RU2558387C1 - Electro-optical display and method of making same - Google Patents

Abstract

FIELD: physics, optics.

SUBSTANCE: invention relates to converters for converting invisible electromagnetic radiation (infrared, X-ray, ultraviolet, gamma-radiation) into visible radiation. The invention can be used in analogue and digital display devices. The display is the form of a glass vacuum-sealed tablet-shaped stacked housing consisting of two glass covers - cathode and anode, having film electrode coatings that are vacuum-tight sealed at the edge by low-melting lead glass. A microcapillary plate is placed between the covers. The cathode and anode covers of the housing are made of heat-resistant glass, the anode cover is thin (0.5-1 mm) and the cathode cover is extremely thin (less than 0.5 mm). The cathode cover is reduced to a stack by polishing with a thin abrasive and by chemical-mechanical polishing. The microcapillary plate is mechanically, electrically and optically tightly connected to the anode and cathode covers by through technical adjustment of dimensions and atmospheric pressure on the cover of the assembled evacuated stack. The cathode is made of two incompatible versions of materials - non-sensitive or, conversely, sensitive to visual luminescence light. The anode film is made of transparent conducting material and has a refraction index and thickness which facilitate interference transmission of visual luminescence light. A phosphor and a gas-absorber are made in the form of nanopowder coatings on the surface of microcapillaries of the microcapillary plate. The nanopowders are deposited from a common suspension in a volatile liquid after "saturation" of microcapillaries, followed by evaporation when heating with light and simultaneous exposure of the microcapillary plate to ultrasound. The amount of phosphor and gas-absorber varies and is selected in specific versions of the displays by varying the composition of the suspension. The brightness and definition of the image of the finished device obtained at the output are controlled by varying voltage across the microcapillary plate in a wide range.

EFFECT: improved controllability of image parameters; longevity of the sensitive cathode; large specific surface area of the phosphor and gas-absorber coatings; broader operating functions and applications.

5 dwg

Description

The invention relates to converters of invisible electromagnetic radiation (infrared, x-ray, ultraviolet, gamma radiation) to visible. It can be used in visualization devices operating on analog and digital principles.

DESCRIPTION OF THE INVENTION

The conversion of invisible electromagnetic radiation (EMP) of infrared, x-ray, ultraviolet, gamma radiation into the visible is an important area of science and technology [1, 2]. Imaging devices are called visualizers. Visualizers come in two forms - “passive”, without amplification, and “active”, with amplification.

Non-gain visualizers act as direct radiation converters. A known, for example, X-ray luminescent screen [3], in which X-ray radiation is directly converted into a visible luminescent layer of an X-ray sensitive phosphor.

The advantage of these visualizers is the simplicity of their designs and manufacturing methods. Their significant drawback is poor conversion sensitivity.

Internal-enhanced visualizers act as radiation converters in which the conversion takes place in several stages. First, under the influence of EMR, electron emission occurs, and then the electron energy is converted into visible radiation. Such converters are called electron-optical (EOC).

A large number of variants of image intensifiers and visualizers based on them are known [4]. The principle scheme of their action is that weak external radiation creates electron emission in the layer of the device window, the flow of which is amplified by the field and directed to the anode. At the anode, electrons bombard a phosphor layer that emits light.

Image intensifier tubes of the first versions have an electrode system to enhance the electron flow. They are relatively bulky and not economical.

Image intensifier tubes of high complexity and efficiency classes have a microchannel plate (MCP) as an electron flow amplifier. This allows you to drastically reduce the dimensions of the device, reduce power consumption, increase conversion efficiency.

The structure of the MCP and its action.

