adjusting the input signal supplied to the horizontal (fast) deflection yoke illustrated in that patent. Adjustments of these general types have been diagrammatically illustrated in FIG. 1 at 18.
  • the unsharp masking apparatus diagrammatically illustrated in FIG. 1, in the particular application illustrated in FIG. 2, is depicted as operating, in cooperation with the higher contrast gradient portion of record film 14, over a density range of 2.0 to 1.0.
  • the transfer characteristic of the unsharp masking apparatus 10, l618 cooperates with the transfer characteristic of the higher contrast gradient portion of the record film 14 to produce a net transfer characteristic which has a new slope that is effectively a linear extension of the lower contrast portion of the record film gradient. This will become more readily apparent by reference to FIG. 2.
  • Curve 20 illustrates a range of densities which can be found in original radiograph 1 1.
  • the term idealized radiograph has been employed in FIG. 2 since, as will be appreciated by those skilled in the art, curve 20 (and curve 40 to be described) do not include the shoulder and toe portions which are characteristic of all photographic materials.
  • a point 21 on curve 20 (designated by the intersection of broken line e with said curve 20) is intended to represent the inherent density which is always present in the radiographic material, reflecting the film base as well as the fog density resulting, for example, from processing of the film; and all image densities which are present in the radiograph are superimposed on this minimum density value, between point 21 and a density value which may be as high as 3.5 or 4.0.
  • Curve 20 is depicted as substantially linear; and, for the reasons already described, it is necessary, in order to avoid loss of vital image information, to preserve substantial linearity in any intermediate record, copy, or projected image made from the radiograph 1 1.
  • FIG. 2 further includes a curve 30 which depicts the transfer characteristic of an electronic printer (or unsharp masking apparatus) of one of the types described earlier.
  • the electronic printer is capable of achieving unsharp masking over a range of densities between 0.0 and about 2.0 in the original radiograph.
  • the actual percentage of unsharp masking can be varied between 0 percent (depicted at 31) and values approaching percent (depicted at 32).
  • the percentage of unsharp masking should be adjusted to some value intermediate 0 percent and 100 percent, with the actual adjustment being dependent upon the gamma slope of the higher contrast portion of the record film l4 characteristic.
  • it has been assumed that the percentage of unsharp masking has been adjusted to 50 percent as designated at 33.
  • the unsharp maskin g apparatus merely acts as a conventional light source operating to transmit a fixed and predetermined amount of light through the radiograph in the density range 2.0 to 4.0. This is characteristic of the cathode ray tube unsharp masking systems described in the prior patents identified earlier, and is highly desirable for the present application.
  • Curve 40 in FIG. 2 depicts the idealized dualgradient contrast characteristic of record film 14.
  • Characteristic curve 40 includes a lower portion which exhibits a relatively low contrast gradient having a gamma slope of approximately 0.5 (as depicted in FIG. 2) and an upper portion having a higher contrast gradient which may have a gamma slope of 1.0 to 2.0.
  • FIG. 2 includes a fourth curve, designated 50, which depicts the resultant densities achieved in the intermediate film 14 due to the net transfer characteristic produced by the combined effects of the dual-gradient material 14 and the unsharp masking effect achieved by the electronic exposing apparatus.
  • curve 50 is substantially linear and has a gamma slope of approximately 0.5 throughout.
  • broken lines a-e, inclusive have been included in FIG. 2, extending between corresponding points on curves 20, 30, 40, and 50.
  • Broken lines a, b and correspond respectively to densities of 4.0, 3.0 and 2.0 in the original radiograph and, as illustrated by the intersection of these three lines a-c with curve 30, images having densities in the range 2.0 to 4.0 in the original radiograph are not subject to any unsharp masking and are exposed on the relatively low contrast gradient portion of intermediate or record film 14 in the density range of approximately 0 to 1.0 in said record film.
  • Broken lines a, b, 0, when traced successively between curves 20, 30, 40 and 50 indicate, in effect, that image densities in the original radiograph,
  • Broken line d is intended to depict any typical density in the range between point 21 (identified earlier) and a density of approximately 2.0 in the original radiograph. lmages having densities in this range are subjected to unsharp masking and, in addition, are recorded on the higher contrast gradient portion of the record film characteristic. More particularly, if line d is traced from curve 20 to curve 33 (representing the assumed transfer characteristic of an electronic printer adjusted to achieve 50 percent unsharp masking), and then downwardly to curve 40, it will be seen that densities corresponding to broken line d are subject to both unsharp masking and to the effect of the higher contrast gradient portion of the record film 14.
  • Broken line e represents the minimum density 21 which is always present in the radiograph due to the density of the film base and development fog.
  • the exposure of densities at this minimum level 21 should be so adjusted, by calibration of the electronic printer control circuit 17, that they are recorded at a density of approximately 2.0 on the higher contrast gradient portion of the record film 14. This determines the maximum density which will exist in the record film 14 and assures that no radiographic information will be lost due to underexposure of record film 14.
  • the image produced in the record film is of reverse polarity to that in radiograph 11, i.e., it is what has sometimes been termed a black-bones image.
  • Such images are not acceptable to many radiologists for viewing; and therefore the record film 14 is actually an intermediate" film which is used to produce a final copy or other reproduction which is of acceptable polarity.
  • the intermediate film can be used for purposes of storing the radiograph in reduced form, and for obtaining rapid access thereto; and such films are less likely to be removed from the files since they are themselves of unacceptable image polarity.
  • Copies, of acceptable polarity can be made from the intermediate film on any film or paper of suitable brightness acceptance range; and paper copies, in particular, may be made rapidly and inexpensively for relatively wide scale distribution if desired, e.g., as a teaching adjunct or for use by a plurality of facilities that may have cognizance of a particular patient.
  • a radiographic reduction system comprising means for supporting a photosensitive record film having a dual-gradient contrast characteristic exhibiting a relatively low contrast gradient portion and a relatively higher contrast gradient portion, an unsharp masking apparatus comprising means for generating a moving spot of light, a sheet of radiographic film having an image thereon the density range of which may be as great as 0.0 to 4.0, said radiographic film sheet being supported between said light generating means and said record film, optical means disposed in the light transmission path between said sheet of radiographic film and said record film for producing, at said record film, a reduced size image of the image in said radiographic film as said moving spot passes successively through all incremental portions of said radiographic film image, said unsharp masking apparatus being calibrated to record the film base plus fog density, in said radiographic film sheet, on said record film at a density of approximately 2.0, any image densities in said radiographic film between the partial range of about 0 to approximately 2.0 being recorded on the higher contrast gradient portion said record film characteristic, control means for monitoring the amount of light which has passed through said radio
  • control'means comprises means operative to vary the intensity of said electron beam.
  • control means comprises means operative to vary the scanning velocity of said electron beam.
  • said unsharp masking apparatus includes means for adjusting the percentage of masking effected thereby.

