KR100202859B1 - Fluorescent for manufacturing of electro-photographic screen of c.r.t - Google Patents

Abstract

A method of uniformly charging a photoconductive film to form a fluorescent film uniformly, an apparatus thereof, and a double discharge electrode structure are provided. The method includes: charging the photoconductive film once over the entire panel area by discharge while moving the discharge electrode from the initial position of one end of the panel to the other end; Shifting the discharge electrode at the other end of the panel by a predetermined distance in the longitudinal direction of the discharge electrode; Charging the photoconductive film twice over the entire panel area by discharge while moving the discharge electrode from the shifting position of the other end of the panel to the shifting position of one end of the panel; And shifting to an initial position of one end of the panel. In addition, the apparatus of the present invention, the electrode support block for holding the discharge electrode fixed; A charge transfer means for moving the electrode support block while guiding the electrode support block to move the discharge electrode between one end and the other end of the panel; A shift block supporting the charge transfer means; And shifting means for moving the shift block between predetermined positions together with the discharge electrode, the electrode support block, and the charge transfer means. In addition, the present invention provides a dual electrode structure in which the discharge electrodes are provided to be electrically insulated from each other and in parallel to each other, and each of the plurality of tips or a pair of discharge electrodes in which pins are staggered from each other. Accordingly, there is an effect that the photoconductive film can be uniformly charged in order to obtain a developing density such as a uniform phosphor.

Description

Photoelectric film charging method and apparatus for manufacturing electrophotographic screen of cathode ray tube and double discharge electrode structure

1 is a schematic front view in partial cross section of a color cathode ray tube;

FIG. 2 (a) is a partially enlarged sectional view showing the screen configuration of the cathode ray tube of FIG.

3 (a) to (e) are schematic diagrams schematically showing a dry electrophotographic screen manufacturing process for manufacturing a screen of a cathode ray tube using a discharge device.

4 (a) and (b) show a conventional photoconductive film discharge device for screen manufacturing of cathode ray tubes, (a) is a schematic cross-sectional view illustrating a relationship with a panel, and (b) shows a structure of a discharge electrode. Detailed cross section of the discharge electrode shown.

Figure 5 (a) is a schematic diagram for explaining the charging process by the discharge.

Figure 5 (b) is a schematic diagram showing a corona discharge phenomenon in the form of a crown.

5 (c) is a schematic diagram showing a streamer discharge phenomenon.

6 is a schematic plan view of a panel face plate for explaining the charging method according to the present invention.

7 (a) and (b) are schematic cross-sectional views of a charging device for carrying out a charging method according to the present invention.

8 (a) (b) and 9 (a) (b) show a double discharge electrode structure.

8 (a) and 8 (b) are cross-sectional views of the thin double discharge electrode structure and a front view of the double discharge electrode.

9A and 9B are cross-sectional views and front views of the fin structure double discharge electrode structure.

* Explanation of symbols for main parts of the drawings

10 cathode ray tube (CRT) 11 electron gun

12: panel 13: funnel

14 neck 15 anode button

16: shadow mask 17: deflection yoke

18: panel face plate 19a, 19b: electron beam

20: fluorescent screen (screen) 21: light absorbing material

22: aluminum thin film layer 32: conductive film

34: photoelectric film 36, 50: discharge device

38: light source (visible light) 40: lens

42: developing container 51: discharge electrode

51a: tip 52: support metal piece

53: insulation plate 54: insulator

61: electrode support block 62: transfer guide means

63: Daejeon transfer screw 64: Morphep motor

65: shift block 66: shift guide means

67: shifting air cylinder 70: frame

A: anode C: cathode

The present invention relates to a photoconductive film charging method for fabricating an electrophotographic screen of a cathode ray tube, a device thereof, and a double discharge electrode structure, and more particularly, to a method for uniformly charging a photoconductive film to uniformly form a fluorescent film, and A device and a double discharge electrode structure.

In general, the cathode ray tube, as shown in FIG. 1, has a vacuum bulb divided into a panel 12, a funnel 13 and a neck 14, and the neck 14 thereof. An electron gun 11 mounted therein and a shadow mask 16 mounted on the side wall of the panel 12 are provided.

A fluorescent surface 20 is formed on the inner surface of the face plate 18 of the panel 12, and the electron beams 19a and 19b emitted from the electron gun 11 are focused and accelerated by various lens systems, and the anode button 15 It is greatly accelerated by the high voltage applied through the deflection yoke (17) and deflected by the deflection yoke (17) and passed through the apertures or slits (16a) of the shadow mask (16) to the fluorescent surface (20).