MCP is a cell formed by a large number of microchannels - microcapillaries with an internal semiconducting surface, figure 1 [5]. The axis of the capillaries is inclined to the plane of the plate (usually up to 20 °). When an incident particle-corpuscle (electron, photon, x-ray or gamma ray) enters the channel, it knocks electrons from its wall, which are accelerated by the electric field created by the voltage applied to the ends of the channel. Electrons fly along their paths until they hit the wall, in turn, knocking out even more electrons. This process is repeated many times as it travels along the channel, forming an electronic avalanche. The gain in the channel g is determined by the relation: g = exp (G - channel length and diameter, L / w ratio (gauge) for standard MCPs up to 100. The values of the electron flux gain are 10–10 ⁵ .

Figure 2 shows (reference) graphs of gain curves for MCP.

Figure 3 schematically shows a section of the image intensifier tube in the usual application scheme of the MCP.

In Russia, the production of MCP [6] has been established specifically for the purpose of enhancing the electron beam with the following parameters: plate diameter - 10-50 mm, thickness - more than 0.2 mm, channel diameter - up to 10 microns.

Description and criticism of analogues and prototype.

In modern ICs, a photocathode based on gallium arsenide (GaAs) activated on the surface with cesium oxide (Cs: O) is usually used. The photocathode is very demanding on the value of the residual pressure and is easily susceptible to poisoning, which leads to a decrease in its sensitivity and shorten the life of the image intensifier tube. Therefore, photocathode protection is used in the form of an ion-barrier film deposited on the input surface of the MCP. The ion-barrier film prevents the release of positive ions and neutral gases from the MCP channels and, thus, preserves the photocathode, which increases the life of the device. However, the use of an ion barrier film has negative aspects. Its application degrades such characteristics of the image intensifier as the signal-to-noise ratio, resolution, and dark background level, which reduces image quality and reduces the range of the device.

It was shown in [8] that prolonged thermal degassing at temperatures between 300 and 520 ° C and electronic cleaning can reduce the subsequent desorption of gases to such low values that they can be sorbed by an appropriate getter.

Known EOP [9], which does not contain an ion-barrier film, with a declared durability of 7500 hours. It contains a photocathode, a microchannel plate, a receiver, for example, a luminescent screen, a titanium-tantalum wire getter, which are placed in the casing of the tube, filled to a certain pressure with cesium. The disadvantage of this technical solution is the poor durability of the device, since cesium does not form stable compounds with the internal elements of the device and does not have sufficient sorption ability to ensure a long service life of about 15-20 thousand hours

Known electron-optical Converter [7], selected as a prototype of the claimed, which contains the cathode 1 and the anode screen 3, a microchannel plate MCP 2 (Fig.3, 4). Each MCP channel is provided with an individual getter in the form of a coating 8 (Fig. 3) from a substance or compound of two or more substances having a high sorption capacity and a secondary emission coefficient greater than unity, for example, from a compound of cesium with antimony or tellurium. In addition, the MCP has individual getters on the input (from the cathode) and output (from the anode) surfaces. The anode screen (flat plate) has a phosphor layer coated on top to protect it and improve gas absorption by a film of aluminum and a getter 9. Secondary electrons exit the MCP and, under the action of an accelerating field potential (5000-6000 V) break through the getter coating, an alumina film, film of aluminum and hit the phosphor coating, exciting luminescent radiation.

The prototype has a relatively complex design of the housing with several elements placed in it, 4 electrode leads through the side wall of the housing, the need for three power supplies, including high-voltage up to 6000 V (Fig. 4). The anode window should be transparent to light (for example, glass). The cathode is made of a material that transmits well the excited radiation (in this case, IR) and does not transmit light (for example, germanium). Both dissimilar windows are elements of the body. Due to the large difference in the KTP of their materials, taking into account the need for high-temperature heating during vacuum sealing and degassing of the elements of the device, maintaining its tightness will be problematic and will require some special complex structural and technological measures.

The main disadvantages of the prototype are the following.

1. In areas near the anode and cathode there is an extended space with large field strengths where ionization of gas atoms occurs, and ions have the ability to bombard and destroy the cathode and anode. In these zones, the absorption of ions will be negligible - formed in the gap, they freely fly to the cathode and anode.

