KR102268839B1 - Field Emission Type X-ray and UV Hybrid Source Device - Google Patents

Abstract

A combined X-ray and ultraviolet light source device capable of selectively emitting X-rays and ultraviolet rays in a field emission method is provided. A combined X-ray and ultraviolet light source device according to the present invention includes a cathode electrode in which a plurality of emitters are arranged; a gate electrode for inducing electron emission from the emitter; a focusing electrode for controlling the degree of focusing the electron beam toward the center according to the driving signal; It is arranged to face the plurality of emitters with the internal space of a vacuum interposed therebetween, an X-ray target part is formed in the center of the base substrate, and a CL (Cathodoluminescence) type ultraviolet generating material is formed to surround the periphery of the X-ray target part. an X-ray-ultraviolet emitting substrate including an ultraviolet target portion formed thereon; and an anode electrode enclosing the outer portion of the X-ray-ultraviolet emitting substrate, sealingly bonded with a conductive brazing filler, and forming an electric field for accelerating the electron beam according to a driving signal; a driving signal for the anode electrode and It is configured to selectively emit X-rays or ultraviolet rays according to a driving signal for the focusing electrode.

Description

Field Emission Type X-ray and UV Hybrid Source Device

The present invention relates to a light source device that selectively or simultaneously emits X-rays and ultraviolet rays using an electron emission source of a field emission type, and can be used for medical or industrial purposes.

X-rays are used in the medical field for purposes such as diagnostic imaging or radiation therapy, and are used in various industrial fields such as non-destructive testing, material analysis, food testing, and ionizers. Ultraviolet (UV) is also widely used in the medical field, environment, and food industry through sterilization, disinfection, and photocuring action.

A thermoelectron emission type X-ray tube has been mainly used as an X-ray generator, and research and development of a field emission type X-ray source is in progress. In the field emission type X-ray source field, a cathode electrode having an emitter (electron emission source) composed of carbon nanotubes (CNT), a gate electrode inducing electron emission of the emitter, and a focusing electrode focusing the emitted electrons , and a quadrupole-type structure including an anode electrode having a target that emits X-rays by colliding with accelerated electrons, or a triode-type structure in which a focusing electrode is omitted here has been known. (See Patent Registration No. 10-0911434)

On the other hand, as a conventional ultraviolet light source, a low pressure mercury lamp has been frequently used. The low-pressure mercury lamp emits near-ultraviolet rays in the UV-C region of 254 nm. Ultraviolet rays in the UV-C region are so effective in sterilization that they are called germicidal rays, and low-pressure mercury lamps have been widely used. However, the use of mercury is restricted by the Restriction of Hazardous Substances Directive (RoHS), as it has a fatal adverse effect on the environment and human body when leaked. As an alternative to low-pressure mercury lamps, EL (Electroluminecence) UV LEDs have been proposed, but their use is limited due to their low output for sterilization. The technical limitations of the P-type semiconductor light emitting material in the PN junction structure are evaluated to be difficult to solve in a short period of time. As another alternative, an ultraviolet light emitting material and a light source capable of emitting ultraviolet rays in the UV-C band in a CL (Cathodoluminescence) method using the high energy of electrons by recent field emission and acceleration (refer to Korean Patent Publication No. 10-1482765) ) is known.

As described above, the fields of application of X-rays and ultraviolet rays are diverse, and there are parts that overlap each other in terms of the subject of use. However, these users have a burden of having to respectively provide an X-ray generator and an ultraviolet light source. This is because an X-ray source and an ultraviolet light source have not yet been commercialized as a single device.

Registered Patent Publication No. 10-0911434 Registered Patent Publication No. 10-1482765

An object of the present invention is to provide a combined X-ray and ultraviolet light source device capable of selectively or simultaneously emitting X-rays and ultraviolet rays in a field emission method. Another object of the present invention is to provide a configuration capable of improving durability and efficiency of a field emission type X-ray and ultraviolet light source device.

