US1961713A - X-ray observation apparatus - Google Patents

X-ray observation apparatus Download PDF

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US1961713A
US1961713A US599190A US59919032A US1961713A US 1961713 A US1961713 A US 1961713A US 599190 A US599190 A US 599190A US 59919032 A US59919032 A US 59919032A US 1961713 A US1961713 A US 1961713A
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light
rays
image
scanning
disc
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Luther G Simjian
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    • GPHYSICS
    • G02OPTICS
    • G02BOPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B27/00Optical systems or apparatus not provided for by any of the groups G02B1/00 - G02B26/00, G02B30/00
    • G02B27/02Viewing or reading apparatus
    • G02B27/022Viewing apparatus
    • G02B27/023Viewing apparatus for viewing X-ray images using image converters, e.g. radioscopes

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  • This invention relates, in general, to an apparatus or method of facilitating the observation of hidden organs of living creatures by means of the well known X-ray machine and is particularly adaptable for use by doctors in ldiagnosing the internal disorders of man and east.
  • the apparatus embodying the present inventive conception may be used in connection with the familiar X-ray fluorescent screen in which the subject, placed between the source of the X- rays and the screen, throws a sharp shadow on the glowing surface thereof.
  • the power of the X-rays to penetrate opaque matter depends primarily on the density or atomic weight of the cellular structure of the organisms under exposure, only changes in density of the light emitted from the body exposed to the action of the rays will be clearly brought out for observation on the fluorescent screen. Consequently, at the present time it is very diflicult to examine a patient under a fluoroscope because the doctor is only able to see the outlines of the denser organisms and bones on thescreen in a dim shadow form.
  • the invention has, for one of its main objects, the elimination of the present difliculties encountered both by the observer and the observed in this type of examination.
  • Another object of the invention is to provide an apparatus that will function to convert the present fluorescent screen image, depicted in shadow color tones of gray, black and white, so that the same will appear to view in primary colors such as red, yellow and blue and thereby make readily observable, by a distinct contrast, the lines of demarcation between organisms of varying densities.
  • the invention also contemplates the provision of an apparatus in which the observer may be able to examine the blood vessels of the patient in their natural color.
  • a fluorescent screen of the usual type is unable to depict to the eye of the observer any of the blood vessels of the subject because of the fine texture or relatively light density of the cellular structure of this portion of the body and consequently its inability to cast 5 deep shadows on the screen. Because of the increased visionary capabilities afi'orded the observer in the use of an apparatus constructed in accordance with the present invention, it is not necessary to utilize an intense X-ray discharge so that the patient may be subjected to a relative- 6O ly longer period of observation and thereby assist the doctor in arriving at the direct diagnosis of the case.
  • Fig. 1 is a diagrammatic representation of an overhead perspective view of an apparatus embodying the present invention and Fig. 2 is a side elevation of the apparatus as shown in Fig. 1.
  • the apparatus may be used with a standard fluoroscope, which comprises an X-ray tube 10 for directing the passage of rays therefrom upon a board or diaphragm 11 in front of which the subject or patient under observation takes a position in the location 12.
  • the fluorescent screen for the ordinary visual observation of the internal organisms is indicated at 13.
  • I preferably employ a suitable lead scanning disc, which the X-rays cannot penetrate, to explore the image on the fluorescent screen, this scanning disc being rotatably mounted and being equipped with closely situated holes or openings to obtain extreme accuracy in scanning the minute differences in tone color on the screen.
  • the scanning disc may be placed either between the X-ray tube and the fluoroscopic screen or between the screen and the point of observation associated with the apparatus. Also if desired, the use of the fluorescent screen as it is ordinarily employed may be obviated by placing a fluorescent substance such as barium platinocyanide or calcium tungstate in the openings of the scanning disc.
  • a suitably dimensioned image or picture may be transmitted by the scanning disc 14 and either the patient or the apparatus can be moved so that the body of the organism, which the doctor wishes to observe, may be brought within the range of his vision.
  • a lens system for redirecting the passage of the light rays scanned by the revolving disc 14 is indicated at 15.
  • three of such lenses are employed for the purpose of illustrat- 105 ing the inventive disclosure.
  • I also preferably locate, in the path of the direction of the light through each of the lenses, selective light sensitive arrangements responsive to different degrees of intensity of illumination.
  • Such arrangements 110 may comprise light filters and photo-electric cells of graduated light sensitivity.
  • each of the filters permits the penetration of a desired tone value of the light to which they are subjected.
