Charged particle detection material, and charged particle detection film and charged particle detection liquid using the same

Abstract

A charged particle detection material which can detect charged particles due to a discharge phenomenon or the like caused even in a very low voltage which cannot be observed by a prior art, as well as a charged particle detection film and a charged particle detection liquid using the material. The charged particle detection material and the charged particle detection film contain at least one of a fluorescent substance, a luminescent substance, an electroluminescent substance, a fractoluminescent substance, a photochromic substance, an afterglow substance, a photostimulated luminescent substance and a mechanoluminescent substance and can easily detect emission or incidence of charged particles in real time.

Claims

1. A charged particle detection material for detecting charged particles with luminescence, comprising at least one of: an electroluminescent substance, a fractoluminescent substance, a photochromic substance, an afterglow substance, and a photostimulated luminescent substance; and phosphorescent luminescent materials selected from the group consisting of iridium complexes and platinum complexes, which emit light by X-rays, ultraviolet rays, or visible light, luminol, rofin, lucigenin, oxalate, photosensitive luminescent dye, and bioluminescent substances, wherein a total weight ratio of: the electroluminescent substance, the fractoluminescent substance, the photochromic substance, the afterglow substance, and the photostimulated luminescent substance, and the phosphorescent luminescent materials selected from the group consisting of iridium complexes and platinum complexes, which emit light by X-rays, ultraviolet rays, or visible light, luminol, rofin, lucigenin, oxalate, the photosensitive luminescent dye, and the bioluminescent substances is 20 to 80 wt %.

2. The charged particle detection material according to claim 1, wherein the afterglow substance is a substance represented by SrAl.sub.2O.sub.4 which is doped with Eu.sup.2+ and Dy.sup.3+, a substance represented by SrAl.sub.2O.sub.4 which is doped with Eu.sup.2+, Dy.sup.2+, and M (M=monovalent to trivalent metal ions), or a substance represented by Zn.sub.3(PO.sub.4).sub.2 which is doped with Mn.sup.2+ and M (M=monovalent to trivalent metal ions).

3. The charged particle detection material for detecting charged particles with luminescence according to claim 1, further comprising: at least a mechanoluminescent substance.

4. The charged particle detection material according to claim 3, wherein the mechanoluminescent substance is a substance represented by SrAl.sub.2O.sub.4 which is doped with Eu.sup.2+, a substance represented by SrAl.sub.2O.sub.4 which is doped with at least one of Eu.sup.2+, Ho.sup.3+, Dy.sup.2+, M.sub.1, M.sub.2, and M.sub.3 (M.sub.1, M.sub.2, M.sub.3=monovalent to trivalent metal ions different from each other), or a substance represented by CaYAl.sub.3O.sub.7 which is doped with Eu.sup.2+.

5. A charged particle detection system for detecting charged particles, comprising: a charged particle-emitting part; a charged particle incident part, and a charged particle detection material according to claim 1, wherein the charged particle detection material is between the charged particle emitting part and the charged particle incident part, and wherein an electric field therebetween is within a range of 1 to 3000 V/mm in air.

6. The charged particle detection system according to claim 5, wherein the afterglow substance is a substance represented by SrAl.sub.2O.sub.4 which is doped with Eu2+ and Dy.sup.3+, a substance represented by SrAl.sub.2O.sub.4 which is doped with Eu.sup.2+, Dy.sup.2+, and M (M=monovalent to trivalent metal ions), or a substance represented by Zn.sub.3(PO.sub.4).sub.2 which is doped with Mn2+ and M (M=monovalent to trivalent metal ions).

7. A detection film including a charged particle detection film and a charged particle detection material according to claim 1.

8. A detection film including a charged particle detection film and a charged particle detection material according to claim 3.

9. A detection liquid including a charged particle detection liquid and a charged particle detection material according to claim 1.

10. A detection liquid including a charged particle detection liquid and a charged particle detection material according to claim 3.

11. A charged particle detection system for detecting charged particles under air pressure, comprising: a charged particle-emitting part emitting charged particles; a charged particle detection material containing at least one of SrAl.sub.2O.sub.4:E.sup.2+, SrAl.sub.2O.sub.4:Ho.sup.3+, Ce.sup.3+, CaYAl.sub.3O.sub.7:Eu.sup.2+, SrAl.sub.2O.sub.4:Eu.sup.2+, Cr.sup.3+, Nd.sup.3+, SrAl.sub.2O.sub.4:Eu.sup.2+, Dy.sup.3+, methyl salicylate, and Eu(TTA)3phen; and a charged particle incident part, wherein between the charged particle-emitting part and the charged particle incident part is an electric field or a potential difference, the electric field between the charged particle-emitting part and the charged particle incident part being within a range of 1 to 3000 V/mm in air.