2. Coating the phosphor layer with a protective film of metal (aluminum) dramatically (more than 10 times) reduces the energy and the number of electrons that excite the phosphor. This leads to large energy losses of the device and the problems of forming a clear bright image.

3. Coating the surface of the microcapillaries with a film-conducting material of the getter will lead to a change in the resistance, operating voltage, and other parameters of the MCP, both due to the conductivity of the film and due to a change in the efficiency of collisions of photoelectrons (first collision) and secondary electrons with a coating. This will introduce significant distortions and some kind of instability in the operation of the device.

4. The main source of vacuum deterioration will not be the MCP, as the authors of the patent claim, but the case itself with its complex structure of thermomechanically inconsistent elements. The formation of "parasitic" gas and ions in the microchannels of the MCP and their release from long microcapillaries are generally unlikely. In microchannels, the main contribution to the electron beam is made by secondary electrons, which have energy values (in this case, volts and tens of volts) that are not sufficient for electronic stimulation of gas separation (at least hundreds of volts are needed) [10, 11]. In addition, ionization in microcapillaries is unlikely - there are no high fields and charge paths. And, finally, “flying out” to atoms and ions from the capillary with length to diameter ratios much larger than 10 is unlikely.

The rationale and description of the design of the claimed option.

These disadvantages of the prototype are eliminated in the claimed embodiment by the fact that the anode, cathode and MCP are mechanically and electrically connected to each other, the phosphor and getter materials in the form of nanopowders are placed on the surface of the microcapillaries, the device case has the simplest structure and the minimum number of elements thermomechanically matched to each other .

These innovations eliminate the influence of the mutual arrangement of structural elements (empty gaps between the electrodes and the MCP) on the properties of the output fluorescent radiation and degradation of the cathode. Each microchannel at the same time works as a separate independent element. In addition, the effect of unwanted current leakage on the surface coating of the microchannels is reduced and the controllability of the parameters with changing voltage is improved.

The current flows in the channel in two ways - in vacuum and along the surface coating. Surface coating is necessary to remove charge from it and is approximately uniformly distributed constant ohmic resistance. Powder coating, unlike a continuous film, practically does not change the resistance of the coating along the axis of the channel. But it can usefully increase it across the channel if powder particles, such as phosphors, are poorly conducted.

For the current in vacuum, one can take the action of the Richardson formula (the law of the second two), from which one can find the formula for the resistance of the vacuum "wire". This resistance will be proportional to the square of the channel length and inversely proportional to the root of the voltage. Then it follows that with an increase in the length of the channel (the path of the electrons in the channel) and a decrease in voltage on it, the role of shunting conductivity (undesirable current leakage) of the coating of microcapillaries increases.

This factor strongly affects the current gain in the MCP and the distribution of the current along the channel. A situation is possible when a process in a channel vacuum occurs, but there is no current on the anode electrode - the current is integrally shunted by coating the channel surface. This leads to poor controllability of the properties of the MCP by voltage - a small value in the range of its influencing changes. The application of the phosphor to the surface of the channels completely eliminates this effect - part of the electrons of its flux at any point on the surface of the channel excites the phosphor, which, therefore, emits and creates an image at almost any voltage value on the MCP, which allows it to be controlled over a wide range of voltage changes.

A simple calculation of the geometric parameters of the MCP leads to the ratio of the surface area of all microchannels S to the MCP area s-3L / w, where L is the length of each of the capillaries (thickness of the MCP), w is the diameter of the capillaries.

For cases of striving for the highest gain (Fig. 2), the S / s ratio will reach at least 100. That is, the surface area of the microchannels will be 100 times the area of the MCP, which allows this circumstance to be used in wide possibilities. This, in particular, leads to the idea of the application, to apply materials (in the form of nanoparticles) to the working elements of the device — a phosphor and a getter — on the surface of the microchannels.

