US2270373A - Neutron image converter - Google Patents
Neutron image converter Download PDFInfo
- Publication number
- US2270373A US2270373A US336311A US33631140A US2270373A US 2270373 A US2270373 A US 2270373A US 336311 A US336311 A US 336311A US 33631140 A US33631140 A US 33631140A US 2270373 A US2270373 A US 2270373A
- Authority
- US
- United States
- Prior art keywords
- neutrons
- layer
- neutron
- electrons
- reactive
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
- 239000010410 layer Substances 0.000 description 69
- 239000002245 particle Substances 0.000 description 22
- 230000005855 radiation Effects 0.000 description 16
- 239000000126 substance Substances 0.000 description 14
- 230000005684 electric field Effects 0.000 description 10
- 125000004429 atom Chemical group 0.000 description 8
- UIWYJDYFSGRHKR-UHFFFAOYSA-N gadolinium atom Chemical group [Gd] UIWYJDYFSGRHKR-UHFFFAOYSA-N 0.000 description 8
- 229910052688 Gadolinium Inorganic materials 0.000 description 6
- ZOXJGFHDIHLPTG-UHFFFAOYSA-N Boron Chemical compound [B] ZOXJGFHDIHLPTG-UHFFFAOYSA-N 0.000 description 3
- WHXSMMKQMYFTQS-UHFFFAOYSA-N Lithium Chemical compound [Li] WHXSMMKQMYFTQS-UHFFFAOYSA-N 0.000 description 3
- 125000004435 hydrogen atom Chemical class [H]* 0.000 description 3
- 229910052744 lithium Inorganic materials 0.000 description 3
- 238000004519 manufacturing process Methods 0.000 description 3
- FYYHWMGAXLPEAU-UHFFFAOYSA-N Magnesium Chemical compound [Mg] FYYHWMGAXLPEAU-UHFFFAOYSA-N 0.000 description 2
- 229910052770 Uranium Inorganic materials 0.000 description 2
- 238000010521 absorption reaction Methods 0.000 description 2
- 229910052790 beryllium Inorganic materials 0.000 description 2
- ATBAMAFKBVZNFJ-UHFFFAOYSA-N beryllium atom Chemical compound [Be] ATBAMAFKBVZNFJ-UHFFFAOYSA-N 0.000 description 2
- 229910052796 boron Inorganic materials 0.000 description 2
- 238000011835 investigation Methods 0.000 description 2
- 229910052749 magnesium Inorganic materials 0.000 description 2
- 239000011777 magnesium Substances 0.000 description 2
- 239000012048 reactive intermediate Substances 0.000 description 2
- JFALSRSLKYAFGM-UHFFFAOYSA-N uranium(0) Chemical compound [U] JFALSRSLKYAFGM-UHFFFAOYSA-N 0.000 description 2
- 230000001133 acceleration Effects 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 230000002349 favourable effect Effects 0.000 description 1
- 229910052739 hydrogen Inorganic materials 0.000 description 1
- 239000001257 hydrogen Substances 0.000 description 1
- 239000000543 intermediate Substances 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 238000000034 method Methods 0.000 description 1
- 230000003287 optical effect Effects 0.000 description 1
- 230000002285 radioactive effect Effects 0.000 description 1
- 238000000926 separation method Methods 0.000 description 1
- 239000002344 surface layer Substances 0.000 description 1
Images
Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
- H01J29/00—Details of cathode-ray tubes or of electron-beam tubes of the types covered by group H01J31/00
- H01J29/02—Electrodes; Screens; Mounting, supporting, spacing or insulating thereof
- H01J29/10—Screens on or from which an image or pattern is formed, picked up, converted or stored
- H01J29/36—Photoelectric screens; Charge-storage screens
- H01J29/38—Photoelectric screens; Charge-storage screens not using charge storage, e.g. photo-emissive screen, extended cathode
- H01J29/385—Photocathodes comprising a layer which modified the wave length of impinging radiation
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
- H01J31/00—Cathode ray tubes; Electron beam tubes
- H01J31/08—Cathode ray tubes; Electron beam tubes having a screen on or from which an image or pattern is formed, picked up, converted, or stored
- H01J31/50—Image-conversion or image-amplification tubes, i.e. having optical, X-ray, or analogous input, and optical output
- H01J31/501—Image-conversion or image-amplification tubes, i.e. having optical, X-ray, or analogous input, and optical output with an electrostatic electron optic system
Definitions
- This invention relates to devices for producing images with the aid of neutrons as depicting radiation, and is more particularly concerned with a neutron image converter as more specifically described hereinafter.