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  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Spectroscopy & Molecular Physics (AREA)
  • Radiography Using Non-Light Waves (AREA)
  • Exposure Or Original Feeding In Electrophotography (AREA)
  • Projection-Type Copiers In General (AREA)
  • Image Processing (AREA)
  • Image Analysis (AREA)
  • Printers Or Recording Devices Using Electromagnetic And Radiation Means (AREA)
  • Silver Salt Photography Or Processing Solution Therefor (AREA)
  • Apparatus For Radiation Diagnosis (AREA)
  • Dot-Matrix Printers And Others (AREA)
  • Facsimile Scanning Arrangements (AREA)
US168116A 1971-08-02 1971-08-02 Radiographic reduction system Expired - Lifetime US3700329A (en)

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US16811671A 1971-08-02 1971-08-02

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JP (1) JPS5126263B2 (enrdf_load_html_response)
BE (1) BE779564A (enrdf_load_html_response)
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Cited By (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3967893A (en) * 1974-04-29 1976-07-06 Xerox Corporation Illuminating apparatus
US4433345A (en) * 1981-06-19 1984-02-21 Loge/Dunn Instruments, Inc. Video image recording methods and devices
US4457618A (en) * 1982-07-01 1984-07-03 Polaroid Corporation Optical system for use in electronic enlarger
US4511925A (en) * 1982-08-16 1985-04-16 Mackenroth Iii Joseph R High intensity ultraviolet light video imaging apparatus
US4530011A (en) * 1981-06-19 1985-07-16 Loge/Dunn Instruments, Inc. Apparatus for maintaining of a cathode ray tube image within the light acceptance range of a photographic film
US4676618A (en) * 1985-02-16 1987-06-30 Agfa-Gevaert Aktiengesellschaft Device for producing photographic pictures with a plane film platform
US4742397A (en) * 1986-01-16 1988-05-03 Polaroid Corporation System and method for adjusting image brightness in electronic printer
EP0343935A3 (en) * 1988-05-23 1991-01-30 Innovative Imaging Sciences Inc. Enchancement method and system for x-ray imaging
US5043824A (en) * 1989-10-27 1991-08-27 Brother Kogyo Kabushiki Kaisha Color mask recording apparatus with light components scanned at set exposure amount conversion rates
US5045949A (en) * 1987-08-18 1991-09-03 Fuji Photo Film Co., Ltd. Image recording apparatus for recording still image and letters without distortion
US6288995B1 (en) * 1997-09-30 2001-09-11 Jerry W. Bohn Non-mechanical recording and retrieval apparatus
US6434262B2 (en) * 1993-09-29 2002-08-13 Shih-Ping Wang Computer-aided diagnosis system and method
US6466689B1 (en) * 1991-11-22 2002-10-15 Arch Development Corp. Method and system for digital radiography
US20050116181A1 (en) * 2003-10-29 2005-06-02 Jerry Bohn Non-mechanical recording and retrieval apparatus

