Usage: to generate x-ray radiation. Essence: is that the x-ray tube includes a vacuum envelope with the outlet box placed in the recess in the form of glass made in the side wall of the shell, inside which is placed the source of electrons is the cathode, a focusing system and a reflective target, the metal which is deposited on a substrate is the anode. The latter has a radial groove not reaching the continuation of the centerline of the electron beam (coincident with the longitudinal axis of the tube), and the edge surface of the reflective target is adjacent to the edge of the recess in the anode. The proposed implementation allows to obtain a small distance between the focal spot and the surface of the exit window and use the tube together with short-focus x-ray lens. This ensures the preservation of power, characteristic of the tube with a reflective anode. Effect: provision of small distances between the focal spot of the reflective target and the surface of the exit window without reducing the capacity of the tube. 1 C.p. f-crystals, 2 Il.
The invention relates to x-ray techniques, and more particularly to means for generating a roentgen(Rechentechnik. The Handbook. Book 1. - M.: Mashinostroenie, 1992, S. 90-121 ), containing the vacuum envelope, a source of electrons, a focusing electron optical system, a target for receiving x-ray radiation and outlet box. The target is a layer of metal (cu, Ag, Mo, W, etc.) deposited on a solid substrate, having forced liquid or gas cooling. The target is oriented so that the plane of the surface of the target was some angle with the axis of the electron beam from the side of the exit window. Outlet box is made of metal with a small atomic number and fixed in the sheath tube in the area of the anode.
The disadvantage of this design is a significant distance from the focal spot to the surface of the exit window. This leads, in particular, to the inability to use, the tube together with short-focus x-ray lens.
Closest to the present invention is the design of the x-ray tube described in U.S. patent No. 6 282 263 (publ. 28.08.01) . X-ray tube according to the patent  contains the vacuum shell with the outlet box. Inside the vacuum shell is placed a source of electrons, a focusing system and a reflective target located at the end of the heat sink p is prevalent in the form of a radiolucent tubular element, part of the side wall of the vacuum casing and surrounding the reflective target.
This x-ray tube is specifically designed to lead to the window outside was close to summarize the input device for focusing x-rays. In one best described in the patent  examples when using a reflective target, the distance from the focal spot to the outer surface of the exit window is 7 mm
This distance is not always acceptable when using the x-ray tube together with short-focus x-ray lens. However, the possibility of reducing it to a known structure according to the patent  is limited due to the fact that the outlet box is located in the side wall of the vacuum casing tube, which is located inside the target, which is placed on the heat sink substrate. Therefore, the outlet box may not be from the focal spot at a distance less than the radius of the heat sink substrate placed on her target. Reduction of the radius of the substrate with a target closer to the center of the part of the vacuum envelope, which is the output window in the form of a tubular element, would entail a decrease in mechanical strength E from the target and reducing power tubes.
The present invention aims to obtain a technical result, which is to offer small distance between the focal spot of the reflective target and the surface of the exit window without reducing the capacity of the tube.
To achieve this, the technical result of the proposed x-ray tube as mentioned above is known, is closest to it, contains the vacuum shell with the outlet box, made in its side surface, and placed inside the vacuum shell electron source, a focusing system and cooling the substrate with the target located at the end of the heat sink substrate facing the electron source.
In contrast to the known x-ray tube, the proposed x-ray tube facing the electron source end heat sink substrate has a radial recess, not reaching the continuation of the centerline of the electron beam. Outlet box placed in the cavity, which is made in the side wall of the vacuum casing and includes its more remote from the electron source part specified in the hollow heat sink substrate. To the edge of this recess is adjacent the edge surface of the target.
Describes how to perform pozemky to heat the substrate, is close to the axial line of the electron beam, the distance from the center of the focal spot to the output window commensurate with the radius of the electron beam and does not depend on the size of the heat sink substrate and the target.
It is preferable for this embodiment of the recess in the heat sink substrate, when she has a flat section that is tangent to the continuation of the electron beam, and thus the output window parallel to the specified plane area of the recess in the heat sink substrate and the target surface is inclined in the direction of the exit window.
This can be achieved the greatest approximation of the output window to the center of the focal spot.