In order to solve the above problems, a combined X-ray and ultraviolet light source device according to the present invention includes a cathode electrode in which a plurality of emitters are arranged; a gate electrode for inducing electron emission from the emitter; a focusing electrode for controlling the degree of focusing the electron beam toward the center according to the driving signal; It is arranged to face the plurality of emitters with the internal space of a vacuum interposed therebetween, an X-ray target part is formed in the center of the base substrate, and a CL (Cathodoluminescence) type ultraviolet generating material is formed to surround the periphery of the X-ray target part. an X-ray-ultraviolet emitting substrate including an ultraviolet target portion formed thereon; and an anode electrode enclosing the outer portion of the X-ray-ultraviolet emitting substrate, sealingly bonded with a conductive brazing filler, and forming an electric field for accelerating the electron beam according to a driving signal; a driving signal for the anode electrode and It is configured to selectively emit X-rays or ultraviolet rays according to a driving signal for the focusing electrode.

A combined X-ray and ultraviolet light source device according to the present invention includes: a mode selection unit providing an X-ray mode for driving to emit X-rays from the X-ray target unit and an ultraviolet mode for driving to emit ultraviolet rays from the UV target unit; and a driving unit configured to differently apply a driving signal to the anode electrode or a driving signal to the focusing electrode according to the user's mode selection.

Here, the driver may apply a higher level driving signal to the focusing electrode than in the ultraviolet mode to focus the electron beam to the X-ray target unit in the X-ray mode.

In addition, the driver may apply a higher level driving signal to the anode electrode in the X-ray mode than in the ultraviolet mode.

The base substrate may be selected from a sapphire substrate, a quartz substrate, and a glass substrate to transmit X-rays and ultraviolet rays.

The UV target unit may include: an UV generation layer formed on the base substrate side; and a reflective layer formed on the surface side in contact with the inner space.

The base substrate may be a sapphire substrate, and the UV-generating layer may be an epitaxial layer formed on a surface of the sapphire substrate using a UV-generating material selected from the group consisting of AlN, GaN, AlGaN, and InGaN.

In addition, the reflective layer is a _{material selected from the group consisting of Al, HfO 2} , ZrO ₂ , Al ₂ O ₃ , TiO ₂ , Ti ₂ O ₃ , and SiO ₂ on the surface of the UV generating layer is deposited to a thickness of several nanometers. can be formed.

On the other hand, the anode electrode, the first cylindrical portion in contact with the upper ceramic spacer disposed between the focusing electrode; and a second cylindrical portion in contact with the X-ray-UV emitting substrate, wherein an inner diameter of the second cylindrical portion is greater than an inner diameter of the first cylindrical portion.

In addition, the anode electrode may include: a substrate support portion formed on the second cylindrical portion and in contact with an outer portion of a lower surface of the X-ray-ultraviolet emitting substrate; and a rim portion surrounding a periphery of the X-ray-ultraviolet ray emitting substrate.

A combined light source device according to an aspect of the present invention includes a cathode electrode in which a plurality of emitters are arranged; a gate electrode for inducing electron emission from the emitter; a focusing electrode for controlling the degree of focusing the electron beam toward the center according to the driving signal; It is disposed to face the plurality of emitters with an internal space of vacuum interposed therebetween, a first wavelength region light emitting target portion is formed in the center of a base substrate, and a second wavelength region light emitting target portion surrounds the periphery of the first wavelength light emission target portion. a multi-area light emitting substrate on which an area light emitting target portion is formed; and an anode electrode enclosing an outer portion of the multi-region light emitting substrate, sealingly bonded with a conductive brazing filler, and forming an electric field for accelerating the electron beam according to a driving signal; and selectively emitting light of the first wavelength region or the second wavelength region according to a driving signal for the focusing electrode.

The combined light source device may include: a mode selector configured to provide a first wavelength region light emission mode and a second wavelength region light emission mode; and a driving unit configured to differently apply a driving signal to the anode electrode or a driving signal to the focusing electrode according to the user's mode selection.

According to the present invention, a combined X-ray and ultraviolet light source device capable of selectively or simultaneously emitting X-rays and ultraviolet rays in a field emission method is provided. In addition, according to the configuration of the present invention, there is an effect of improving the durability and efficiency of the field emission type X-ray and ultraviolet light source device.