  • filter 16 permits a complete penetration of all the light rays
  • filter 1'7 permits the penetration of the light of only the brilliant rays and rays of intermediate tone quality, or grayish color tone
  • filter 18 permits the penetration of only the brilliant tones.
  • only filter 16 would permit the passage of the darkest rays.
  • the intermediate filter 1'7 permits the penetration of the grayer tones also.
  • I For measuring the light intensities in each division of thesystem, I employ highly sensitive photoelectric cells as indicated at 19, each individual cell controlling or modulating an electric circuit by being connected electrically to a separate stage resistance coupled amplifier 20 and a color neon or other electronic gaseous light 21 such as argon or mercury vapor.
  • the said lights may be respectively constructed to emit red, yellow and blue light.
  • the neon lamps interpret or translate in terms of light the current variation in the amplifying circuits in response to the light impulses or variations afiecting the photoelectric cells of the apparatus.
  • the lens system at the receiving end of the apparatus is indicated at 22.
  • the rays from these lamps are then recombined to form a new image of exactly the contour of the original image by means of a second scanning disc in a manner similar to that employed in the art of television.
  • the receiving scanning disc is shown at 23, the same being rotated at synchronous speed to the scanning disc 14 through the motor driven gear system illustrated in the drawing at 24 or otherwise.
  • a viewing box for observation of the reconstructed image or picture, on the fluorescent screen, made by the receiving disc 23, is indicated at 25.
  • a magnifying lens 26 may be employed to enlarge the size of the image to the observer.
  • the amplifying power of each of the amplifiers 20 may be manually controlled either individually through handles 2'7, 28 or 29 or simultaneously, as desired, by the rack bar mechanism indicated at 30, which may be raised into mesh with pinions on the shafts of said handles or lowered at will by means such as cam 40.
  • the rack bar mechanism indicated at 30 may be raised into mesh with pinions on the shafts of said handles or lowered at will by means such as cam 40.
  • the invention also contemplates the possible utilization of the present apparatus so that any desired number of receiving discs 23, associated with neon lights electrically connected to the respective amplifiers 20, may be placed in different rooms to facilitate an individual examination by separate doctors of thesame patient at the same time.
  • an X-ray machine Inasmuch as many changes could obviously be made in the construction of the apparatus herein combination, an X-ray machine, a scanning disc for exploring the image produced by the rays on a fluorescent screen, a plurality of light intensity filters of diiferent degrees of light intensity selectively associated with the scanning disc, a photoelectric cell energized by the light penetrating each of the filters, amplifying means actuated by the impulses produced by each of the cells, a plurality of luminous gas tubes of different color characteristics individually brought into operation by the amplified impulses, and a second disc operated synchronously with the first named disc for combining the light emanations from the said tubes whereby a reconstructed image in distinctive colors is produced.
  • an X-ray machine a scanning disc for exploring the image produced by the rays on a fluorescent screen, a plurality of light intensity filters of different degrees of light intensity selectivity associated with the scanning disc, a photo-electric cell energized by the light penetrating each of the filters, amplifying means actuated by the impulses produced by each of the cells, means for varying the amplifying power of the respective amplifiers either individually or simultaneously, a plurality of luminous gas tubes of different color characteristics individually brought into operation by the amplified impulses, a scanning disc operated synchronously with the first named disc for combining the light emanations from the said tubes, and means for rendering visible the reconstructed colored image.
  • a fiuoroscope scanning means for exploring an image thereon, means for selectively filtering the scanned light rays according to light intensity, means for converting the filtered rays into electrical impulses, luminous gas tubes illuminated thereby and emanating light of different colors, and a second scanning means operated synchronously with said first named disc for reforming the original image in colors.
  • an X-ray machine a fluorescent screen associated therewith, scanning means for exploring an image produced on the screen, means for selectively filtering the scanned light rays according to light intensity, means for converting the filtered rays into electrical impulses, selective means for amplifying the impulses in each of the circuits, means actuated by the output of said selective means and comprising a plurality of gaseous tubes of difierent colors for reeonverting the impulses in each of the circuits to colored light emanations, and scanning means synchronously operated with respect to the first named scanning means for reforming the original image in colors.
  • a fiuoroscope scanning means for exploring an image thereon, means for selectively filtering the scanned light rays transmitted from said means according to light intensity, means for converting the said rays into electrical impulses, a plurality of tubes emanating light of 'ndividual colors individually actuated from said electrical impulses, and a scanning means synchronously operated with the first scanning means and adapted to receive light from said colored tubes.
