RU71451U1 - TWO-ORDER RADIATION DETECTOR - Google Patents

Abstract

The utility model relates to the field of radiation registration by radiation methods. The technical result is to expand the energy range of registration of penetrating radiation and their types, increase the efficiency of collection of light arising in the scintillator when an ionizing particle passes through it and transport it to photodiodes, increase the spatial resolution of registration. The technical result is achieved by the fact that the block is made in the form of a scintillating plate with rows of light-emitting fibers fixed perpendicular to each other fixed on it on different planes, and the photodiodes of the light-emitting fibers are located at the ends of the plate and connected to the registration circuit with an output register. 1 n.p.f. 1 cpf 2 ill.

Description

The utility model relates to the field of radiation registration by radiation methods and can be used for flaw detection of products under industrial and field conditions, as well as for detecting a source of ionizing radiation at checkpoints, railway stations, airports, customs services, etc.

Known neutron detector containing a fiber module, assembled from layers of polymer scintillating optical fibers, stacked alternately in two mutually perpendicular directions, and an electron-optical system for recording optical radiation emerging from the ends of these fibers, the electron-optical system contains photodetectors. U.S. Patent No. 4,942,302, IPC: G01T 3/06, 1990

The specified device has low efficiency, because does not provide two coordinate registration of recoil protons with a range less than the cross section of a single fiber; and also has restrictions on the number of fibers in the layer and the number of layers imposed by the number of photodetectors used. The device has a limited spatial resolution, determined by the cross-section of the fiber.

Known neutron detector, made in the form of a block of layers of polymer scintillating optical elements, stacked alternately in two mutually perpendicular directions, containing an electron-optical system for recording optical radiation emerging from the ends of these fibers.

The ends of the fibers are located in the planes of the faces of the fiber parallelepiped formed by the layers of fibers, and the electron-optical system is made in the form of position-sensitive photodetectors that are optically paired with the corresponding faces of the fiber

parallelepiped. The diameter of the fibers is equal to half the mean free path of the recoil proton in the fiber material.

The electron-optical system contains subsystems into which translucent plates are introduced for branching optical power to high-speed receivers. Patent of the Russian Federation No. 2119178, IPC: G01T 3/06, 1998

The neutron detector is difficult to implement, has low efficiency, low spatial resolution, is designed to detect fast neutrons, does not allow to identify radiation and determine the direction of radiation. The sizes of the elements are limited and are fibers with a transverse size of not more than 1 mm.

Known multilayer detector, made in the form of a block of layers of polymer scintillating optical elements made of a set of materials, the density of which increases monotonically from the first row to the last layer and photodetectors.

A handout of the Institute of Solid State Physics of the Russian Academy of Sciences, Chernogolovka, Moscow Region. 2005. "Anti-terrorism translucent installations for the rapid detection of explosives."

The disadvantage of such a detector and the installation as a whole is the need to obtain images of hidden objects when x-rayed by radiation of specific objects in an explicit manner. The detector is designed to detect only one type of radiation, namely, x-ray and cannot detect neutron radiation.

Known coordinate sensitive detector containing a block of hydrogen-containing scintillating optical elements, stacked in rows alternately in two mutually perpendicular directions, and photodetectors. In the detector, scintillating optical elements are made in the form of rods with a rectangular cross section, on one of the faces

grooves of each rod are made, scintillating fibers are placed in the grooves, photodiodes are located at the ends of the fibers, photodiodes are provided with leads for connection with scintillation burst detection circuits. Patent of the Russian Federation for utility model No. 544440, IPC: G01T 3/06, 2006. Prototype.

The prototype has a relatively low manufacturability (processing of each individual rod, making grooves in it, etc.) of manufacturing the detector and low spatial resolution, determined by the cross section of the rod.

This utility model eliminates the disadvantages of analogues and prototype.

The objective of the invention is to develop a technologically advanced detector of ionizing radiation to visualize the spatial distribution of the flux density of ionizing radiation with improved properties: increased efficiency and spatial resolution, stability, mechanical strength, and service life. Development of detectors of almost any area that do not require high-voltage power, special rooms, etc.

The technical result is to expand the energy range of registration of penetrating radiation and their types, increase the efficiency of collection of light arising in the scintillator when an ionizing particle passes through it and transport it to photodiodes, increase the spatial resolution of registration of an ionizing particle.