The invention in one possible specific variants of its execution illustrated by drawings:
in Fig.1 shows the x-ray tube in section;
in Fig.2 on a larger scale showing part of the recess in the side surface of the vacuum shell, the recess in the heat sink substrate and the target with the incident electron beam.
X-ray tube (Fig.1) contains the vacuum shell 1, the source of electrons is the cathode 2, the focusing electrode 3, the diaphragm 4 and the heat sink substrate - massive anode 5 coated with a metal target 6. In the sides of the Noi to the longitudinal axis 8 of the tube, posted by outlet box 9. The output window does not reach the continuation of the centerline of the electron beam, matching shown in Fig.1 with the longitudinal axis 8 of the tube, about the size of the radius r of the electron beam. The anode 5 is made with a radial recess 10 (Fig.1 shows a dashed line) in its end portion facing the cathode 2. The side surface of the recess 10 are similar to the half. In this radial recess is more remote from the cathode 2 half Cup 7 (right in Fig.1). The anode 5 may be forced liquid or air cooled (cooling means not shown).
The recess in the vacuum casing 1 in the form of glass 7 is designed to accommodate short-focus x-ray lens (or part of such lenses adjacent to its input end) or small objects to be irradiated.
In the form shown in Fig.1 (and in larger scale in Fig.2) embodiment, the tube radial recess 10 in the anode 5 has a flat portion 11. This section of the tangent to the continuation of the beam 13 of the electrons, i.e. the continuation of the generatrix 12 of the electron beam, closest to the pin box 9, lies in the plane of the section 11. The edge 14 of the reflective surface of the target adjacent to the edge Wielkie from the axis of the electron beam (the same shown on the drawings with the longitudinal axis 8 of the tube at some distance, approximately equal to the radius r of the beam, or that the same is the radius of the focal spot. Due to this, the beam 13 electrons completely hits the target 6 and are not inhibited by lead in box 9. The reflective surface of the target 6 and the end surface of the anode 5 (left in Fig.1), which is applied to the target, which is inclined towards the outlet box 9, i.e., the form with the plane of the exit window is an acute angle. This orientation of the reflective surface of the target improves the conditions of withdrawal of the stimulated emission from the focal spot through the window 9.
From what was said above about the mutual position of the exit window 9, the notches 10 and the target 6 shows that further reduction of the distance between the outlet box and the focal spot on the target is impossible. In fact, this distance becomes close to the distance, characteristic x-ray tube with target "through" type and does not depend on the sizes of the anode and the target.
The electron beam in the described x-ray tube may have a cross-section not only a circular shape, but the shape of an elongated rectangle and shape on the target so-called linear focus. In this case, the minimum distance from the geometric center of the focal spot to the output window 9 occurs when the PR is pendicular to the plane of the drawing.
The proposed x-ray tube operates as follows. When the supply voltage in the area of the cathode 2 through the focusing electrode 3 is formed by converging the electron beam, which is accelerated in the direction of the diaphragm 4, is an equipotential space and inhibited in the target 6 inducyruya x-rays. Part of this radiation exits through the exit window 9 and may be collected by the x-ray lens located in the cavity of the Cup 7 or influence the irradiated object is placed in this cavity.
In the case of the proposed technical solutions in the design of x-ray tubes, high power (1 kW or more) outlet box can be moved away from the plane of the recess at a distance of about 0.2-1 mm in order to provide thermal isolation from the anode.
In really tested the tubes with a capacity of 50 watts and above the plane 11 of the recess 10 has not reached the axis of the electron beam 13 at a distance of less than 0.3 mm, the minimum distance from this plane to the inner surface of the exit window was 0.2 mm, and the angle of its inclination relative to the longitudinal axis of the tube 2.
Thus, the technical solution according to the invention allows the POPs who inim spot and the inner surface of the exit window.
Sources of information
1. Rechentechnik. The Handbook. Book 1. M: mechanical engineering, 1992, S. 90-121.
2. U.S. patent No. 6282263, publ. 28.08.01.
1. X-ray tube containing a vacuum envelope with the outlet box, made in its side wall, and placed inside the vacuum shell electron source, a focusing system and a reflective target from the heat sink substrate, characterized in that facing the electron source end heat sink substrate has a radial recess, not reaching the continuation of the centerline of the electron beam, the exit window is placed in the cavity, which is made in the side wall of the vacuum casing and includes its more remote from the electron source part specified in the hollow heat sink substrate, and the edge surface of the reflective target is adjacent to the edge of this recess.