Families Citing this family (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS55148657A (en) * 1980-03-06 1980-11-19 Daihatsu Motor Co Ltd Hemming method for body structure of automobile
JPS57200716A (en) * 1981-06-04 1982-12-09 Yukiyoshi Kawabata Locking device for screw clamping elastic body
JPS5928337A (ja) * 1982-08-09 1984-02-15 Hitachi Ltd プロジエクシヨンアライナ
JPS62123376U (enrdf_load_html_response) * 1986-01-29 1987-08-05
JPS6368276A (ja) * 1986-09-11 1988-03-28 Ohara Kinzoku Kogyo Kk 一個の溶接用通電電極を用いたスポット溶接装置

Cited By (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3967893A (en) * 1974-04-29 1976-07-06 Xerox Corporation Illuminating apparatus
US4433345A (en) * 1981-06-19 1984-02-21 Loge/Dunn Instruments, Inc. Video image recording methods and devices
US4530011A (en) * 1981-06-19 1985-07-16 Loge/Dunn Instruments, Inc. Apparatus for maintaining of a cathode ray tube image within the light acceptance range of a photographic film
US4457618A (en) * 1982-07-01 1984-07-03 Polaroid Corporation Optical system for use in electronic enlarger
US4511925A (en) * 1982-08-16 1985-04-16 Mackenroth Iii Joseph R High intensity ultraviolet light video imaging apparatus
US4676618A (en) * 1985-02-16 1987-06-30 Agfa-Gevaert Aktiengesellschaft Device for producing photographic pictures with a plane film platform
US4742397A (en) * 1986-01-16 1988-05-03 Polaroid Corporation System and method for adjusting image brightness in electronic printer
US5045949A (en) * 1987-08-18 1991-09-03 Fuji Photo Film Co., Ltd. Image recording apparatus for recording still image and letters without distortion
EP0343935A3 (en) * 1988-05-23 1991-01-30 Innovative Imaging Sciences Inc. Enchancement method and system for x-ray imaging
US5043824A (en) * 1989-10-27 1991-08-27 Brother Kogyo Kabushiki Kaisha Color mask recording apparatus with light components scanned at set exposure amount conversion rates
US6466689B1 (en) * 1991-11-22 2002-10-15 Arch Development Corp. Method and system for digital radiography
US6434262B2 (en) * 1993-09-29 2002-08-13 Shih-Ping Wang Computer-aided diagnosis system and method
US6288995B1 (en) * 1997-09-30 2001-09-11 Jerry W. Bohn Non-mechanical recording and retrieval apparatus
US20050116181A1 (en) * 2003-10-29 2005-06-02 Jerry Bohn Non-mechanical recording and retrieval apparatus

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NL7203260A (enrdf_load_html_response) 1973-02-06
DE2236863A1 (de) 1973-03-01
CA972206A (en) 1975-08-05
NL149012B (nl) 1976-03-15
JPS5126263B2 (enrdf_load_html_response) 1976-08-05
BE779564A (fr) 1972-06-16
GB1354044A (en) 1974-06-05
CH556557A (de) 1974-11-29
DE2236863B2 (de) 1976-12-02
JPS4825523A (enrdf_load_html_response) 1973-04-03

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Effective date: 19870902

Owner name: BANK OF NEW YORK COMMERCIAL CORPORATION, THE, NEW

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Effective date: 19870902