  • Apparatus for increasing the effectiveness of X-ray observations comprising a scanning disc for scanning an image produced by X-rays, a plurality of light intensity sensitive devices oi. different degrees of sensitivity on which the small successive images thus obtained are thrown, a plurality of electric circuits modulated from said devices, means for controlling the instantaneous luminosity of a plurality of light sources of different color emission by said circuits, and means for recombining the colored light therefrom including a scanning disc operated synchronously with said other disc, reproducing in colors the original black and white X-ray image.
  • Apparatus for increasing the effectiveness of X-ray diagnosis comprising means for exploring the subject by an Xray beam passing through the subject and a. scanning disc, means for converting the X-ray penetrations into light rays, a plurality of photo-electric cells of different degrees of intensity selectivity operated from said light rays, a plurality of light sources of different color emission X-rayed from the output of said photo-electric cells, and means for recombining the colored light rays therefrom, reproducing in colors the original black and white X-ray image.

Description

June 5, 1934.
L. G. SIMJIAN 1,961,713 X-RAY OBSERVATION APPARATUS iled March 16, 1952 Q Q fl/IIWM 1 1 fi I! INVENTQIR 7 mm 6.5/ /J/AN.
Patented June 5, 1934 UNITED STATES PATENT OFFICE 1,961,713 X-RAY OBSERVATION APPARATUS Luther G. Simjian, New Haven, Conn. Application March 16, 1932, Serial No. 599,190 7 Claims. (01. 250-44) This invention relates, in general, to an apparatus or method of facilitating the observation of hidden organs of living creatures by means of the well known X-ray machine and is particularly adaptable for use by doctors in ldiagnosing the internal disorders of man and east.
The apparatus embodying the present inventive conception may be used in connection with the familiar X-ray fluorescent screen in which the subject, placed between the source of the X- rays and the screen, throws a sharp shadow on the glowing surface thereof. As the power of the X-rays to penetrate opaque matter depends primarily on the density or atomic weight of the cellular structure of the organisms under exposure, only changes in density of the light emitted from the body exposed to the action of the rays will be clearly brought out for observation on the fluorescent screen. Consequently, at the present time it is very diflicult to examine a patient under a fluoroscope because the doctor is only able to see the outlines of the denser organisms and bones on thescreen in a dim shadow form. For instance, if the doctor desires to observe further detail of an organ, such as the heart, it is necessary that the intensity of the X-rays be increased in order to'eifect a more complete penetration of the organ by the rays. This naturally diminishes the period of time that the subject or patient may be kept under examination without harm or discomfort resulting therefrom. The invention has, for one of its main objects, the elimination of the present difliculties encountered both by the observer and the observed in this type of examination.
Another object of the invention is to provide an apparatus that will function to convert the present fluorescent screen image, depicted in shadow color tones of gray, black and white, so that the same will appear to view in primary colors such as red, yellow and blue and thereby make readily observable, by a distinct contrast, the lines of demarcation between organisms of varying densities.
The invention also contemplates the provision of an apparatus in which the observer may be able to examine the blood vessels of the patient in their natural color. A fluorescent screen of the usual type is unable to depict to the eye of the observer any of the blood vessels of the subject because of the fine texture or relatively light density of the cellular structure of this portion of the body and consequently its inability to cast 5 deep shadows on the screen. Because of the increased visionary capabilities afi'orded the observer in the use of an apparatus constructed in accordance with the present invention, it is not necessary to utilize an intense X-ray discharge so that the patient may be subjected to a relative- 6O ly longer period of observation and thereby assist the doctor in arriving at the direct diagnosis of the case.
Other objects and advantages of the invention will become apparent as the description proceeds. 65,-
Referring to the drawing:
Fig. 1 is a diagrammatic representation of an overhead perspective view of an apparatus embodying the present invention and Fig. 2 is a side elevation of the apparatus as shown in Fig. 1.