12. The charged particle detection system according to claim 11, wherein the charged particles comprise electrons, and wherein the potential difference between the charged particle-emitting part and the charged particle incident part is lower than a voltage V calculated by Paschen's law.

13. The charged particle detection system according to claim 11, wherein an air pressure is between the charged particle-emitting part and the charged particle incident part, and is in a range of 10.sup.−3 to 10.sup.5 Torr.

14. The charged particle detection system according to claim 11, wherein the charged particle detection material comprises a charged particle detection film.

15. The charged particle detection system according to claim 11, wherein the charged particle detection material comprises a charged particle detection liquid.

Description

BRIEF DESCRIPTION OF DRAWINGS

(1) FIG. 1 shows a schematic drawing of a charged particle detection system according to Embodiment 1.

(2) FIG. 2 shows a photograph of a luminescent part P2 formed on a surface of a charged particle incident part in Example 1.

(3) FIG. 3 shows a schematic drawing of the charged particle detection system at the time that a charged member is inserted between a charged particle-emitting part and the charged particle incident part in Example 1.

(4) FIG. 4 shows a photograph of a luminescent part P3 before the charged member is inserted between the charged particle-emitting part and the charged particle incident part in Example 1.

(5) FIG. 5 shows a photograph of the luminescent part P3 at the time that the charged member is inserted between the charged particle-emitting part and the charged particle incident part in Example 1.

(6) FIG. 6 shows a photograph of the luminescent part P3 at the time that the charged member inserted between the charged particle-emitting part and the charged particle incident part is pulled out in Example 1.

(7) FIG. 7 shows a photograph of a test result when using SrAl.sub.2O.sub.4:Ho.sup.3+, Ce.sup.3+ as the mechanoluminescent substance.

(8) FIG. 8 shows a photograph of a test result when using CaYAl.sub.3O.sub.7:Eu.sup.2+ as the mechanoluminescent substance.

(9) FIG. 9 shows a photograph of a test result when using SrAl.sub.2O.sub.4:Eu.sup.2+, Cr.sup.3+, Nd.sup.3+ as the mechanoluminescent substance.

(10) FIG. 10 shows a photograph of a test result when changing the polarity of the electrode in Example 1.

(11) FIG. 11 shows a photograph at the time that a human hand is moved while applying a voltage to a rod on which a charged particle detection film is formed in Example 2.

(12) FIG. 12 shows a photograph of a luminescent part formed on the surface of the charged particle incident part at the time that a voltage is applied on an electrode needle and the charged particles are made to enter the charged particle detection film in Example 3.

(13) FIG. 13 shows a photograph of the luminescent part formed on the surface of the charged particle incident part at the time that a voltage is applied to the electrode needle and the charged particles are made to enter the charged particle detection film in Example 4.

(14) FIG. 14 shows a photograph of the luminescent part formed on the surface of the charged particle incident part at the time that a voltage is applied to the electrode needle and the charged particles are made to enter the charged particle detection film in Example 5.

(15) FIG. 15 shows a photograph of the luminescent part formed on the surface of the charged particle incident part at the time that a voltage is applied to the electrode needle and the charged particles are made to enter the charged particle detection film in Example 6.

(16) FIG. 16 shows a photograph of the luminescent part formed on the surface of the charged particle incident part at the time that a voltage is applied to the electrode needle and the charged particles are made to enter the charged particle detection film in Example 7 (SrAl.sub.2O.sub.4:Eu.sup.2+, Dy.sup.3+).

(17) FIG. 17 shows a photograph of the luminescent part formed on the surface of the charged particle incident part at the time that a voltage is applied to the electrode needle and the charged particles are made to enter the charged particle detection film in Example 7 (β-Zn.sub.3(PO.sub.4).sub.2:Mn.sup.2+, Ga.sup.3+).

(18) FIG. 18 shows a photograph at the time that the charged particles are detected using a SrAl.sub.2O.sub.4:Eu.sup.2+ powder.

(19) FIG. 19 shows a photograph at the time that the charged particles are detected using a luminescent sheet in which a SrAl.sub.2O.sub.4:Eu.sup.2+ powder is dispersed.