- This and other inventive objects are attainedby a device comprising, in combination, a vacuum tube, which contains a neutron reactive intermediate layer, from a surface of which slow electrons are liberated, an accelerating electricfield, an electron-optical depicting system and fluorescent screen or a photographic plate.
- a device comprising, in combination, a vacuum tube, which contains a neutron reactive intermediate layer, from a surface of which slow electrons are liberated, an accelerating electricfield, an electron-optical depicting system and fluorescent screen or a photographic plate.
- the image produced by the accelerated electrons is, if the accelerating fields are properly chosen, considerably richer in contrasts and more intense than the image obtained with the formerly proposed method.
- the material to be used for the neutron-reactive layer may be lithium or boron or a substance containing atoms of the one or the other of said elements. In connection therewith it is desirable to choose the distribution of the isotopes in such a manner that the sort of isotope active in the neutron-converting reaction is enriched relative to the natural distribution of the isotopes of the respective element.
- the neutron-reactive layer may, however, also consist of uranium or of atoms thereof. The neutrons liberate from these latter heavy particles particularly rich in energy and excellently suited for the production of slow electrons.
- the neutron-reactive layer may, under circumstance, especially if quick neutrons are used as depicting radiation, be formed advantageously by a layerloaded with hydrogen, this layer emitting slow electrons under the action of the recoil protons energized by the quick neutrons.
- quick neutrons or rapid neutrons are meant neutrons whose wavelengths are longer than the diameter of the bombarded atom nucleus: with the atoms concerned, this requirement is met by neutrons with speeds corresponding to a few hundred thousand volts energy.
- recoil protons are meant protons formed by repulsion. In the present; connection it is noted that the recoil protons are given an acceleration due to impact by the impinging neutrons, so that they move with a speed corresponding to the absorbed energy.
- the neutron-reactive layer or the layer adja-- cent to it may also contain beryllium or magnesium or atoms of these substances to increase the production of slow electrons under the action of the heavy charged particles or of the quick electrons liberated by the neutrons out of the neutron-reactive layer.
- the image on the fluorescent screen may be subsequently intensified either only once or several times by means of an electron-optical image amplifier.
- reflecting layer may be provided between the neutronreactive layer and the fluorescent substance. This layer reflects the radiation emitted by the fluorescent mass towards the side of the neutronreactive layer back to the photosensitive layer.
- the reflecting layer must be chosen such that it permits the heavy charged particles or electrons liberated by the neutrons to pass through it unimpededly.
- the electrons liberated by the neutrons have an energy of about 70,000 volts. These electrons when passing through the surface of the neutron-reactive layer or of an adjacent layer generate slow electrons which are employed for producing an image in the above described way.
- Figure 1 shown an axial section through a device designed according to this invention
- Figure 2 shows a modified concharged particles or electrons is diiferent from place to place and corresponds to the intensity ofthe radiation of neutrons as it is transmitted by the object or body to be depicted.
- the heavy charged particles or electrons liberate slow electrons either from the neutron-reactive layer 5 itself or from a layer 6 located adjacent thereto, which electrons are emitted into the vacuum space I and are there accelerated, for instance by an electric field V1 existing between the electrode 8, or the layer 5, or 6 respectively.
- an electron-optical depicting system consisting, for instance, of said accelerating electric fleld and 01' an additional magnetic or electrostatic lens 9 said slow electrons are gathered upon a fluorescent screen or upon a photographic layer It], where they form an image, which shows a representation, rich in contrasts, of the object or body 3, as it depends on the absorption relations for neutrons in the object or body undergoing investigation.