Suppose that, for reasons of the maximum non-reciprocal effect of nanoparticles of two different materials, their applied amount will be such that they cover only half the area S. Then each of the materials will have an average of 1/4 of the area S. That is, for each square centimeter of the plate area, the working coating of each materials can reach 25 cm ² , which with a margin is sufficient for the effective operation of the device.

The design diagram of the claimed embodiment is presented in figure 5. It displays:

1 - glass cathode plate (cover 1),

2 - anode glass plate (cover 2),

3 - the perimeter of the junction plates low-melting glass (perimeter),

4 - film electrode-anode (anode),

5 - film electrode-cathode,

6. - cathode sensitive layer (cathode),

7 - microcapillary plate (MCP),

8, 9 - supplying external electrodes (electrodes),

10 - optical matching element (optical element).

11 - an element of enlightenment.

The cathode plate 1 of heat-resistant (for example, molybdenum) glass should be as thin as possible (less than 0.5 mm) in order to pass the radiation received by the device well.

The anode plate 2 of heat-resistant (for example, molybdenum) glass should be thin enough (0.5-1 mm) to ensure a minimum distance to the external spectral element.

The plates 1 and 2 are shifted relative to each other or the perimeter so that outside the perimeter of the device there are certain zones of their surface, sufficient for connecting the electrical leads 8 and 9.

The perimeter of the junction of 3 plates is a low-melting glass with a CTE close to the cathode and anode plates.

Film electrode-anode 4 - a film of a conductive transparent material with a refractive index greater than 1.4 (for glass) with a thickness equal to a quarter of the wavelength of luminescent radiation, for example, indium tin oxide (ITO), for which the refractive index is close to two, the film thickness about 0.1 microns.

The film electrode-cathode 5 is a thin (of the order of 0.1 μm) film of a conductive material, for example aluminum, which does not absorb received radiation and reflects luminescent radiation.

The cathode layer 6, sensitive to the received photo, x-ray, gamma radiation. It may or may not be sensitive to visual luminescence light.

MCP 7 has a nanofilm semiconducting secondary-emission reflective and nanopowder coatings on the surface of the walls of the microchannels. Nanopowders - phosphor and getter.

The supply electrodes 8 and 9 are a metal wire or conditioner welded or glued with conductive adhesive to the surface of the film electrodes of the anode and cathode.

The optical matching element 10 should pass the received radiation well and not pass any background radiation. Standard optical parts can be used as such elements: for IR, a germanium plane-convex (hemispherical) lens; for ultraviolet radiation - a quartz enlightened plane-convex (hemispherical) lens; for x-ray and gamma radiation - special elements, such as Kumakhov lenses.

The enlightenment element 11 is an interference plate or a layered structure that allows only the transmission of luminescent radiation and blocks the background illumination from the side of the anode cover.

Description of the manufacturing method of the claimed option.

A manufacturing method includes the following process steps.

1. Application of junction 3 perimeter material onto large glass plates-blanks by the method of screen printing and subsequent annealing from purchased standard material (coated glass plates) manufactured for display manufacturing.

2. The manufacture of plates 1 and 2 with a film coating of the electrodes 45 by standard methods of cutting (from blanks after operation 1) and processing.

3. Coating the cathode plate with a layer sensitive to the received radiation by standard methods.

4. Preparation of the INC (purchased).

5. The assembly of packages from fiberglass plates 1 and 2 (after operations 2 and 3) and MCP 7 (after operation 4). Installation of packages in special cartridges for vacuumization.

6. Evacuation, annealing and sealing of packages (after operation 5). In this process, the activation (temperature and electron-stimulated degassing) of nanopowders on the surface of microchannels is carried out.

7. Grinding into size and polishing packages from the side of the cathode plate. Processing (cleaning) packages.

8. The connection of the electrode leads 8 and 9 by the methods of resistance welding or gluing with conductive glue.

9. Attaching the optical element 10 by gluing onto a superthin optical glue or glue with a filler. Optical glue is used for gluing elements of light optics, glue with a filler - for gluing x-ray optics. The filler should be made of light (to transmit x-ray or gamma rays) opaque to light material.