(20) FIG. 20 shows a photograph at the time that the charged particle detection film containing SrAl.sub.2O.sub.4:Eu.sup.2+ is formed on an aluminum foil, to which the charged particles are made to enter.

(21) FIG. 21 shows a photograph at the time that the charged particles are made to enter a paper nonwoven fabric in which the charged particle detection material is dispersed.

(22) FIG. 22 shows a photograph at the time that the charged particles are made to enter a liquid mixture of SrAl.sub.2O.sub.4:Eu.sup.2+ and photocurable acryl.

(23) FIG. 23 shows a photograph at the time that a surface of the liquid mixture of SrAl.sub.2O.sub.4:Eu.sup.2+ and photocurable acryl is cured, and then the charged particles are made to enter the surface.

DESCRIPTION OF EMBODIMENTS

(24) A charged particle detection material according to the present invention detects emission of charged particles from a charged particle-emitting part or incidence of charged particles to a charged particle incident part.

(25) Herein, the charged particle-emitting part and the charged particle incident part are not particularly limited as long as the charged particles can be emitted from or can enter a surface, respectively, when applying an electric field between the charged particle-emitting part and the charged particle incident part by applying voltages to them. Typical examples of substances constituting the charged particle-emitting part and the charged particle incident part include, but are not limited to: a conductor like a metal having a high electric conductivity such as tungsten, stainless steel, gold, silver and copper; a semiconductor such as silicon: and an insulator such as ceramics, polymer and resin. For example, when the charged particles are electrons, the charged particle-emitting part can be exemplified by aluminum or the like, and the charged particle incident part can be exemplified by vinyl chloride or the like.

(26) Embodiments of ad charged particle detection system using a charged particle detection material according to the present invention will be explained below with reference to the accompanying drawings. Note that the present invention is not limited to the following embodiments.

Embodiment 1

(27) A configuration will be explained, in which a charged particle detection film including a charged particle detection material containing at least one of a fluorescent substance, a luminescent substance, an electroluminescent substance, a fractoluminescent substance, a photochromic substance, a afterglow substance, a photostimulated luminescent substance and a mechanoluminescent substance is formed on surfaces of a charged particle-emitting part and a charged particle incident part, and when an electric field is applied between the charged particle-emitting part and the charged particle incident part, charged particles (e.g. N.sup.+, N.sup.−, electrons, etc.) caused by ionizing a gas around the electrode are emitted from the charged particle-emitting part and enter the charged particle incident part.

(28) FIG. 1 shows a schematic drawing of a charged particle detection system 1 according to this embodiment. As shown in this figure, the charged particle detection system 1 according to the present embodiment is composed of a cylindrical charged particle-emitting part 10 having a lower end formed in a hemispherical shape, a rectangular plate-shaped charged particle incident part 20 disposed below the cylindrical charged particle-emitting part 10, and DC high-voltage generators (not shown in figure) respectively connected to the cylindrical charged particle-emitting part 10 and the rectangular plate-shaped charged particle incident part 20. Note that the cylindrical charged particle-emitting part 10 and the rectangular plate-shaped charged particle incident part 20 are fixed by jigs not shown in figure. In addition, the shape of the cylindrical charged particle-emitting part 10 is not particularly limited, and its end may be spherical, needle-shaped or planar.

(29) A charged particle detection film 21 including a charged particle detection material containing a substance such as the above-described fluorescent substance is provided on the upper surface of the rectangular plate-shaped charged particle incident part 20 disposed below the cylindrical charged particle-emitting part 10.

(30) Herein, the charged particle detection film 21 provided on the surface of the rectangular plate-shaped charged particle incident part 20 is not particularly limited as long as it includes the charged particle detection material containing at least one of the above-described substances. The charged particle detection film 21 may be prepared by homogeneously mixing e.g. an epoxy resin or an urethane resin, a curing agent and a solvent for controlling crosslinking/curing reaction of these resins, the above-described substances, and a dispersant/adjuvant for homogeneously dispersing the substances, and applying/curing this mixture on the surface of the rectangular plate-shaped charged particle incident part 20. The concentration (weight ratio) of the above-described substances contained in the charged particle detection film 21 is not particularly limited, but a range of 20 to 80 wt % is preferable because light emission can be visually confirmed, and a range of 50 to 70 wt % is more preferable because light emission can be visually confirmed more obviously.