- Fig. 1 Another device intended to increase the intensity and the contrast, in case the layer l should constitute a fluorescent screen.
- the radiation proceeding from this screen acts upon the adjacent layeril which is sensitive to light and emits photo-electrons under the action of light which photo-electrons are accelerated by the electric field V3 existing between the layer II and the electrode I2 and collected upon the fluorescent screen I by means of an electronoptical depicting system, for instance a magnetic cent screen ll can again be amplified in intensity by a second image-amplifier.
- a magnetic cent screen ll can again be amplified in intensity by a second image-amplifier.
- the device has been designed such that the heavy charged particles or electrons liberated from the neutron-reactive layer by the neutrons act upon an adjacent fluorescent mass [8, the radiation of which liberates slow electrons from a layer l9 sensitive to light, as is illustrated in Fig. 2, it is desirable to provide likewise a reflecting layer 20 between the neutron-reactive layer 5 and the fluorescent substance ll. 1
- a filter 22 capable of absorbing the X-rays, for instance a filter of lead, which is permeable to neutrons.
- the images obtained with the present improved device can be made considerably sharper than the images produced with the aid of the former devices, because the slow electrons utilized for making the images proceed only from an extraordinarily thin surface layer of the neutron-reactive layer 5, or of the special layer 6 delivering the slow electrons.
- the energy of the electrons emitted from the layer containing gadolinium is comparatively large, it is advantageous to utilize them not di-' rectly for the liberation of slow electrons from the neutron-reactive layer itself or from an adjacent layer, but to cause them to act upon a fluorescent mass which is either mixed with the substance of the neutron-reactive layer or is provided in its proximity.
- the radiation emitted by the fluorescent mass under the action of the electrons is employed for the liberation of slow electrons out of an adjacent layer, which electrons are used for the production of the image.
- neutron-reactive layer consisting of gadolinium or containing gadoiinium atoms is that it reacts practically only with neutrons of terminal energy (that is to say.
- the gadolinium-containing neutron-reactive layer dlflers in this respect advantageously for instance from neutron-reactive layers containing lithium or boron atoms.
- This property is especially favorable in the case that, as is the rule, the source of neutrons emits neutrons of unhomogeneous energy so that there are, besides the neutrons of thermal energy, also neutrons with a considerably larger energy which are absorbed by the bodies under investigation olinium it is suitable to choose the thickness of the neutron-reactive layer nearly equal to the range of the electrons liberated from that substance, because no electrons reach the surface of the neutron-reactive layer (and pass from the latter into the image converter) from those parts of the layer which are farther away from the surface thereof than the width of range of the electrons. If, on the other hand, the neutron-reactive layer containing gadolinium is too thin, the output is reduced, as a part of the neutrons passes through such a thin layer without being caught
- a device for producing images with the aid of neutrons as depicting radiation comprising a vacuum tube containing a neutron-reactive layer in which charged particles are generated by impinging neutrons, an electric field and an electron-optical depicting system for accelerating slow electrons dissolved by said charged particles, and an electron-sensitive system on which said slow electrons after having been accelerated are collected to form an image which shows a representation of the intensity of the incoming beam of neutrons.
- a device for producing images with the aid of neutrons as depicting radiation comprising a vacuum tube containing a neutron-reactive layer in which charged particles are generated by impinging neutrons, another layer adjacent to the neutron-reactive layer from which second named layer said charged particles dissolve slow electrons, an electric field and an electron-optical depicting system for accelerating said slow electrons, and an electron-sensitive system on which said slow electrons after having been accelerated are collected to form an image which shows a representation of the intensity of the incoming beam of neutrons.
- a device as defined in claim 5 in which the layer from which the slow electrons are liberated contains atom selected from the group consisting of beryllium and magnesium.