Of all this sequence of operations, the original “MCP preparation” and “grinding to size” are original. The MCP itself, as a preform, is a purchased standard product with a nanolayer on the surface of microcapillaries, effective for secondary emission.

“Preparation of the INC” consists of the following several operations.

4.1. Synthesis of nanopowders of materials - with a high level of luminescence (for example, AlGaAs); with a high degree of gas absorption (e.g. cerium). This operation is beyond the scope of the claimed embodiment of the invention. It is produced by specialized industry units. Widespread methods of preparative chemistry are best suited for this manufacture. The product of this method is a suspension of nanopowder suspended in a well-volatile solution (acetone, alcohol).

4.2. Application of nanopowders on the surface of microcapillaries of MCP from suspension (after operation 4.1). A method is proposed for the slow evaporation of a volatile component from microcapillaries of a free-hanging MCP heated by light when exposed to a weak level of ultrasound. Ultrasound promotes uniform deposition of nanopowder on the surface of microcapillaries. The modes of heating and exposure to ultrasound are selected in the specific conditions of production and design of devices. The amount of applied material varies and is selected by changing their concentration in suspension.

"Grinding to size" of the package (cathode plate) is carried out by grinding methods with fine-grained abrasive powders (for example, M1) and deep chemical-mechanical polishing. Such a “delicate” treatment allows you to avoid micro-destruction in the cathode fiberglass plate and achieve its maximum strength with a minimum thickness. This is of great importance in order to achieve minimal absorption of weak received radiation in the glass of the cathode plate, which acts as an input window. Description of the operation of the claimed device. The claimed version of the device operates as follows. When illuminated with an analyzed invisible radiation - gamma, x-ray, ultraviolet, infrared - the optical matching element 10 passes and focuses it through a thin cover 1 and a superthin film of the electrode 5 on the cathode 6, without passing background radiation. When voltage is applied to the electrodes 8 and 9 connected to the film anode 4 and through the film electrode 5 to the cathode 6, the emission of electrons from the cathode to the microchannels of the MCP 7 occurs, with a number and a flux proportional to the energy flux of the received radiation. In microchannels of the MCP under the action of a field with potentials from the applied voltage and due to secondary emission, the electrons are accelerated, forming an avalanche in their flow. Some of them interact with the nanoparticles of the phosphor coating and create light emission from a visual image, the energy flux of which is proportional to the magnitude of the electron flux. Nanopowder getter coating provides the necessary vacuum inside the device during its manufacture and operation. Vacuum tightness and strength of the device casing are provided by covers 1 and 2, connected tightly around the perimeter 3 by low-melting glass.

In the operation of the device, it is important to obtain the required level of a number of parameters, the main of which are the brightness and contrast clarity of the image obtained at the output of the device — the anode cover.

Brightness can be estimated as follows.

The current in the cross section of one microchannel of the MCP at a distance x is the coordinate counted from the cathode

J ₁ (x) = J ₀ exp (Kx),

where J ₀ is the emission current of the cathode in the cross section of one capillary created by the received radiation and the action of the field on the cathode, K is the gain determined by the curves of FIG. 2.

The current density is J ₁ [π (w / 2) ² ] ^-1 . On the surface of the capillary in a strip of width dx, the current will be J [π (w / 2) ² ] ^-1 (πw) dx. Then the current in the strip dx - J (x) = J ₀ [π (w / 2) ² ] ^-1 (πw) exp (Kx) = J ₀ (4 / w) exp (Kx) dx.