(31) The DC high-voltage generator is not particularly limited as long as it can apply a predetermined electric field (generate a potential difference) between the cylindrical charged particle-emitting part 10 and the rectangular plate-shaped charged particle incident part 20, and a commercial product may be used. The intensity of the electric field between the cylindrical charged particle-emitting part 10 and the rectangular plate-shaped charged particle incident part 20 is also not particularly limited, but a range of 1 to 3000 V/mm is preferable because low-energy charged particles which have been unobservable by the conventional observation method can be easily detected in real time, and a range of 22 to 1000 V/mm is more preferable because the low-energy charged particles can be more easily detected.

Example 1

(32) Stainless steel was used as the cylindrical charged particle-emitting part 10, an aluminum foil was used as the rectangular plate-shaped charged particle incident part 20, and a mixture of a mechanoluminescent substance SrAl.sub.2O.sub.4:Eu.sup.2+ and photocurable acrylic resin (made by MICROJET Corporation) (weight ratio of SrAl.sub.2O.sub.4:Eu.sup.2+ is 70%) was applied and cured to use it as a charged particle detection film 21 (about 100 μm in thickness) formed on the surface of the rectangular plate-shaped charged particle incident part 20. The DC high-voltage generator was operated in air at 1 atm. humidity of 30% and temperature of 10° C. so as to apply an electric field (100 to 800 V/mm) between the cylindrical charged particle-emitting part 10 and the rectangular plate-shaped charged particle incident part 20 (10 mm). The result is shown in FIG. 2.

(33) As shown in FIG. 2, when the electric field is applied between the cylindrical charged particle-emitting part 10 and the rectangular plate-shaped charged particle incident part 20, a substantially circular luminescent part P2 with a center O beneath the cylindrical charged particle-emitting part 10 is formed on the upper surface of the rectangular plate-shaped charged particle incident part 20. For the circular luminescent part P2, the center O emits light at first, and when continuing to inject the charged particles into the rectangular plate-shaped charged particle incident part 20, the circular luminescent part P2 spreads outwardly from the center O over time, and the luminance around the center O is decreased. That is, although the center O emits light at first, the circular luminescent part P2 becomes ring-shaped over time, and the diameter of the ring shape seems to increase. In FIG. 2, the luminance is highest at the outermost portion and gradually decreases toward the center O. In addition, a radius of the circular luminescent part P2 is small at first when activating the DC high-voltage generator, but increases over time.

(34) It was confirmed that the same experiment in air at 1 atm 80% humidity and 80° C. resulted in light emission in a similar manner. Furthermore, it was confirmed that the same experiment in a state where the pressure inside the container housing the cylindrical charged particle-emitting part 10 and the rectangular plate-shaped charged particle incident part 20 was reduced to 10.sup.−3 Torr by a rotary pump resulted in light emission in a similar manner.

(35) Next, as shown in FIG. 3, a charged member 30 composed of a rod-shaped aluminum foil in a floating state was inserted between the cylindrical charged particle-emitting part 10 and the rectangular plate-shaped charged particle incident part 20. The result is shown in FIG. 4.

(36) It was found that a luminescent part P3 was located under the rod shaped aluminum foil before inserting the charged member 30 as shown in FIG. 4, but the luminescent part P3 moved toward the charged member 30 (upward) after inserting the charged member 30 as shown in FIG. 5. In addition, an ammeter was provided between the cylindrical charged particle-emitting part 10 and the rectangular plate-shaped charged particle incident part 20, a current therebetween was measured at this time, and as a result, it was found that the current flowed from the rectangular plate-shaped charged particle incident part 20 to the cylindrical charged particle-emitting part 10.

(37) Note that it was found that when the charged member 30 was pulled from between the cylindrical charged particle-emitting part 10 and the rectangular plate-shaped charged particle incident part 20, the luminescent part P3 returned to the position before inserting the charged member 30 as shown in FIG. 6.

(38) From the above, it was found that the negatively-charged particles moved from the cylindrical charged particle-emitting part 10 toward the rectangular plate-shaped charged particle incident part 20. Herein, the movement of the charged particles is considered to include not only a phenomenon that specific charged particles such as N and electrons directly move from the cylindrical charged particle-emitting part 10 to the rectangular plate-shaped charged particle incident part 20, but also a phenomenon that some charged particles continuously push other charged particles like a chain-reaction collision, and as a result, the charged particles seem to move from the cylindrical charged particle-emitting part 10 to the rectangular plate-shaped charged particle incident part 20. Furthermore, it is considered that the movement also includes a phenomenon that the gas molecules around the cylindrical charged particle-emitting part 10 are ionized and move to the rectangular plate-shaped charged particle incident part 20 so that the charged particles seem to move from the cylindrical charged particle-emitting part 10 to the rectangular plate-shaped charged particle incident part 20, is also included.

