RU2288466C1 - Device for carrying out radiographic and tomographic examination - Google Patents

Abstract

FIELD: quality control engineering.

SUBSTANCE: device has transportation channels being optical fiber scintillators composed from fiber filaments scintillating in various optical spectrum zones. The fibers are collected into truncated cone or truncated pyramid package. Means for placing sample under study is reciprocally movable or rotatable. Means for recording radiation has deflecting mirror and at least two optical channels manufactured as input projection objective having filter, image amplifier, zooming objective and charge-bound matrix.

EFFECT: enhanced effectiveness and high spatial resolution not only in parallel but in conical beam as well; wide range of functional applications in registering various types of penetrating radiation.

3 cl, 3 dwg

Description

The invention relates to the study of the internal structure of objects, namely to the analysis of objects by radiation methods, for example using neutron, x-ray or gamma radiation.

Known devices for radiography and tomography of the internal structure of objects in which the studied object is illuminated by a diverging x-ray beam and a shadow image of the internal structure of the object under study is obtained on the corresponding display system.

Klyuev V.V. et al. Industrial radiation introscopy. M. Energoatomizdat, 1985, p. 5-8.

The disadvantage of these devices using a diverging beam is low sensitivity to small-sized details of the internal structure of the object (defects, inclusions).

A well-known technical solution is a device for studying the internal structure of objects, for obtaining shadow projections of the cross sections of the studied object by scanning it with a collimated x-ray beam, detecting the radiation transmitted through the object by a detector.

UK patent No. 1283915, IPC: G 01 N 23/08, 1975

In this device, the obtained spatial resolution in shadow projections is determined by the dimensions of the collimated beam and / or detector in the scanning direction, i.e. if there are small details of the structure in the studied object, the latter may not be detected in the resulting shadow projection.

A disadvantage of the known technical solutions is the movement to obtain shadow images of precisely collimated beams relative to the object.

This leads to a complication of the overall design, to increased requirements for radiation protection, to the possibility of gaps in the control of the object due to sudden movements of the emitter, as well as low efficiency of the use of radiation from the source, increased study time and the very need for collimating the beam.

A device for small angle tomography is known, which contains a source of penetrating radiation, a collimator that generates a radiation flux incident on the object in the form of low-diverging beams, means for moving the object relative to the radiation incident on it, a spatial filter, and a detector.

Patent of the Russian Federation No. 2119659, IPC: G 01 N 23/02, 1998. The device has a complex kinematic structure for identifying a diverging beam after the object under study.

A device for radiography and tomography containing a source of penetrating radiation, a means of moving the studied object, an optical radiation registration system containing a scintillation screen, a flat mirror, a lens, a photodetector (TV camera) and a correction lens.

Patent of the Russian Federation No. 2189031, IPC: G 01 N 23/04, 2002. The device has a sophisticated optical imaging system, relatively low image clarity and sensitivity.

A device for detecting contraband is known, comprising a polyenergy source of γ radiation, a spectrometric γ radiation detector, a detector signal amplifier, an amplitude-digital converter, a controller and a pulse intensity comparator in selected energy regions (a pulse selector for reflected γ radiation) and a display.

Patent of the Russian Federation No. 2161299, IPC: G 01 N 23/08, 2000

The device, responding to the presence of attached mass (smuggling) behind the screen, does not allow one to judge the nature of the hidden material.

The intensity of the reflected γ-radiation recorded in this case depends not only on the density of the bookmark material, but also on the geometric dimensions of the hidden bookmark.

A known x-ray device containing a radiation source, a means for placing a sample, a screen transformer made in the form of a truncated cone or a truncated pyramid with diverging capillary channels for transporting radiation, the walls of which are in the form of a side surface of a truncated cone or pyramid, at one end of which there is a means sensitive to radiation, and a photodetector.

Patent of the Russian Federation No. 2239822, IPC: G 01 N 23/04, Bull. No. 31, dated December 10, 2004. Prototype.

The prototype is difficult to manufacture, designed to work with an extended radiation source, the converter is essentially only a radiation collimator and only radiation sensitive means allows it to be considered a screen-converter.

The prototype allows you to identify and convert only one type of radiation, does not allow complex express analysis of the studied object.

The present invention eliminates the disadvantages of analogues and prototype.

The invention is aimed at increasing the efficiency of using fast neutrons, reducing the exposure time, reducing the influence of the background signal, improving the quality of received images, increasing the productivity of the process, simultaneously obtaining images not only in the neutron flux, but also in x-ray and gamma radiation, conducting a comprehensive express analysis the investigated object.

The technical result of the invention is to increase the efficiency and spatial resolution not only in a parallel, but also in a conical beam, expanding the device’s functionality, the possibility of express analysis of the samples under study, simultaneous registration of various types of penetrating radiation: fast neutrons, thermal neutrons, x-ray and gamma rays.