The voltage on the element dx will be: V _x = Vw (L sin φ) ^-1 , where: V is the voltage on the MCP, φ is the angle of inclination of the capillaries to the vertical plane of the MCP. The power supply of the element dx will be - J (x) V _x , and the light output - ηµJ (x) V _x , where η is the luminous efficiency of the phosphor (Lm / W), μ is the fraction of the capillary surface with the phosphor coating. Substituting the values of J (x) and V _x and integrating over the length of the capillary, we obtain the expression for the light output of one capillary

i = 4ηµJ ₀ V (KL sin φ) ^-1 exp (KL).

Substituting approximate real values for practice into this expression: V = 1000, exp (KL) -1000, KL = 40, sin φ = 0.5, η = 30, μ = 0.3, it turns out: i = 10 ⁶ J ₀ . Multiplying the left and right parts by the number of microcapillaries of the MCP, you get the light output from the entire device - I = 10 ⁶ J Lm, where J is the emission current of the entire cathode (in amperes).

For modern photocathodes, the emission currents (IR sensitivity of the photocathode) are approximately 10 ^-3 A per 1 W of received IR power [12]. Then the estimated light output will be 10 ³ Lm / W. With a clearly visible brightness of the image on the screen of the order of 100 Cd / m ² = 300 Lm / m ² = 0.03 Lm / cm ² , an acceptable photocathode sensitivity of 3.10 ^-5 W / cm is obtained. The sensitivity threshold values at the level of 10 ^-5 W / cm are quite acceptable for many applications. For example, the density of thermal radiation of the human body is at the level of 10 ^-2 -10 ^-4 W / cm ² [13].

For options for receiving other types of radiation, for example, x-ray, it is possible to predict a more favorable situation than for the photocathode, due to the higher energy activity of these radiation.

The contrast clarity of the image obtained at the output of the device is deteriorated mainly by the undesirable mutual internal illumination of the elements of the device by the radiation of the phosphor. Therefore, in all variants of visualizers, measures are taken to eliminate this influence. Basically, this is a dull blocking of radiation due to the coating of the phosphor film with a film of metal, for example aluminum. This, however, leads to a big problem associated with overcoming the metal film by electrons and the need for a sharp increase in the voltage at the anode (up to 10000 V).

In the claimed embodiment, this problem is solved by mechanically, electrically and optically tight contact of the surfaces of the anode and cathode to the surface of the MCP. This allows its own radiation to circulate only within each of the microchannels, without illuminating the others. In this case, the reflective properties of the surface of the microchannels are important, which are determined by the coating of their surface and the degree of full internal reflection. These properties are determined and provided by specific structural and technological measures to ensure the properties of the surface coatings of microchannels in the development of specific options for devices - the choice of material, structure and geometry of the coating. At the same time, an ideal MCP made of black glass could be ideal. Such glass is produced and it can be used in the manufacture of the tube, the original for the production of MCP.

Important in this case is the nature and magnitude of the effect of radiation circulating in the microchannel on the cathode. Two cases are possible here: the absence and presence of this influence.

The absence of the effect of intrinsic radiation on the cathode is ensured by the selection of the cathode material. For the case of received infrared radiation, these can be quantum dots of narrow-gap semiconductors sensitive in a very narrow band of the spectrum, determined by the particle size of the material. For other cases, semiconductor materials are selected that are not sensitive to the self-radiation of the device, which is easy to do due to the fact that the photon energies of the self-radiation are much lower than the photon energies of the received radiation.

An interesting case is the influence of intrinsic radiation on the cathode. This will increase the effect of the received radiation in each microchannel. Fundamentally, the internal gain in the channel should not eliminate the proportional dependence on the magnitude of the received radiation (the magnitude of the primary cathode emission current). In this case, one can select the value of the internal gain by varying the cathode material, the fraction of the surface of the microcapillaries covered by the phosphor, and the voltage on the MCP. These measures will increase the sensitivity of the instrument.