2. X-ray tube under item 1, characterized in that the radial recess in the heat sink substrate has a flat section that is tangent to the continuation of the electron beam, the exit window parallel to the specified plane area of the radial grooves in the heat sink substrate and the surface of the reflective target is tilted in the direction of the exit window.
FIELD: flaw inspections, customs examination equipment, medicine, and roentgen diagnosing spectroscopic installations.
SUBSTANCE: proposed X-ray tube has vacuum envelope accommodating anode, X-ray output aperture, cathode assembly incorporating field-radiating cathode in the form of bundle of carbon fibers placed in conducting or semiconducting shell, contact assembly of field-radiating cathode, and cap that functions as control electrode. In order to prevent stray surface electric conductance caused by sputtering of field-radiating cathode material on structural components of X-ray tube, dielectric washer is inserted in this tube wherein during X-ray tube assembly annular cavity is formed between inner hole of washer, field-radiating cathode shell, and upper end of field-radiating cathode contact assembly. Cavity provided in dielectric washer and also its slots prevent formation of solid conducting and semiconducting films which enhances stability of electrical and radiating characteristics of tube. For raising electric strength of tube and excluding breakdown of its envelope cap is installed on dielectric washer that functions as control electrode. Cap is installed so that axis of carbon fiber bundle is aligned with that of optoelectronic system of X-ray tube and symmetry axis of cap.
EFFECT: enhanced operating stability, electric strength, reliability, and service life of X-ray tubes with field-radiating cathode.
1 cl, 3 dwg
FIELD: roentgen engineering; producing roentgenograms, for instance in medicine.
SUBSTANCE: proposed X-ray source module has X-ray tube incorporating body, cathode and anode assemblies, as well as generator unit incorporating high-rating voltage divider whose high-voltage lead is connected to one of tube assemblies; X-ray tube body is made in the form of metal cylinder accommodating sectionalized cylindrical high-voltage insulator. One of its ends is connected through vacuum-tight joint to one of body ends and other end mounts cathode assembly. Anode assembly is disposed on other end of body and is made in the form of anode tube brought outside the body that carries target on its loose end. Generator unit is disposed inside cylindrical high-voltage insulator whose inner space is filled with oil. Side surface of insulator functions as high-rating voltage divider.
EFFECT: reduced mass and size of module.
1 cl, 1 dwg
FIELD: roentgen engineering, in particular, engineering of x-ray emitters, possible use in high energy industrial x-ray devices, and also in customs browsing complexes.
SUBSTANCE: x-ray emitter contains, positioned coaxially, vacuumized semi-wave coaxial resonator, tetrode cannon with radial anode, connection element of generator with resonator in form of anchor ring shaped head and a target. First and second hollow internal semiconductors of resonator are positioned coaxially and separated from each other by high frequency gap. In first internal conductor on the side of its free end injector of electrons is positioned, cathode of which is directed towards the target. Base of second internal conductor is connected to first end wall of resonator. Tetrode cannon and radial anode are positioned between first internal conductor and second end wall of resonator. First internal conductor is connected to radial anode and rigidly connected to external conductor of resonator by means of supporting dielectric isolator positioned between them. The target is positioned in the hollow of second internal conductor or in vacuumized hollow of span tube, positioned outside the resonator coaxially to second internal conductor.
EFFECT: generation of high energy (over 400 keV) flow of electrons with efficiency not less than 30% at working frequency ≈ 300 MHz, increased electric durability, reliability and lifetime.
8 cl, 5 dwg
FIELD: physics; X-ray inspection.
SUBSTANCE: X-ray generator includes high DC voltage generator, X-ray tube in the form of a metallic enclosure, anode assembly with a target anode and window for the X-ray radiation output, cathode assembly in the form of a cathode with a filament and a cathode insulator, cathode filament power supply unit; the high DC voltage generator and the cathode filament power supply unit are located in the internal cavity of the cathode insulator, filled with dielectric material.
EFFECT: decrease in dimensions and weight and increase in reliability of device as whole.