1 is a cross-sectional view of an X-ray and ultraviolet light source device having a quadrupole structure according to an embodiment of the present invention.
2 is a cross-sectional view of an X-ray and ultraviolet light source device having a tripolar structure according to an embodiment of the present invention.
3 shows an X-ray-ultraviolet ray emitting substrate according to an embodiment of the present invention.
4 is an X-ray-ultraviolet ray emitting substrate according to an embodiment of the present invention showing a bonded portion with the anode electrode.
5 shows an ultraviolet emission principle of an X-ray-ultraviolet ray emitting substrate according to an embodiment of the present invention.
6 shows a configuration for controlling and driving an X-ray and ultraviolet light source device according to an embodiment of the present invention.
FIG. 7 schematically shows the intensity of each driving signal in the ultraviolet mode, the X-ray mode, and the dual mode and an operation mode accordingly.

Hereinafter, various embodiments of the present invention will be described with reference to the drawings. The technical spirit of the present invention may be more clearly understood through the embodiments. In addition, the present invention is not limited to the embodiments described below, but may be modified in various forms within the scope of its technical spirit.

1 is a cross-sectional view of an X-ray and ultraviolet light source device having a quadrupole structure according to an embodiment of the present invention.

The four electrodes constituting the quadrupole type X-ray and ultraviolet light source device according to the present embodiment are viewed from the bottom of the drawing for convenience, a cathode electrode 10, a gate electrode 20, a focusing electrode 30, and an anode electrode ( 50) is made. A tube-shaped ceramic spacer 41 is formed between the cathode electrode 10 and the gate electrode 20 , between the gate electrode 20 and the focusing electrode 30 , and between the focusing electrode 30 and the anode electrode 50 . , 42, 43) are arranged. The ceramic spacers 41 , 42 , and 43 form an internal space and electrically insulate the electrode from the ceramic spacers. The ceramic spacers 41 , 42 , and 43 may be made of a material capable of ensuring airtightness and insulation, such as _{, for example, alumina (Al 2} O _{3 ) ceramics.}

A plurality of emitters 15 are arranged on the cathode electrode 10 . The plurality of emitters 15 may be arranged in several clusters on the upper surface of the cathode electrode 10 as shown. The plurality of emitters 15 may include, for example, carbon nanotubes (CNTs), but are not limited thereto, and may be formed of materials such as boron nitride nanotubes (BNTs), metals or silicon. may be

The gate electrode 20 includes a mesh portion 25 disposed close to the plurality of emitters 15 to form an electric field that initiates electron emission according to an input signal. The mesh portion 25 includes a plurality of gate holes through which the electron beam can pass. Meanwhile, the gate electrode 20 may include a first focusing section 22 extending in a cylindrical shape along the traveling direction of the electron beam to form an electric field focusing the electron beam toward the center thereof. The gate electrode 20 is insulated from the cathode electrode 10 by a lower ceramic spacer 41 .

The focusing electrode 30 extends between the gate electrode 20 and the anode electrode 50 in a cylindrical shape along the traveling direction of the electron beam to form a second focusing section ( 32). The focusing electrode 30 is insulated from the gate electrode 20 by an intermediate ceramic spacer 42 , and insulated from the anode electrode 50 by an upper ceramic spacer 43 , and is partially insulated for application of a driving voltage. is exposed to the outside. The focusing electrode 30 may have a different degree of focusing the electron beam according to the applied driving voltage.

The anode electrode 50 is disposed on an upper end of the upper ceramic spacer 43 , and the X-ray-ultraviolet ray emitting substrate 60 is seated thereon and bonded thereto. The anode electrode 50 includes a substrate support 53 in contact with an edge portion of a lower surface (lower surface in the drawing) of the X-ray-ultraviolet ray emitting substrate 60 and a rim surrounding the periphery of the X-ray-ultraviolet emitting substrate 60 . (Rim) section 54 is included. Here, the lower surface of the X-ray-ultraviolet emitting substrate 60 refers to the inner surface of the light source device on which the electron beam collides.