Referring to the drawing the apparatus may be used with a standard fluoroscope, which comprises an X-ray tube 10 for directing the passage of rays therefrom upon a board or diaphragm 11 in front of which the subject or patient under observation takes a position in the location 12. The fluorescent screen for the ordinary visual observation of the internal organisms is indicated at 13. In the apparatus comprising the present invention, I preferably employ a suitable lead scanning disc, which the X-rays cannot penetrate, to explore the image on the fluorescent screen, this scanning disc being rotatably mounted and being equipped with closely situated holes or openings to obtain extreme accuracy in scanning the minute differences in tone color on the screen. The scanning disc may be placed either between the X-ray tube and the fluoroscopic screen or between the screen and the point of observation associated with the apparatus. Also if desired, the use of the fluorescent screen as it is ordinarily employed may be obviated by placing a fluorescent substance such as barium platinocyanide or calcium tungstate in the openings of the scanning disc. A suitably dimensioned image or picture may be transmitted by the scanning disc 14 and either the patient or the apparatus can be moved so that the body of the organism, which the doctor wishes to observe, may be brought within the range of his vision.
A lens system for redirecting the passage of the light rays scanned by the revolving disc 14 is indicated at 15. In this instance three of such lenses are employed for the purpose of illustrat- 105 ing the inventive disclosure. I also preferably locate, in the path of the direction of the light through each of the lenses, selective light sensitive arrangements responsive to different degrees of intensity of illumination. Such arrangements 110 may comprise light filters and photo-electric cells of graduated light sensitivity. Preferably each of the filters permits the penetration of a desired tone value of the light to which they are subjected. As illustrated in the drawing of this case filter 16 permits a complete penetration of all the light rays, filter 1'7 permits the penetration of the light of only the brilliant rays and rays of intermediate tone quality, or grayish color tone, and filter 18 permits the penetration of only the brilliant tones. In other words, only filter 16 would permit the passage of the darkest rays. It will be understood that the intermediate filter 1'7 permits the penetration of the grayer tones also.
For measuring the light intensities in each division of thesystem, I employ highly sensitive photoelectric cells as indicated at 19, each individual cell controlling or modulating an electric circuit by being connected electrically to a separate stage resistance coupled amplifier 20 and a color neon or other electronic gaseous light 21 such as argon or mercury vapor. The said lights may be respectively constructed to emit red, yellow and blue light. The neon lamps interpret or translate in terms of light the current variation in the amplifying circuits in response to the light impulses or variations afiecting the photoelectric cells of the apparatus. The lens system at the receiving end of the apparatus is indicated at 22. The rays from these lamps are then recombined to form a new image of exactly the contour of the original image by means of a second scanning disc in a manner similar to that employed in the art of television. The receiving scanning disc is shown at 23, the same being rotated at synchronous speed to the scanning disc 14 through the motor driven gear system illustrated in the drawing at 24 or otherwise. A viewing box for observation of the reconstructed image or picture, on the fluorescent screen, made by the receiving disc 23, is indicated at 25. A magnifying lens 26 may be employed to enlarge the size of the image to the observer.
In order to obtain a very high degree of observation of the organism to be diagnosed, the amplifying power of each of the amplifiers 20 may be manually controlled either individually through handles 2'7, 28 or 29 or simultaneously, as desired, by the rack bar mechanism indicated at 30, which may be raised into mesh with pinions on the shafts of said handles or lowered at will by means such as cam 40. By this means, a particular tone of light on the fluorescent screen, converted to electrical energy by the photoelectric cells, may be more highly amplified and consequently brought more readily to the view of the doctor than the other tones in the original image. By selective manipulation of the handles 2'7, 28 and 29 the doctor may bring to view in distinct contrasting tonal qualities the image on the fluorescent screen. Because of the relatively higher sensitivity afforded. the doctor in measuring and difierentiating between slight changes of the original tonal color on the screen, it is possible for him to observe the blood vessels of the patient.
The invention also contemplates the possible utilization of the present apparatus so that any desired number of receiving discs 23, associated with neon lights electrically connected to the respective amplifiers 20, may be placed in different rooms to facilitate an individual examination by separate doctors of thesame patient at the same time.
Inasmuch as many changes could obviously be made in the construction of the apparatus herein combination, an X-ray machine, a scanning disc for exploring the image produced by the rays on a fluorescent screen, a plurality of light intensity filters of diiferent degrees of light intensity selectively associated with the scanning disc, a photoelectric cell energized by the light penetrating each of the filters, amplifying means actuated by the impulses produced by each of the cells, a plurality of luminous gas tubes of different color characteristics individually brought into operation by the amplified impulses, and a second disc operated synchronously with the first named disc for combining the light emanations from the said tubes whereby a reconstructed image in distinctive colors is produced.