(39) Charged particle detection films 21 respectively containing similar mechanoluminescent substances SrAl.sub.2O.sub.4:Ho.sup.3+, Ce.sup.3+; CaYAl.sub.3O.sub.7:Eu.sup.2+; or SrAl.sub.2O.sub.4:Eu.sup.2+, Cr.sup.3+, Nd.sup.3+ instead of SrAl.sub.2O.sub.4:Eu.sup.2+ were prepared, and subjected to the same test. The test results are shown in FIGS. 7 to 9. As can be seen from these figures, when the charged particles are made to enter the charged particle detection film 21, the luminescent part P was formed on each charged particle detection film 21. Therefore it was found that the charged particles could be detected also when using the charged particle detection films 21 including these charged particle detection materials.

(40) Furthermore, a test result when changing the polarity of the electrode in Example 1 is shown in FIG. 10. As shown in FIG. 10, it was found that the charged particles could be detected even when changing the polarity of the electrode (i.e., even when charged particles with different polarities entered the film).

Example 2

(41) In Example 1, the charged particle detection film including the charged particle detection material was formed on the surface of the charged particle incident part, but the present invention is not limited thereto. In this example, the same charged particle detection film (about 100 μm in thickness) as the charged particle detection film used in Example 1 was formed on a surface of a cylindrical rod made of stainless steel. Then, a human hand was moved while a voltage was applied to the rod so as to apply an electric field between the rod and the human hand. The result is shown in a figure.

(42) FIG. 11 shows a photograph at the time that the human hand was moved in a direction I while applying a voltage to the rod on which the charged particle detection film was formed. As shown in FIG. 11, it was found that the luminescent part moved along a moving direction of the human hand.

(43) Herein, since the potential of the human hand was lower than the potential (voltage) applied to the rod, it was found that the charged particles were emitted from the rod (charged particle-emitting part) toward the human hand (charged particle incident part).

Example 3

(44) Examples 1 and 2 were explained using the charged particle detection film containing the mechanoluminescent substance as the charged particle detection material, but the charged particle detection material according to the present invention is not limited thereto. In this example, a charged particle detection film (about 100 μm in thickness) containing SrAl.sub.2O.sub.4:Eu.sup.2+, Dy.sup.3+ as an afterglow substance instead of the mechanoluminescent substance SrAl.sub.2O.sub.4:Eu.sup.2+ was used. Then, an electric field (100 to 800 V/mm) was applied between the charged particle-emitting part 10 and the charged particle incident part 20 (gap distance: 10 mm) by activating the DC high-voltage generator in the same manner as in Example 1. The result is shown in a figure.

(45) As shown in FIG. 12, it was found when an electric field (100 to 800 V/mm) was applied between the charged particle-emitting part and the charged particle incident part, a substantially circular luminescent part with a center beneath the charged particle-emitting part was formed on the surface of the charged particle detection film of the charged particle incident part similarly to Example 1.

(46) As described above, it was found that emission of the charged particles or incidence of the charged particles could be easily detected in real time similarly to Examples 1 and 2 by using the charged particle detection material containing the afterglow substance and the charged particle detection film including the material. In addition, it was found that even charged particles which were generated by a discharge phenomenon caused in an extremely weak electric field (low potential difference, low energy) and had been unobservable by the prior art could be easily detected in real time by using the charged particle detection material according to the present embodiment.

Example 4

(47) In this example, a charged particle detection film (about 50 μm in thickness) containing Y.sub.2O.sub.2S:Tb.sup.3+ as a fluorescent substance instead of the mechanoluminescent substance SrAl.sub.2O.sub.4:Eu.sup.2+ in Example 1 was used. Then, a voltage (7 kV) was applied between the charged particle-emitting part and the charged particle incident part (gap distance: 10 mm) by activating the DC high-voltage generator in the same manner as in Example 1. The result is shown in FIG. 13.