Meanwhile, the anode electrode 50 includes a first cylindrical portion 51 in contact with the upper ceramic spacer 43 and a second cylindrical portion 52 in contact with the X-ray-UV emitting substrate 60 , The inner diameter of the second cylindrical portion 52 may be formed to have a larger value than the inner diameter of the first cylindrical portion 51 . In addition, the X-ray-ultraviolet ray emitting substrate 60 may be formed to have a larger diameter than the inner diameter of the second cylindrical portion 52 . Through this structure, the area of the ultraviolet ray emission region Ru of the X-ray-ultraviolet emitting substrate 60 may be expanded. In addition, since the outer surface area of the anode 50 is increased due to the expansion of the outer diameter and the formation of the stepped portion according to the expansion of the inner diameter of the second cylindrical portion 52 , a more advantageous effect can be obtained for heat dissipation.

The X-ray-ultraviolet emitting substrate 60 includes a base substrate having light-transmitting properties for both X-rays and ultraviolet rays, and the X-ray emission region Rx ₁ provided in the central portion thereof and the UV emission region surrounding the X-ray emission region Rx _{1 ).} region Ru. The X-ray emission region Rx ₁ includes an X-ray target part 65 provided on a lower surface of the base substrate.

The anode electrode 50 may be formed of an alloy material such as Kovar, Invar, stainless steel (STS), or a metal material having a low coefficient of thermal expansion and excellent thermal conductivity, such as oxygen-free copper (OFC). have. A sapphire substrate may be used as a base substrate of the X-ray-ultraviolet ray emitting substrate 60 . The vacuum bonding technique of Korean Patent Registration No. 10-1898122 may be applied to bonding the anode electrode 50 and the X-ray-UV emitting substrate 60 using a sapphire substrate as a base substrate.

Through the above configuration, the quadrupole type X-ray and ultraviolet light source device according to the present embodiment is accelerated by a high acceleration voltage applied to the anode electrode 50 and the X-ray-ultraviolet ray emitting substrate 60. The electron beam proceeds toward the substrate 60 When the gate electrode 20 and the voltage applied to the focusing electrode 30 focus to the center and intensively collide with the X-ray target part 65 , the X-rays are emitted from the X-ray emission region Rx ₁ to the outside. emits In addition, when a relatively lower accelerating voltage is applied to the anode electrode 50 than when the above-described X-ray is emitted, and the electron beam collides with the X-ray-UV emitting substrate 60 without being focused, the ultraviolet emission region Ru It emits ultraviolet light to the outside. For this purpose, the configuration of the X-ray-ultraviolet emitting substrate 60 and control of driving signals will be described in more detail later.

2 is a cross-sectional view of an X-ray and ultraviolet light source device having a tripolar structure according to an embodiment of the present invention.

The three electrodes constituting the tripole type X-ray and ultraviolet light source device according to the present embodiment, when viewed from the bottom of the drawing for convenience, include a cathode electrode 10 , a gate electrode 20 , and an anode electrode 50 . It is distinguished from the embodiment of FIG. 1 in that there is no focusing electrode. Tube-shaped ceramic spacers 41 and 44 are disposed between the cathode electrode 10 and the gate electrode 20 and between the gate electrode 20 and the anode electrode 50 . The ceramic spacers 41 and 44 form an inner space and electrically insulate the electrode from the ceramic spacers. A plurality of emitters 15 are arranged on the cathode electrode 10 . Materials of the ceramic spacers 41 and 44 and the plurality of emitters 15 are the same as those described in the previous embodiment.

The gate electrode 20 includes a mesh portion 25 disposed close to the plurality of emitters 15 to form an electric field that initiates electron emission according to an input signal. The mesh portion 25 includes a plurality of gate holes through which the electron beam can pass. Meanwhile, the gate electrode 20 includes a first focusing section 22 that extends in a cylindrical shape along the traveling direction of the electron beam and forms an electric field that focuses the electron beam toward the center thereof. The gate electrode 20 is insulated from the cathode electrode 10 by a lower ceramic spacer 41 and insulated from the anode electrode 50 by an upper ceramic spacer 44 .

The shape and material of the anode electrode 50 are the same as those described in the previous embodiment. Matters regarding the X-ray-UV emitting substrate 60 seated on the anode electrode 50 are also the same as described above. However, in the present embodiment, the diameter of the X-ray target part 65 formed on the X-ray-ultraviolet emitting substrate 60 may be formed to be larger than that of the embodiment of FIG. 1 . As a result, the diameter of the X-ray emission region Rx _{2 also becomes larger.}

The tripole type X-ray and ultraviolet light source device according to the present embodiment is advantageous in miniaturization and has advantages in that the driving circuit can be simplified because there is no focusing electrode. However, since the focusing of the electron beam depends on the first focusing section 22 formed in the gate electrode 20 , the size of the emission focal point when X-rays are emitted may be relatively larger than that of the quadrupole type. Although this characteristic may be a disadvantage for taking a diagnostic image, it may provide a sufficient effect for applications such as static electricity removal.