- a device for producing images with the aid of neutrons as depicting radiation comprising a vacuum tube containing a neutron-reactive lay-- er in which charged particles are generated by impinging neutrons, an electric field and an electron-optical depicting system for accelerating slow electrons dissolved by said charged particles, a fluorescent substance on which said slow electrons after having been accelerated are collected to form an image, and a photographic layer adjacent to said fluorescent substance on which the radiation excited in the fluorescent substance produces a photographic representation of the intensity of the incoming beam of neutrons.
- a device for producing images with the aid of neutrons as depicting radiation comprising a vacuum tube containing a neutron-reactive layer in which charged particles are generated by impinging neutrons, an electric field and an electron-optical depicting system for accelerating slow electrons dissolved by said charged particles, at fluorescent substance on which said slow electrons after having been accelerated are collected to form an image, and a second image-amplifier which amplifies the intensity of said image.
- a device for producing images with the aid of neutrons as depicting radiation comprising a vacuum tube containing a neutron-reactive layer in which charged particles are generated by impinging neutrons, a fluorescent substance adjacent to said neutron-reactive layer, a photosensitive layer from which radiation excited in said fluorescent substance by said charged particles dissolves slow electrons, an electric field and an electron-optical depicting system for accelerating said slow electrons, and an electron-sensitive system on which said slow electrons after having been accelerated are collected to form an image which shows a representation of the intensity of the incoming beam of neutrons.
- Adevice as defined in claim 9 in which a reflecting layer permeable by the charged particles generated by the neutrons is inserted between the neutron-reactive layer and said fluorescent substance,
- a device for producing images with the aid of neutrons as depicting radiation comprising a vacuum tube containing a layer containing hydrogen atoms which are energized to high speed by impinging neutrons by collision, an electric field and an electron-optical depicting system for accelerating slow electrons dissolved by said high speed hydrogen atoms, and an electronsensitive system on which said slow electrons after having been accelerated are collected to form an image which shows a representation of the intensity of the incoming beam of neutrons.
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
DEL98304D DE757713C (de) | 1939-06-25 | 1939-06-25 | Einrichtung zur Erzeugung sichtbarer oder photographischer Bilder von Koerpern unterVerwendung einer Neutronenstrahlenquelle |
Publications (1)
Publication Number | Publication Date |
---|---|
US2270373A true US2270373A (en) | 1942-01-20 |
Family
ID=34071526
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US336311A Expired - Lifetime US2270373A (en) | 1939-06-25 | 1940-05-20 | Neutron image converter |
Country Status (3)
Country | Link |
---|---|
US (1) | US2270373A (de) |
DE (1) | DE757713C (de) |
FR (1) | FR886565A (de) |
Cited By (23)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2527913A (en) * | 1947-08-06 | 1950-10-31 | Radio Industrie Sa | Photoelectric device |
US2555423A (en) * | 1947-04-16 | 1951-06-05 | Sheldon Edward Emanuel | Image intensifying tube |
US2605335A (en) * | 1949-05-25 | 1952-07-29 | Gen Precision Lab Inc | Light amplifier |
US2612610A (en) * | 1948-11-06 | 1952-09-30 | Westinghouse Electric Corp | Radiation detector |