2 cl, 1 dwg
FIELD: sources of X-ray radiation.
SUBSTANCE: X-ray tube of permanent radiation, consists of cylindrical anode, annular cathode, which consists of several glow threads, focusing electrode, windows for withdrawal of X-ray radiation and leak-tight casing. Annular cathode, which consists of two and more glow threads, is isolated from tube casing and focusing electrode, which allows to change size of focal spot by means of control voltage supply on cathode in regard to casing and focusing electrode. Anode is made in the form of massive copper cylinder, to the end of which target is fixed by means of soldering or welding, made of material that is necessary for generation of corresponding X-ray radiation. Focusing electrode is installed so that products of cathode evaporation would not get to anode end surface. Internal part of tube casing is additional element of focusing, configuration of internal surface of tube casing that faces cathode and focusing electrode is designed to provide focusing of electrons on anode surface. Output collimator is added in tube design, and its dimensions are selected so that cathode evaporation products would not get on the surface of output window.
EFFECT: simplification of design, reduction of dimensions, increase of tube operation resource, possibility of focal spot regulation by means of cathode potential change in regard to focusing electrode.
SUBSTANCE: method of making a through-type target of pulse-type X-ray tube involves using metal foil made from a high-atomic number metal. Elements are made on the surface of the foil, which can be stretched or compressed due to flexural deformation of the foil. In the target of the X-ray tube made of high-atomic number metal foil on the area of the surface of the foil lying in the zone of the focal spot, there are drop-forged protrusions, the height and maximum dimension in the cross-section of which do not exceed 0.2S and 0.3d, respectively, where S is the size of the gap between the cathode and the target, d is the diameter of the focal spot of the tube, wherein the distance between protrusions does not exceed 0.3d or the foil is divided into corrugated strips mounted on a substrate made from low-atomic number material; strips in the plane of the substrate lie tightly against each other; the height and spacing of the corrugations do not exceed 0.2S and 0.2d, respectively, where S is the size of the gap between the cathode and the target, d is the diameter of the focal spot of the tube; the width of the strips does not exceed 2 mm.
EFFECT: reduced mechanical stress in the material of the target.
3 cl, 4 dwg, 4 dwg
SUBSTANCE: plasma generator of deceleration radiation has a microwave resonator placed in a magnetostatic field with a plug configuration with a small plug ratio and excited by a microwave generator. Pulse-forming magnetic coils are placed on the microwave resonator in the interpole space of an electromagnet; the resonator is connected to a pulse gas valve which enables to form a powerful gas jet directed into the region of generating a bunch of accelerated electrons. A solid-state target is placed in the resonator outside the heating zone.
EFFECT: high radiation intensity, clear radiation pattern, which widens the spectral range of radiation in the region of hard X-rays.
SUBSTANCE: in device and method for generation of emission from discharge plasma there performed is laser-induced discharge between the first and the second electrodes with energy input of pulse power source to discharge plasma and generation from discharge plasma of emission together with by-product in the form of neutral and charged debris. Based on selection of irradiation point of electrode with laser beam, geometry of electrodes and discharge outline, there formed is asymmetric discharge of mainly bent/banana shape, the own magnetic field of which has gradient immediately near discharge, which determines direction of predominant movement of discharge plasma flow from electrodes to area of less strong magnetic field.
EFFECT: increasing optic emission beam power.
8 cl, 4 dwg
SUBSTANCE: portable X-ray system (200) has sensing means for detecting whether an anti-scatter grid (230) is attached to a portable detector (240) or not. The system is able to automatically change the default exposure settings (265a, 265b, 265c, 265d), when the grid (230) is removed or attached to the portable detector (240).
EFFECT: reducing the risk of under- or over-exposure of the image.
16 cl, 2 dwg
SUBSTANCE: X-ray tube with modulated radiation has a vacuum envelope with an output window which is transparent for X-ray radiation and, inside the vacuum envelope, an electron source, an electron focusing system and an anode whose surface is coated with a layer of the target metal. The electron source used in the disclosed invention is a microchannel plate at the input of which UV radiation of a semiconductor photodiode or laser is transmitted.
EFFECT: enabling modulation of radiation of an X-ray tube.