3 shows an X-ray-ultraviolet ray emitting substrate according to an embodiment of the present invention.

The X-ray-ultraviolet emitting substrate 60 according to the present embodiment is an example of a multi-region light emitting substrate. The base substrate 61 and the base substrate 61 are formed on one surface, and the base substrate 61 is located at the center thereof. ) an X-ray target part 65 formed to have a predetermined diameter smaller than the diameter of the X-ray target part 65 , and an ultraviolet target part 62 formed outside the X-ray target part 65 . The UV target part 62 may have an outer diameter that is slightly smaller than or the same as the diameter of the base substrate 61 . Here, the X-ray target unit 65 corresponds to an example of a first wavelength region light emitting target unit, and the ultraviolet target unit 62 corresponds to an example of a second wavelength region light emitting target unit.

The base substrate 61 is preferably a sapphire substrate. The sapphire substrate can transmit not only X-rays but also ultraviolet rays, and shows suitable properties for depositing the X-ray target portion 65 including a metal material and the ultraviolet light target portion 62 including an ultraviolet light emitting material on the surface thereof. . A beryllium (Be) substrate is mainly used as the X-ray emission window, but the sapphire substrate is more suitable because it is more economical than the beryllium substrate and has excellent UV transmittance. However, as another embodiment, a quartz substrate or a soda-lime glass substrate may be applied to the base substrate 61 . Meanwhile, the base substrate 61 is preferably circular.

The X-ray target part 65 may be formed by depositing an X-ray target material through a PVD or CVD process using a metal mask that exposes only the central portion on one surface of the base substrate 61 . Applicable X-ray target materials include Cr, Fe, Co, Cu, Mo, Ag, W, W+Re, and the like. The atomic number, excitation voltage, and characteristic X-ray wavelength of each of the X-ray target materials are summarized in Table 1 below. The X-ray target material constituting the X-ray target unit 65 may be selected from among those listed in Table 1 below, suitable for the main use of X-rays emitted from the combined X-ray and ultraviolet light source device according to the present invention.

x-ray target material atomic number Excitation voltage (kV) Wavelength (nm) Cr 24 5.98 20.85 Fe 26 7.10 17.57 Co 27 7.71 16.21 Cu 29 8.86 13.80 Mo 42 20.0 6.20 Ag 47 25.5 4.86 W 74 69.3 1.78

Meanwhile, the UV target unit 62 may include an UV generating layer 621 disposed on the base substrate 61 side and a reflective layer 622 disposed on the surface side. The ultraviolet generating layer 621 is excited by the collision of electron beams in a cathodoluminecence (CL) method and then stabilized. The ultraviolet generation layer 621 emits light in the ultraviolet wavelength band, more preferably in the UV-C wavelength band. It may be formed by including the material. The ultraviolet generating material may include AlN, GaN, AlGaN, InGaN (Al _x Ga _{1 - x} N-based/<364 nm), ZnS, MgS, MgSe, CaS, and the like. Among these, materials such as AlN, GaN, AlGaN, and InGaN (Al _x Ga _{1 - x} N-based/<364 nm) have a lattice constant close to that of sapphire, so that the base substrate 61 is epitaxial to the surface of the sapphire substrate. It is also suitable for forming an epitaxial layer. In particular, AlGaN can control the band gap from 3.4 eV (~360 nm) to 6.2 eV (~ 200 nm) depending on the quantum well structure, and it is also possible to form a multi-quantum well structure. Therefore, it is also possible to implement UV-A, UV-B, UV-C light emission in all areas.