(48) As shown in FIG. 13, it was found when a voltage (7 kV) was applied between the charged particle-emitting part and the charged particle incident part (gap distance: 10 mm), a substantially circular luminescent part with a center beneath the charged particle-emitting part was formed on the surface of the charged particle detection film of the charged particle incident part similarly to Example 1.

(49) As described above, it was found that emission of the charged particles or incidence of the charged particles could be easily detected in real time similarly to above-described Example 1 by using the charged particle detection material containing the fluorescent substance and the charged particle detection film including the material. In addition, it was found that even charged particles which were generated by a discharge phenomenon caused in an extremely weak electric field (low potential difference, low energy) and had been unobservable by the prior art could be easily detected in real time by using the charged particle detection material according to the present embodiment.

Example 5

(50) In this example, a charged particle detection film (about 50 μm in thickness) containing methyl salicylate as a fractoluminescent substance instead of the mechanoluminescent substance SrAl.sub.2O.sub.4:Eu.sup.2+ in Example 1 was used. Then, the result of a test under similar conditions to those in Example 1 is shown in FIG. 14.

(51) As shown in FIG. 14, it was found that a luminescent part was formed on the surface of the charged particle detection film of the charged particle incident part. From the above, it was found that the same effect as that of above-described Example could be obtained by using the charged particle detection material containing the fractoluminescent substance and the charged particle detection film including the material.

Example 6

(52) In this example, a fractoluminescent substance Eu(TTA).sub.3phen ([1,10-phenanthroline) tris [4,4,4-trifluoro-1-(2-thienyl)-1,3-butanedionato] europium(III)]) was used as a charged particle detection material instead of the mechanoluminescent substance SrAl.sub.2O.sub.4:Eu.sup.2+ in Example 1. Then, the result of a test under similar conditions to those in Example 1 is shown in FIG. 15.

(53) As shown in FIG. 15, it was found that a luminescent part was formed on the surface of the charged particle detection film of the charged particle incident part. From the above, it was found that the same effect as that of above-described Example could be obtained by using the charged particle detection material containing the fractoluminescent substance and the charged particle detection film including the material similarly to Example 5.

Example 7

(54) In this example, a charged particle detection films (about 50 μm in thickness; weight ratio of the afterglow substance: 70%) respectively containing SrAl.sub.2O.sub.4:Eu.sup.2+, Dy.sup.3+ and β-Zn.sub.3(PO4).sub.2:Mn.sup.2+, Ga.sup.3+ as the fluorescent substances instead of the mechanoluminescent substance SrAl.sub.2O.sub.4:Eu.sup.2+ in Example 1 was used. Then, a voltage (10 kV) was applied between the charged particle-emitting part and the charged particle incident part (gap distance: 10 mm). The result is shown in FIG. 16 (SrAl.sub.2O.sub.4:Eu.sup.2+, Dy.sup.3+) and FIG. 17 (β-Zn.sub.3(PO4).sub.2:Mn.sup.2+, Ga.sup.3+).

(55) As shown in FIGS. 16 and 17, it was found that a luminescent part was formed on the surface of the charged particle detection film of the charged particle incident part. From the above, it was found that the same effect as that of above-described Example could be obtained by using the charged particle detection film including the charged particle detection material containing the afterglow substance.

Embodiment 2

(56) Although Embodiment 1 was intended to detect the charged particles by forming the charged particle detection film including the charged particle detection material on the surface of the charged particle-emitting part 10 or the charged particle incident part 20, the present invention is not limited to this embodiment.

(57) For example, the charged particle detection material can be configured using a transparent/translucent material like glass or acrylic resin containing at least one of a fluorescent substance, a luminescent substance, an electroluminescent substance, a fractoluminescent substance, a photochromic substance, an afterglow substance, a photostimulated luminescent substance and a mechanoluminescent substance.

(58) When the charged particles are made to enter the charged particle detection material, the surface or the inside of the glass or the like emits light, and it is also possible to detect the depth of incidence of the charged particles inside of the glass or the like.

Embodiment 3

(59) Although the above-described embodiment was intended to detect the charged particle by forming the charged particle detection film including the charged particle detection material containing the mechanoluminescent substance and the like, the present invention is not limited to this embodiment. For example, a mechanoluminescent substance (powder) may be used as it is as the charged particle detection material.

(60) FIG. 18 shows a photograph at the time that charged particles were detected using a mechanoluminescent substance (powder) SrAl.sub.2O.sub.4:Eu.sup.2+ powder as a charged particle detection material. It was found that the charged particles could be detected in the same manner as the above-described embodiment even when using the charged particle detection material in such a form (powder).