The technical result is achieved by the fact that in a device for radiography and tomography containing a source of penetrating radiation, means for placing the test sample, a transducer of penetrating radiation, made in the form of a truncated cone or a truncated pyramid with diverging channels for the transmission of radiation, the walls of which have the shape of a side surface truncated cone or pyramid, radiation sensitive means and means for detecting radiation are located on one end of the screen transducer i, the radiation transportation channels are made in the form of fiber optic scintillators and arranged in a bag in the form of a truncated cone or a truncated pyramid, the means for placing the test sample are made with the possibility of reciprocating and rotational motion, and the means for detecting radiation contains a deflecting mirror and not less than two optical channels, made in the form of successively arranged along the axis of the optical channel of the input projection lens with a filter, the amplifier is shown a scaling lens and a CCD.

A tool that is sensitive to the registration of radiation is located on the smaller end of the arranged package in the form of a phosphor layer. The fiber optic scintillators of the packet are coated with a phosphor layer.

The invention is illustrated in figure 1, figure 2 and figure 3.

Figure 1 schematically shows a device for radiography and tomography of objects with a mixed composition of penetrating radiation, where: 1 - a CCD matrix, 2 - a zoom lens, 3 - an image intensifier, 4 - a projection lens with a filter, 5 - a combined luminescent converter, 6 - deflecting mirror, 7 - means for placing the test sample, made with the possibility of reciprocating and rotational motion.

Figure 2 schematically shows a longitudinal section of a combined luminescent transducer 5, where: 8 - fiber-optic transport channels, 9 - phosphor layer scintillating in an additional section of the optical spectrum, transport channels 8 are composed of fiber segments 10, 11, 12 scintillating in different parts of the optical spectrum. The fiber segments 10, 11, 12, scintillating in different parts of the optical spectrum of channel 8, are connected in series (therefore, their positions are not shown in FIG. 1, but only sections of the cross section of the combined luminescent transducer 5 of different optical spectra are shown).

Figure 3 schematically shows a longitudinal section of one channel of a combined luminescent transducer 5, where: 10, 11, 12 is a section of fiber segments scintillating in different parts of the optical spectrum with parallel connection of fiber segments.

The device operates as follows.

When irradiating the test sample (not shown in the drawings) located on the accommodation device 7, made with the possibility of reciprocating and rotational motion, the combined transducer 5 receives a stream of fast neutrons and / or x-ray radiation, where the conversion of neutron and / or x-ray radiation into light radiation. Due to the different composition of the fibers 10, 11, 12 of the transport channels 8, the combined luminescent converter 5 allows you to convert different incident types of radiation into independent light fluxes of different spectral composition.

After passing through the combined luminescent converter 5, independent light fluxes of various spectral composition are separated by a deflecting mirror 6 and sent to projection lenses 4 with the corresponding light filters through separate optical channels of each type of radiation.

Then, the light flux enters the image amplifier 3 and then with the help of a scaling lens 2 onto the CCD matrix 1. Images are formed in various regions of the optical spectrum.

Selectivity of registration of a particular image is ensured by appropriate filters mounted on projection lenses 4.

Fiber optic converter 5 is universal, since its layout provides the ability to register fast neutrons, as well as thermal neutrons and x-ray and gamma radiation.

The additional layer 9 is essentially an additional channel for transporting its own type of radiation and, if necessary, reduces the longitudinal dimensions of the transducer 5.

A device based on a combined transducer 5 is effective for radiography both in a conical beam of fast neutrons and in the case of any combined radiation.

Claims (3)

1. A device for radiography and tomography, containing a source of penetrating radiation, means for placing the test sample, a screen-transducer of penetrating radiation, made in the form of a truncated cone or a truncated pyramid with diverging channels for transporting radiation, the walls of which have the shape of the side surface of a truncated cone or pyramid, on one end of the screen of the transducer is located a means that is sensitive to radiation, and means for recording radiation, characterized in that the channels of the protractor The radiation vectors are made in the form of fiber-optic scintillators collected from fiber segments scintillating in various parts of the optical spectrum and arranged in a bag in the form of a truncated cone or a truncated pyramid, the means for placing the test sample are made with the possibility of reciprocating and rotational motion, and means for detecting radiation contains a deflecting mirror and at least two optical channels made in the form of sequentially located along the axis of the optical channel one projection lens with a light filter, an image amplifier, a zoom lens and a CCD. 2. The device for radiography and tomography according to claim 1, characterized in that the fiber segments scintillating in different parts of the optical spectrum in the formed packet are connected in series. 3. The device for radiography and tomography according to claim 1, characterized in that the fiber segments scintillating in different parts of the optical spectrum in the formed packet are connected in parallel.

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