The technical result is achieved by the fact that in a two-coordinate detector containing a block of scintillating optical elements with photodiodes equipped with leads for connection with scintillation flash detection circuits, the block is made in the form of at least one scintillating plate with rows of light-emitting fibers fixed to it on different planes ,

located perpendicular to each other, and the photodiodes of the light-emitting fibers are located at the ends of the plate and connected to the registration circuit with the output register.

A two-coordinate detector contains at least two pairs of scintillating plates with fixed rows of light-emitting fibers located perpendicular to each other, with the possibility of plane-parallel movement of the next pair relative to the previous pair with a step not exceeding the diameter of the light-emitting fiber.

The essence is illustrated in figures 1 and 2.

Figure 1 presents a diagram of a two-coordinate detector, where:

1 - scintillator plates, 2 - photodetectors, 3 - light-absorbing layer (plate) located between the plates.

Figure 2 presents a diagram of a two-coordinate detector, where;

1 - scintillator plates with a transverse dimension D,

2 - photodetector devices (photodiodes), 4 - examples of the direction of movement of the ionizing particle.

Consider the operation of the device using the example of a coordinate-sensitive detector from one plate.

The one-coordinate coordinate-sensitive detector consists of a scintillating plate 1, photodiodes 2 located at the ends of the plate, and an electronic board with an output register (the board is not shown in the figures).

The material of the scintillator plate 1 as a light collector is transparent to light.

When an ionizing particle passes through the plates of the scintillator 1, the signal appears in several nearby photodiodes 2, the number of which is determined by the number of photons generated. The determination of the coordinates of the scintillation flash is carried out on

based on a comparison of the amplitudes of the signals received from various photodiodes 2 and finding the center of gravity of the spatial distribution of these signals.

Photodiodes 2 are connected to an electronic board, which, when a signal is received from photodiode 2, generates an analog signal, digitizes it and enters it into the output register with the arrival time, the number of light-emitting fiber 4 and the amplitude of its signal.

The material of the scintillating plates 1 for detecting thermal neutrons is lithium-6 containing scintillating glass.

The material of the scintillating plates 1 for recording charged particles is a scintillating glass or a plastic scintillator. The material of the scintillation plates 1 for detecting gamma radiation is a scintillating glass, a plastic scintillator, or NaI (Tl) plates with glass exit windows.

To increase spatial resolution, a single-coordinate coordinate-sensitive detector is made of several layers. Moreover, adjacent layers are made with the possibility of their plane-parallel movement relative to each other. The spatial coordinate is determined from an analysis of the amplitudes of the signals received from various scintillating plates 1 and photodiodes 2 of the coordinate-sensitive detector as a whole.

The step by which one layer is shifted relative to the other is changed depending on the number of layers ranging from 0 to size D of the scintillator plate 1, or scattered according to the law of random numbers within the specified limits.

To determine the two coordinates of the intersection of the ionizing particle of the recording device, it is made of two identical

single-axis detectors with mutually perpendicular arrangement of photodiodes 2, each of which works as described above. As is known, light-emitting fibers provide an efficient collection of light arising in the scintillating plate 1 during the passage of an ionizing particle and the transport of light to photodiodes 2.

Therefore, to simplify the design as a whole and to increase the efficiency of registration of ionizing particles, the scintillator plates 1 are equipped with light-emitting fibers (not shown in the figures).

To reduce light losses in the plate of the scintillator 1, the light-emitting fibers with the plate of the scintillator 1 of the scintillator are connected using optical contact (glue) - an immersion medium with a close (or intermediate for fiber materials, scintillator, scintillator exit window) refractive index.

The presence of light-emitting fibers on the scintillator plate 1 made it possible to produce a simple two-coordinate radiation detector with the arrangement of light-emitting fibers on both sides of the scintillator plate 1.

Claims (2)

1. A two-coordinate detector containing a block of scintillating optical elements with photodiodes equipped with leads for connecting to scintillation burst registration circuits, characterized in that the block is made in the form of at least one scintillating plate with rows of light-emitting fibers fixed to it on different planes, located perpendicular to each other, and the photodiodes of the light-emitting fibers are located at the ends of the plate and connected to the registration circuit with the output register. 2. The two-coordinate detector according to claim 1, characterized in that it contains at least two pairs of scintillating plates with fixed rows of light-emitting fibers located perpendicular to each other, with the possibility of plane-parallel movement of the next pair relative to the previous pair in increments not exceeding the diameter light emitting fiber.