A reflective layer 622 may be provided on the surface side of the ultraviolet generating layer 621 . The reflective layer 622 reflects the UV rays generated by the UV generation layer 621 toward the inside of the light source device so that they are emitted to the outside, thereby improving luminous efficiency. The reflective layer 622 may be formed by depositing a material such as _{Al, HfO 2} , ZrO ₂ , Al ₂ O ₃ , TiO ₂ , Ti ₂ O ₃ , SiO _{2 to a thickness of several nm.} The ultraviolet generating layer 621 and the reflective layer 622 may also be formed in an outer region of the X-ray target unit 65 through a deposition process using a metal mask, similarly to the above-described X-ray target unit 65 .

Meanwhile, a conductive wiring 66 connecting from one outer periphery of the UV target part 62 to the X-ray target part 65 may be provided. The conductive wiring 66 may be formed simultaneously with the X-ray target part 62 using the above-described X-ray target material. The conductive wiring 66 may be formed of a transparent electrode material that is transparent to ultraviolet rays.

The UV target part 62 is made of a semiconductor material, and the brazing filler bonding between the anode electrode 50 (refer to FIGS. 1 and 2) and the base substrate 61 and the UV target part 62 is electrically conductive. Therefore, when a driving voltage is applied to the anode electrode 50, a high potential according to the driving voltage is formed in the entire X-ray-ultraviolet emitting substrate 60, and the X-ray-ultraviolet emitting substrate 60 and the cathode electrode ( 10 (refer to FIGS. 1 and 2), an electric field for electron beam acceleration is formed. When a high tube current value is required for emitting X-rays, it is advantageous to provide a conductive wiring 66 that crosses the UV target portion 62 .

4 is an X-ray-ultraviolet ray emitting substrate according to an embodiment of the present invention showing a bonded portion with the anode electrode.

As shown, when the outer diameter of the ultraviolet target part 62 is formed to be slightly smaller than the diameter of the base substrate 61, the X-ray-brazing filler bonding the ultraviolet ray emitting substrate 60 and the anode electrode 50 is the ultraviolet ray. It fills not only between the inner surface of the target part 62 and the above-described substrate support part 53 , but also between the outer peripheral surface of the ultraviolet target part 62 and the rim part 54 . Such a bonding structure is advantageous for maintaining the internal space of the light source device in a high vacuum state, and has an advantageous aspect in smooth conduction of electricity and heat between the anode electrode 50 and the X-ray-ultraviolet ray emitting substrate 60 . The brazing filler is mainly composed of Al, Cu, Ag-based materials, and thus has excellent electrical conductivity and thermal conductivity.

On the other hand, when the above-described reflective layer 622 is formed of a metal material, an effect of metalizing the surface of the X-ray-ultraviolet emitting substrate 60 using a sapphire substrate as a base substrate can be obtained, and the X-ray-ultraviolet emitting substrate 60 . It is possible to improve the stability of the junction between the anode and the anode 50, that is, airtightness, bonding strength, durability, and the like.

5 shows an ultraviolet emission principle of an X-ray-ultraviolet ray emitting substrate according to an embodiment of the present invention.

When driven in the ultraviolet emission mode, electrons accelerated by the driving voltage applied to the anode electrode collide with the ultraviolet target portion 62 (refer to FIGS. 3 and 4), and the ultraviolet generating material of the ultraviolet generation layer 621 causes electrons UV rays are emitted by the collision energy of Some of the emitted ultraviolet rays pass through the base substrate and are emitted to the outside as they are, and the remaining part facing the base substrate is also reflected by the reflective layer 622 and emitted to the outside again.

6 shows a configuration for controlling and driving an X-ray and ultraviolet light source device according to an embodiment of the present invention.

The combined X-ray and ultraviolet light source device according to the present invention implements the light source module 100 and selective driving of the X-ray mode and the ultraviolet mode of the light source module 100, or dual, which is an X-ray-ultraviolet light emission mode It may further include a controller 110 , a mode selector 120 , and a driver 130 for selectively driving three modes including the mode. The mode selection unit 120 is configured to include a user input means. The mode selector 120 provides at least an option of an X-ray mode and an ultraviolet mode, as examples of the first wavelength region light emitting mode and the second wavelength region light emitting mode, and includes an X-ray mode, an ultraviolet light mode, and a dual mode. can be configured to provide. The control unit 110 controls the driving unit 130 according to the selection result received from the mode selection unit 120 .