EXAMPLES OF EXECUTION, ADVANTAGES, APPLICATION

Examples of execution, it is advisable to start by taking into account the properties of the MCP. In accordance with FIG. 2, it is necessary to select the desired gain parameter. Let it be - 1000. Then the MCP option is selected with a diameter of microcapillaries of 25 microns and a caliber of 40, i.e. plate thickness 1 mm. Given the largest diameter of the MCP of the manufacturer, say, 50 mm, a square plate is formed with a side size of 35 mm. A phosphor nanopowder is coated on the surface of the microcapillaries, albeit with a red glow, for example, the type of conductivity and composition of p-Ga _0.8 Al _0.2 As, and a getter, for example, Cs ₃ Sb.

Glass plate-covers will have dimensions 45 × 40 mm. A conductive spectrally transparent In _x Sn _1-x O layer is formed on the anode plate. On the cathode plate is a film electrode, for example, thin (0.1 μm) aluminum, a cathode nanopowder coating of one of the options: for receiving infrared radiation, for example, quantum dots the composition of the narrow-gap semiconductor InSb; for receiving gamma, x-ray or ultraviolet radiation - a wide-gap semiconductor, for example, GaN.

The assembly of the package is done so that the plates are moved relative to each other by 5 mm along the long side. Obtained edge protrusions, on which, after assembly and sealing of the package, the connection of supply electrodes is formed. The sample will have overall dimensions of 50 × 40 mm and a thickness of 3 mm, which, after finishing the plates with grinding, will become 1.5-1.8 mm. The dimensions of the internal space will be approximately 36 × 36 × 1 mm.

Elements of spectral-optical blocking of background illumination are added to such a packet. Blackening is applied to all unclosed areas of the housing. For ease of use, such a flat device can be placed in a frame with a handle. The optical element for receiving radiation may be removable.

Power consumption 1-3 watts (estimated).

Advantages of the device over all known options for visualizers:

- multifunctionality of the action - visualization of several types of received radiation; manual or hardware use;

- high visualization sensitivity due to the large specific area of the phosphor coating - not less than 10 times to the anode area (MCP);

- great durability due to the absence of ultrahigh voltages (10000 V) and near-electrode empty spaces for the generation of ions and their bombarding of the cathode and anode;

- efficiency due to the lack of high voltage consumption at the anode electrode; no loss of current closure in the MCP through a conductive continuous getter film - in the claimed embodiment, a powder (not continuous) coating is used with a small fraction of the occupied surface;

- the relative simplicity of design and technology by reducing the number of elements and the use of active materials in the form of powders;

- ease of use due to the miniature size of the device and the use of one relatively low-voltage source instead of two or three.

The principal distinguishing points of the claimed technical solution are: direct contact of the MCP with both electrode plates and the application of a phosphor and a powder getter on the surface of the MCP microcapillaries.

The first solution eliminates near-electrode empty zones, which are a source of ions that destroy the working coatings of the electrodes. In addition, these zones impair the clarity of the image, being a source of uncontrolled illumination of the working elements and aperture blurring of the brightness of the display elements. In addition, the contacting of all three elements of the device allows minimizing the thickness of the electrode plates due to the fact that they do not need to keep the mechanical loads of the external atmosphere in a free state. This allows you to have extremely small radiation energy loss and image blur. All, ultimately, leads to the fact that each microchannel of the MCP works as a separate element that is not connected with others.

The location of the phosphor coating directly in the microchannels greatly increases the radiating surface. This increases the sensitivity of the display and allows a wide variation of the current load (gain of the MCP). For example, you can go into the region of small diameters of the channels and, thereby, increase the geometric resolution of the display. As can be seen in figure 2, the transition to small w leads to a sharp decrease in gain - 10 instead of 1000. In conventional devices, this will lead, respectively, to a 100-fold decrease in image brightness. In the claimed embodiment, the phosphor area is fundamentally 100 times increased, that is, the brightness will not change.

Powder deposition of a getter, instead of continuous film, eliminates its effect on the conductivity of the active coating of the surface of microcapillaries.