US2690516A (en) * | 1948-03-09 | 1954-09-28 | Shcldon Edward Emanuel | Method and device for producing neutron images |
US2717971A (en) * | 1949-03-30 | 1955-09-13 | Sheldon Edward Emanuel | Device for storage of images of invisible radiation |
US2730644A (en) * | 1951-04-10 | 1956-01-10 | Hyman A Michlin | Electroluminescent light means |
US2747131A (en) * | 1951-10-12 | 1956-05-22 | Sheldon Edward Emanuel | Electronic system sensitive to invisible images |
US2767324A (en) * | 1953-06-26 | 1956-10-16 | High Voltage Engineering Corp | Apparatus for neutron detection |
US2774901A (en) * | 1947-07-08 | 1956-12-18 | Sheldon Edward Emanuel | Tube for electro-magnetic images |
US2782332A (en) * | 1949-04-06 | 1957-02-19 | Sheldon Edward Emanuel | Method and device for reading images of invisible radiation |
US2802963A (en) * | 1952-02-28 | 1957-08-13 | Sheldon Edward Emanuel | Tube for reproducing invisible images |
US2802962A (en) * | 1951-06-01 | 1957-08-13 | Sheldon Edward Emanuel | Neutron storage tube |
US2804561A (en) * | 1948-03-09 | 1957-08-27 | Sheldon Edward Emanuel | X-ray camera |
US2804560A (en) * | 1951-06-01 | 1957-08-27 | Sheldon Edward Emanuel | Electronic device sensitive to invisible images |
US2842695A (en) * | 1954-05-17 | 1958-07-08 | Schlumberger Well Surv Corp | Radiation-responsive apparatus |
US2994773A (en) * | 1956-02-20 | 1961-08-01 | Westinghouse Electric Corp | Radiation detector |
US3004101A (en) * | 1956-04-09 | 1961-10-10 | Gen Electric | Color radiography |
US3461332A (en) * | 1965-11-26 | 1969-08-12 | Edward E Sheldon | Vacuum tubes with a curved electron image intensifying device |
US3875440A (en) * | 1971-11-24 | 1975-04-01 | Electron Physics Ltd | Cascade image intensifier tube with independently sealed sections |
US4929867A (en) * | 1988-06-03 | 1990-05-29 | Varian Associates, Inc. | Two stage light converting vacuum tube |
US5406086A (en) * | 1993-04-13 | 1995-04-11 | Commissariat A L'energie Atomique | Particle dose rate meter |
US6037597A (en) * | 1997-02-18 | 2000-03-14 | Neutech Systems, Inc. | Non-destructive detection systems and methods |
Families Citing this family (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE1041184B (de) * | 1955-09-12 | 1958-10-16 | Gen Electric | Schirm fuer Roentgenstrahldurchleuchtung mit einer fuer Roentgenstrahlen empfindlichen, sichtbares Licht emittierenden Schicht und einer dieses sichtbare Licht verstaerkenden Zelle |
DE1189215B (de) * | 1961-05-06 | 1965-03-18 | Telefunken Patent | Mit freien Elektronen arbeitende Bildwandler- oder Bildverstaerkerroehre |
-
1939
- 1939-06-25 DE DEL98304D patent/DE757713C/de not_active Expired
-
1940
- 1940-05-20 US US336311A patent/US2270373A/en not_active Expired - Lifetime
-
1942
- 1942-10-05 FR FR886565D patent/FR886565A/fr not_active Expired
Cited By (23)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2555423A (en) * | 1947-04-16 | 1951-06-05 | Sheldon Edward Emanuel | Image intensifying tube |
US2774901A (en) * | 1947-07-08 | 1956-12-18 | Sheldon Edward Emanuel | Tube for electro-magnetic images |
US2527913A (en) * | 1947-08-06 | 1950-10-31 | Radio Industrie Sa | Photoelectric device |
US2804561A (en) * | 1948-03-09 | 1957-08-27 | Sheldon Edward Emanuel | X-ray camera |
US2690516A (en) * | 1948-03-09 | 1954-09-28 | Shcldon Edward Emanuel | Method and device for producing neutron images |
US2612610A (en) * | 1948-11-06 | 1952-09-30 | Westinghouse Electric Corp | Radiation detector |
US2717971A (en) * | 1949-03-30 | 1955-09-13 | Sheldon Edward Emanuel | Device for storage of images of invisible radiation |
US2782332A (en) * | 1949-04-06 | 1957-02-19 | Sheldon Edward Emanuel | Method and device for reading images of invisible radiation |