The driving unit 130 provides a driving signal V suitable for each of the anode electrode 50 , the cathode electrode 10 , the gate electrode 20 , and the focusing electrode 30 of the light source module 100 according to the user's mode selection. _A ,V _C ,V _G ,V _{F )} are provided. The embodiment shown in this figure relates to a quadrupole type light source module 100 provided with a focusing electrode 30 . In the case of a triode type light source module without a focusing electrode, the driver also implements the aforementioned X-ray mode, ultraviolet mode, and dual mode only _{with driving signals (VA,V C} ,V _{G ) applied to the anode electrode, the cathode electrode, and the gate electrode.} can be configured to

FIG. 7 schematically shows the intensity of each driving signal in the ultraviolet mode, the X-ray mode, and the dual mode and an operation mode accordingly.

Hereinafter, a driving signal for each mode and an operation aspect will be described in more detail with reference to FIGS. 6 and 7 together. In FIG. 7 , _{for example, when the potential of the driving signal V C applied to the cathode 10 is the ground potential, the driving signal V G} of the gate electrode 20 and the driving signal of the focusing electrode 30 . (V _F ) and the potential of the driving signal (V _A ) of the anode electrode 50 are expressed as a '+' sign according to a relative difference with respect to the driving signal (V _{C ) of the cathode electrode 10 .} The relative difference between the drive signals is important, and the absolute potential of the drive signals can vary. _{For example, the driving signal V A} applied to the anode electrode 50 may be a ground potential, and driving signals applied to the other electrodes may be configured as a negative potential.

First, looking at the UV mode, when the cathode electrode 10 driving signal V _C is at the ground potential, a gate driving signal V _G of several hundred V to several kV is applied to the gate electrode 20 . and the anode driving signal V _AU of several kV level may be applied to the anode electrode 50 . _{In this case, the driving signal V FU} of the same level as the gate driving signal V _G may be applied to the focusing electrode 30 or may be floated. As a result, the electron beam emitted from the emitter on the cathode electrode 10 is not focused, or is focused only enough to reach the above-described X-ray-ultraviolet ray emitting substrate. The colliding electron beam causes cathode-luminescence (CL) light emission from the above-described ultraviolet target portion to emit ultraviolet light to the outside of the light source module 100 .

Looking at the X-ray mode, when the cathode electrode 10 driving signal V _C is at the ground potential, a gate driving signal V _G of several hundred V to several kV is applied to the gate electrode 20 . _{and the anode driving signal V AX} of several to several tens of kV may be applied to the anode electrode 50 . For example, when X-rays are emitted for imaging a medical X-ray diagnostic image, a signal of about 65 kV may be applied as _{the anode driving signal V AX .} The potential difference between the anode driving signal V _AX and the cathode driving signal V _C may vary depending on the use of X-rays. When soft X-rays are required, a signal with a lower voltage than the above example is applied.

The voltage level of the anode driving signal V _AX of the X-ray mode is higher than that of the anode driving signal V _{AU of the ultraviolet mode.} This is because a bandgap energy higher than that of UV emission is required for X-ray emission. Meanwhile, in the X-ray mode, the focusing electrode driving signal V _{FX having a higher level than the gate driving signal V G} and lower than the anode driving signal V _AX is applied to the focusing electrode 30 . The electron beam passing through the inner section of the focusing electrode 30 is focused toward the center thereof, collides with the X-ray target portion formed in the center of the aforementioned X-ray-ultraviolet emitting substrate, and as a result, X-rays are emitted. Here, the focusing electrode driving signal V _{FX in the} X-ray mode is higher than the focusing electrode driving signal V _{FU in the aforementioned ultraviolet mode.}

In the dual mode, since X-ray emission is required, the anode driving signal V _{A is applied at the same level as the anode driving signal V AX} of the X-ray mode, and the X-rays are applied to the focusing electrode 30 so that UV rays can be emitted at the same time. _{By applying the driving signal V F} of a lower level than the focusing electrode driving signal V _FX of the mode, the electron beam may collide with the X-ray target unit and the UV target unit at the same time.