The device can be used as a visualizer of infrared radiation in thermal imagers and night vision devices; X-ray and gamma radiation in the control of local places of defects in materials, living systems; ultraviolet radiation in the control of biosystems.

The device can be used in portable equipment with semi-automatic and manual control.

New applications are associated with express control in medicine, everyday life, crowded places.

Information Sources Used

1. Visualization. http: //megabook.m/article/VISUALIZATION.

2. Physics of visualization of images in medicine. Volume 1, 2. Ed. S. Webb. Moscow. Peace. 1991 year

3. X-ray luminescent screen (RF patent No. 2476943).

4. Electron-optical converters.

http://femto.com.ua/articles/part_2/4695.html

5. Microchannel plates, http://profbeckman.narod.ru/radiometr. files / L10_10.pdf

6. Microchannel plates, http://www.ru.all.biz/mikrokanalnye-plastiny-bgg1080825

7. Patent (RU) 2331948. Priorities: filing an application - 01/09/2007; the beginning of the patent - 01/09/2007; publication of the patent - 08/20/2008. Author Aksenov V.A. Patent holder: ZAO Ekran FEP (RU).

8. Boutot J.-P., Acta Electron, 14, 243, 1971.

9. US Patent No. 6,437,491 of 08/20/2002

10. Secondary electron emission. http://femto.com.ua/articles/part_1-/0611.html

11. Electron-stimulated desorption, fs.nashaucheba.ru/docs/180/index-430389.html

12. P.V. Bukharov. Photocathodes of modern image intensifier tubes. TUSUR reports, No. 2 (24), part 1, December 2011.

13. Radiation of real bodies and the human body, http://www.biochemi.ru/chems-851-1.html

Claims (1)

Electron-optical visualizer of invisible electromagnetic radiation, manufactured by methods: cutting, grinding, polishing plates; applying film and powder coatings to structural elements; preparation and assembly of structural elements; evacuation, degassing and sealing; connection of electrodes and optical elements, consisting of: a vacuum-tight flat package housing having two covers, a cathode and anode, external cathode and anode electrodes connected to them; attached to the cathode cover of an optical element selective in the spectrum of received radiation, such as a lens; attached to the anode cover of an optical antireflection element; film anode; sensitive to the received radiation cathode with its film electrode; microchannel fiberglass plate (MKP) with a secondary-emission nanofilm semiconducting and reflective coating of the surface of the microchannels; phosphor coating, which creates visual luminescence in the device; getter coating; characterized in that in order to improve the control of image parameters, increase the durability of the sensitive cathode, increase the area of the phosphor and gas absorption coatings, expand the functions of applications and applications, the cathode and anode covers of the casing are made of heat-resistant glass, for example, molybdenum, the anode is thin (0.5-1 mm), cathodic - extremely thin (less than 0.5 mm) after finishing in the assembled bag by grinding with a thin (less than 1 micron) abrasive and chemical-mechanical polishing; MCP is mechanically, electrically and optically tightly connected to the anode and cathode covers due to technological adjustment of sizes and atmospheric pressure on the covers of the assembled vacuum package; the cathode is made of materials of two incompatible options - not sensitive or, conversely, sensitive to light visual luminescence; the anode film is made of a transparent conductive material, such as indium tin oxide, and has a refractive index and thickness that provides interference transmission of light of visual luminescence; the phosphor and getter are made in the form of coatings of nanopowders on the surface of microcapillaries by applying in a technological cycle from a total suspension of nanopowders in an easily volatile liquid after it is “impregnated” with microcapillaries, followed by evaporation by heating with light and simultaneous exposure of the MCP to ultrasound; moreover, the amount of phosphor and getter and, accordingly, the size of the nanopowder surface area of the microcapillaries vary in specific versions of the visualizers by selecting the composition of the suspension; the brightness and clarity of the output image of the finished device are regulated by changing the voltage on the MCP in a wide range of its values.

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