US2605335A (en) * | 1949-05-25 | 1952-07-29 | Gen Precision Lab Inc | Light amplifier |
US2730644A (en) * | 1951-04-10 | 1956-01-10 | Hyman A Michlin | Electroluminescent light means |
US2804560A (en) * | 1951-06-01 | 1957-08-27 | Sheldon Edward Emanuel | Electronic device sensitive to invisible images |
US2802962A (en) * | 1951-06-01 | 1957-08-13 | Sheldon Edward Emanuel | Neutron storage tube |
US2747131A (en) * | 1951-10-12 | 1956-05-22 | Sheldon Edward Emanuel | Electronic system sensitive to invisible images |
US2802963A (en) * | 1952-02-28 | 1957-08-13 | Sheldon Edward Emanuel | Tube for reproducing invisible images |
US2767324A (en) * | 1953-06-26 | 1956-10-16 | High Voltage Engineering Corp | Apparatus for neutron detection |
US2842695A (en) * | 1954-05-17 | 1958-07-08 | Schlumberger Well Surv Corp | Radiation-responsive apparatus |
US2994773A (en) * | 1956-02-20 | 1961-08-01 | Westinghouse Electric Corp | Radiation detector |
US3004101A (en) * | 1956-04-09 | 1961-10-10 | Gen Electric | Color radiography |
US3461332A (en) * | 1965-11-26 | 1969-08-12 | Edward E Sheldon | Vacuum tubes with a curved electron image intensifying device |
US3875440A (en) * | 1971-11-24 | 1975-04-01 | Electron Physics Ltd | Cascade image intensifier tube with independently sealed sections |
US4929867A (en) * | 1988-06-03 | 1990-05-29 | Varian Associates, Inc. | Two stage light converting vacuum tube |
US5406086A (en) * | 1993-04-13 | 1995-04-11 | Commissariat A L'energie Atomique | Particle dose rate meter |
US6037597A (en) * | 1997-02-18 | 2000-03-14 | Neutech Systems, Inc. | Non-destructive detection systems and methods |
Also Published As
Publication number | Publication date |
---|---|
FR886565A (fr) | 1943-10-19 |
DE757713C (de) | 1953-09-07 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US2270373A (en) | Neutron image converter | |
Anderson | The positive electron | |
Bardin et al. | A search for the double beta decay of 48Ca and lepton conservation | |
Stebbings et al. | Collisions of Electrons with Hydrogen Atoms. V. Excitation of Metastable 2 S Hydrogen Atoms | |
Fabre et al. | Angular distribution in above-threshold ionisation of xe at 0.53 μm | |
Martin | AN INVESTIGATION OF THE BETA-RADIATION AND GAMMA-RADIATION EMITTED IN THEDECAYS OF SEVERAL SHORT-LIVED NEUTRON-INDUCED RADIOACTIVITIES | |
Dempster | The properties of slow canal rays | |
Aschenbrenner | Low-Energy Protons from Targets Bombarded by 15-Mev Deuterons | |
GB1028834A (en) | Device for triggering a gas detector of nuclear particles, x-ray photons or gamma-ray photons | |
US2279023A (en) | Method and device for depicting objects | |
Duncanson et al. | Artificial disintegration by radium C'α-particles-aluminium and magnesium | |
Powell et al. | A New Method for the Determination of the Mass of Mesons | |
Malmskog et al. | On the low-energy band structure in 187Os | |
Aebersold | The cyclotron: a nuclear transformer | |
Aston | Isotopic Constitution of Lead from Different Sources | |
US2453163A (en) | X-ray apparatus and procedure | |
Iliffe | An introduction to nuclear reactor theory | |
Brolley Jr et al. | A Search for Short Period Activities from U 235 Fission Products | |
Goldschmidt-Clermont et al. | On the Measurement of the mass of cosmic ray particles using a sandwich of photographic plates in a magnetic field | |
JPH05333158A (ja) | 放射線検出装置 | |
Heitler et al. | The study of atomic processes with the photographic plate | |
Taylor et al. | RESONANCE CAPTURE OF PROTONS BY Mg $ sup 2$$ sup 5$ | |
Müller-Gatermann | Nuclear structure of neutron-deficient nuclei in the mass region A 180 | |
Morton | Nuclear radiation detectors | |
Jones et al. | The Luminescent Chamber and other new Detectors |