10: cathode electrode
20: gate electrode
30: focusing electrode
41-44: ceramic spacer
50: anode electrode
60: X-ray-ultraviolet emitting substrate
61: base substrate
62: UV target unit
65: X-ray target unit

Claims (12)

a cathode electrode in which a plurality of emitters are arranged;
a gate electrode for inducing electron emission from the emitter;
a focusing electrode for controlling the degree of focusing the electron beam toward the center according to the driving signal;
It is arranged to face the plurality of emitters with the internal space of a vacuum interposed therebetween, an X-ray target part is formed in the center of the base substrate, and a CL (Cathodoluminescence) type ultraviolet generating material is formed around the X-ray target part. an X-ray-ultraviolet emitting substrate including an ultraviolet target portion formed thereon;
an anode electrode enclosing an outer portion of the X-ray-ultraviolet emitting substrate, sealingly bonded with a conductive brazing filler, and forming an electric field for accelerating the electron beam according to a driving signal;
a mode selection unit providing an X-ray mode for driving to emit X-rays from the X-ray target unit and an ultraviolet mode for driving to emit ultraviolet rays from the UV target unit; and
Including; a driving unit that differently applies a driving signal to the anode electrode or a driving signal to the focusing electrode according to the user's mode selection;
The driving unit applies a driving signal of a higher level than a driving signal in the ultraviolet mode to the focusing electrode in the X-ray mode to focus the electron beam to the X-ray target unit. delete delete According to claim 1,
The driving unit applies a higher level driving signal to the anode electrode in the X-ray mode than when in the ultraviolet mode,
X-ray and UV light source device. According to claim 1,
The base substrate is selected from a sapphire substrate, a quartz substrate, and a glass substrate to transmit X-rays and ultraviolet rays,
X-ray and UV light source device. According to claim 1,
The UV target unit,
an ultraviolet generating layer formed on the side of the base substrate; and
Containing; a reflective layer formed on the surface side in contact with the inner space
X-ray and UV light source device. 7. The method of claim 6,
The base substrate is a sapphire substrate,
The UV-generating layer is an epitaxial layer formed of a UV-generating material selected from the group consisting of AlN, GaN, AlGaN, and InGaN on the surface of the sapphire substrate,
X-ray and UV light source device. 7. The method of claim 6,
The reflective layer is formed by depositing a material selected from the group consisting _{of Al, HfO 2} , ZrO ₂ , Al ₂ O ₃ , TiO ₂ , Ti ₂ O ₃ , and SiO ₂ to a thickness of several nanometers on the surface of the ultraviolet generating layer,
X-ray and UV light source device. According to claim 1,
The anode electrode is
a first cylindrical portion in contact with an upper ceramic spacer disposed between the focusing electrode; and;
Including; a second cylindrical portion in contact with the X-ray-ultraviolet ray emitting substrate;
The inner diameter of the second cylindrical portion has a larger value than the inner diameter of the first cylindrical portion,
X-ray and UV light source device. 10. The method of claim 9,
The anode electrode is
a substrate support portion formed on the second cylindrical portion and in contact with an outer portion of a lower surface of the X-ray-ultraviolet emitting substrate; and
Further comprising; a rim (Rim) portion surrounding the periphery of the X-ray-emitting substrate,
X-ray and UV light source device. a cathode electrode in which a plurality of emitters are arranged;
a gate electrode for inducing electron emission from the emitter;
a focusing electrode for controlling the degree of focusing the electron beam toward the center according to the driving signal;
It is disposed to face the plurality of emitters with a vacuum internal space interposed therebetween, a first wavelength region light emitting target portion is formed in the center of the base substrate, and a second light emitting target portion is formed to surround the periphery of the first wavelength region light emitting target portion. a multi-region light emitting substrate on which a wavelength region light emitting target portion is formed;
an anode electrode enclosing an outer portion of the multi-region light emitting substrate, sealingly bonded with a conductive brazing filler, and forming an electric field for accelerating the electron beam according to a driving signal;
a mode selector providing a first wavelength region light emitting mode and a second wavelength region light emitting mode; and
Including; a driving unit that differently applies a driving signal to the anode electrode or a driving signal to the focusing electrode according to the user's mode selection;
In the first wavelength region light emitting mode, the driver applies a higher level driving signal to the focusing electrode than a driving signal in the second wavelength region light emitting mode to the first wavelength region light emitting target portion. to focus the electron beam,
Combined light source device.
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