(61) In addition, a luminescent sheet prepared using the charged particle detection material may be used instead of the mechanoluminescent substance (powder), in which a fine particle made of the mechanoluminescent substance and the like is dispersed.

(62) FIG. 19 shows a photograph at the time that charged particles were detected using a luminescent sheet prepared by curing a charged particle detection material in which a mechanoluminescent substance SrAl.sub.2O.sub.4:Eu.sup.2+ was dispersed in a photocurable acrylic resin (made by MICROJET Corporation). It was found that the charged particles could be detected in the same manner as the above-described embodiment even when using the charged particle detection material in such a form.

Embodiment 4

(63) In the above-described embodiment, the charged particle detection film including the charged particle detection material was formed on the charged particle-emitting part or the charged particle incident part having a certain thickness, but the present invention is not limited to this embodiment. For example, the same charged particle detection film as used in Example 1 may be formed on an aluminum foil. FIG. 20 shows a photograph at the time that a charged particle detection film composed of a photocurable acrylic resin (made by MICROJET Corporation) in which a charged particle detection material (SrAl.sub.2O.sub.4:Eu.sup.2+ (made by Sakai Chemical Industry Co., Ltd.)) was dispersed was formed on an aluminum foil, to which charged particles were made to enter. As shown in FIG. 20, it was found that charged particles could be detected in the same manner as the above-described embodiment even when a charged particle detection film made of a charged particle detection material was formed on a thin film.

(64) In addition, the charged particle detection material may be dispersed in e.g. a nonwoven fabric or the like. FIG. 21 shows a photograph at the time that the charged particle detection material was dispersed in and made to adhere to a paper nonwoven fabric, to which the charged particles were made to enter. As shown in FIG. 21, it was found that charged particles could be detected in the same manner as the above-described embodiment even when using a nonwoven fabric or the like in which the charged particle detection material was dispersed.

Embodiment 5

(65) Although the above-described embodiment was intended to detect the charged particles using the charged particle detection film or the charged particle detection material, the present invention is not limited to this embodiment. For example, the charged particles may be detected by using a charged particle detection liquid prepared by dispersing a charged particle detection material in a liquid.

(66) Charged particles entering a measurement object having a complicated shape can be easily visualized by using the charged particle detection liquid. In addition, the charged particle detection material is three-dimensionally dispersed in the charged particle detection liquid so that the trajectory of the charged particles moving in the liquid can be visualized.

Example 8

(67) A charged particle detection liquid was prepared, in which a mechanoluminescent substance SrAl.sub.2O.sub.4:Eu.sup.2+ (made by Sakai Chemical Industry Co., Ltd.) was dispersed in a transparent photocurable acrylic resin (VisiJet CR-CL, made by 3D Systems Corporation) (weight ratio of SrAl.sub.2O.sub.4:Eu.sup.2+: 70%). Then this charged particle detection liquid was dropped onto the stainless steel plate to form a puddle, to which the charged particles were made to enter from above in the same manner as in Example 1. The result is shown in FIG. 22. At this time, a rod-shaped member was brought into contact with the surface of the charged particle detection liquid for confirming that the photocurable acrylic resin was not cured, and the charged particles were made to enter the liquid thereafter.

(68) As a result, as shown in FIG. 22, it was found that the inside of the charged particle detection liquid emitted light. From this, it was found that the charged particle detection liquid could detect charged particles similarly to the charged particle detection film.

(69) Next, this liquid mixture was irradiated with ultraviolet ray at 365 nm (0.7 mW/cm.sup.2) for 10 minutes to cure only the surface of the charged particle detection liquid and then the charged particles were made to enter the surface similarly to the above. The result is shown in FIG. 23. As shown in FIG. 23, it was found that the cured portion (surface) emitted stronger light compared to before curing.

Other Embodiments

(70) If the charged particle detection material can be three-dimensionally dispersed in a gas such as air similarly to the above-described charged particle detection liquid, the trajectory of the charged particles moving in the gas can be detected.

(71) It should be noted that this application claims priority based on Japanese Patent Application No. 2016-149215 filed on Jul. 29, 2016, and the content of this application is incorporated herein as a reference.

REFERENCE NUMERALS

(72) 1 charged particle detection system 10 charged particle-emitting part 20 charged particle incident part 21 charged particle detection film 30 charged member P, P2, P3 luminescent part