2. In a device of the character described, in combination, an X-ray machine, a scanning disc for exploring the image produced by the rays on a fluorescent screen, a plurality of light intensity filters of different degrees of light intensity selectivity associated with the scanning disc, a photo-electric cell energized by the light penetrating each of the filters, amplifying means actuated by the impulses produced by each of the cells, means for varying the amplifying power of the respective amplifiers either individually or simultaneously, a plurality of luminous gas tubes of different color characteristics individually brought into operation by the amplified impulses, a scanning disc operated synchronously with the first named disc for combining the light emanations from the said tubes, and means for rendering visible the reconstructed colored image.
3. In a device of the character described, in combination, a fiuoroscope, scanning means for exploring an image thereon, means for selectively filtering the scanned light rays according to light intensity, means for converting the filtered rays into electrical impulses, luminous gas tubes illuminated thereby and emanating light of different colors, and a second scanning means operated synchronously with said first named disc for reforming the original image in colors.
4. In a device of the character described, in combination, an X-ray machine, a fluorescent screen associated therewith, scanning means for exploring an image produced on the screen, means for selectively filtering the scanned light rays according to light intensity, means for converting the filtered rays into electrical impulses, selective means for amplifying the impulses in each of the circuits, means actuated by the output of said selective means and comprising a plurality of gaseous tubes of difierent colors for reeonverting the impulses in each of the circuits to colored light emanations, and scanning means synchronously operated with respect to the first named scanning means for reforming the original image in colors.
5. In a device of the character described, in combination, a fiuoroscope, scanning means for exploring an image thereon, means for selectively filtering the scanned light rays transmitted from said means according to light intensity, means for converting the said rays into electrical impulses, a plurality of tubes emanating light of 'ndividual colors individually actuated from said electrical impulses, and a scanning means synchronously operated with the first scanning means and adapted to receive light from said colored tubes.
6. Apparatus for increasing the effectiveness of X-ray observations comprising a scanning disc for scanning an image produced by X-rays, a plurality of light intensity sensitive devices oi. different degrees of sensitivity on which the small successive images thus obtained are thrown, a plurality of electric circuits modulated from said devices, means for controlling the instantaneous luminosity of a plurality of light sources of different color emission by said circuits, and means for recombining the colored light therefrom including a scanning disc operated synchronously with said other disc, reproducing in colors the original black and white X-ray image.
7. Apparatus for increasing the effectiveness of X-ray diagnosis comprising means for exploring the subject by an Xray beam passing through the subject and a. scanning disc, means for converting the X-ray penetrations into light rays, a plurality of photo-electric cells of different degrees of intensity selectivity operated from said light rays, a plurality of light sources of different color emission X-rayed from the output of said photo-electric cells, and means for recombining the colored light rays therefrom, reproducing in colors the original black and white X-ray image.
LUTHER G. SIMJIAN.
US599190A 1932-03-16 1932-03-16 X-ray observation apparatus Expired - Lifetime US1961713A (en)

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Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2469206A (en) * 1946-11-14 1949-05-03 Gen Electric X-ray absorption photometer
US2477307A (en) * 1946-11-09 1949-07-26 Mackta Leo Combined x-ray and fluoroscopic apparatus
US2539196A (en) * 1948-07-22 1951-01-23 Westinghouse Electric Corp Radiation detector
US2593925A (en) * 1948-10-05 1952-04-22 Sheldon Edward Emanuel Device for color projection of invisible rays
US2670401A (en) * 1948-06-15 1954-02-23 Weinberg Marvin X-ray diagnostic apparatus
US2730566A (en) * 1949-12-27 1956-01-10 Bartow Beacons Inc Method and apparatus for x-ray fluoroscopy
US5033073A (en) * 1987-11-24 1991-07-16 Boeing Company System for radiograhically inspecting a relatively stationary object and related method

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2477307A (en) * 1946-11-09 1949-07-26 Mackta Leo Combined x-ray and fluoroscopic apparatus
US2469206A (en) * 1946-11-14 1949-05-03 Gen Electric X-ray absorption photometer
US2670401A (en) * 1948-06-15 1954-02-23 Weinberg Marvin X-ray diagnostic apparatus
US2539196A (en) * 1948-07-22 1951-01-23 Westinghouse Electric Corp Radiation detector
US2593925A (en) * 1948-10-05 1952-04-22 Sheldon Edward Emanuel Device for color projection of invisible rays
US2730566A (en) * 1949-12-27 1956-01-10 Bartow Beacons Inc Method and apparatus for x-ray fluoroscopy
US5033073A (en) * 1987-11-24 1991-07-16 Boeing Company System for radiograhically inspecting a relatively stationary object and related method

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