The fluorescent surface 20 is formed on the back surface of the face plate 18. In the case of the color, as shown in FIG. 2, a plurality of stripe or dot-shaped phosphors R, G, and B in a constant array structure are shown. ) And a light absorbing material such as a black coating between the respective phosphors. In addition, the rear surface is formed with an aluminum thin film layer 22 as a conductive film layer, which serves to increase the luminance of the fluorescent surface, prevent ion damage of the fluorescent surface, and prevent potential drop of the fluorescent surface. Although not shown, a resin such as a lacquer is applied between the fluorescent surface 20 and the conductive film layer 22 in order to increase the plan view and reflectance of the aluminum thin film layer 22.

The conventional photolithographic wet process in which the fluorescent surface 20 is formed by applying and drying a suspension containing fluorescent particles such as a chromophoric phosphorus component or a suspension containing a light absorbing material is high quality. Not only does it not meet the requirements, but the manufacturing process and manufacturing equipment is complicated, the manufacturing cost is large, and also has a number of problems, such as the consumption of large amounts of clean water, wastewater generation, phosphorus emissions, hexavalent chromium photoresist emissions. Recently, an electrophotographic screen manufacturing method has been developed that improves the wet photolithography. In this electrophotographic manufacturing method, the wet still has the above-mentioned problems. It was considerably resolved.

A typical dry electrophotographic screen manufacturing method is disclosed in US Patent No. 4,921,767 (patented May 1, 1990), which is briefly described as follows.

3 (a) to (e) schematically show each basic process of the dry electrophotographic screen manufacturing method.

Before the panel 12 enters the screening process, the inner surface of the panel 12 is cleaned in various ways. Then, the inner surface of the panel 18 of the panel is coated with the electrically conductive film 32, as shown in FIG. 3A, and the photoconductive film 34 is coated thereon. As the compound used in the conductive film 32, inorganic conductive materials such as tin, indium oxide, or mixtures thereof are disclosed. As a raw material of the volatile conductive film, Albrich Chemical Co. 1,5-dimethyl-1,5-diaza-undicamethylene polymethobromide, hexadimethrin bromide) is disclosed. This polybrine is applied in an aqueous solution containing about 10% by weight of propanol and 10% by weight of water-soluble adhesive polymers (polyvinyl alcohol, polyacrylic acid, polyamide, etc.) and dried to give 10 ⁸ Ω / (ohms per square unit) to form a conductive film 32 having a surface resistance of less than about 1-2㎛. The photoconductive film 34 coated on the conductive film 32 includes n-ethyl carbazole or n dissolved in a volatile organic polymer (polyvinylcarbazole) or a polymer provider (polymethylmethacrylate or polypropylene carbonate). A coating liquid comprising an organic monomer such as -vinylcarbazole or tetraphenylbutatriene, a suitable photoconductive dye and a solvent is disclosed. Its photoconductive dye reacts to visible light (preferably 400-700nm wavelength), such as crystal violet, chloridine blue, and rhodamine EG. About 0.1 to 0.4% by weight. As the solvent, organic substances such as chlorobenzene and cyclopentanone that do not contaminate the conductive film 32 are disclosed. The photosensitive film 34 having such a composition has a thickness of 2-6 mu.

FIG. 3B schematically shows a charging process in which the photoconductive film 34 of the double coated face plate 18 is charged with positive charge in the dark room by the conventional discharge device 36 as described above. The discharge device 36 is applied to the + electrode of the DC power supply of +200 to +700 volts, the-electrode is applied to the conductive film 32 and ground at the same time, the discharge device 36 applied to the + electrode in this way By moving across the photoconductor film 34 of the face plate 18, the photoconductor film 34 is charged with positive charge.

3 (c) illustrates an exposure process, wherein the photoconductive film 34 charged as described above is applied to the xenon flash lamp 38 having the lens 40 through the shadow mask 16 in the dark room as well. Is exposed. Therefore, the shadow mask 16 is first mounted on the panel 12 and the conductive film 32 is earthed. In this process, the light beam of the lamp 38 is irradiated to the photoconductive film 34 through the lens 40 and the shadow mask 16 by turning on the xenon flash lamp 38, so that the aperture of the shadow mask 16 Portions of the photoconductive film 34 corresponding to the slit 16a are exposed, and positive charges of the exposed portions are emitted through the conductive film 32 by the visible light, as shown in FIG. Only the exposed portion is in a non-charged state. In the case of the xenon flash lamp 38 described above, in order to attach a light absorbing material to the color, the xenon flash lamp 38 has a structure in which the light beam moves between three positions so as to coincide with the incident angle of each electron beam.

FIG. 3 (d) schematically illustrates the development (fluorescence infiltration or attachment of light absorbing material) process. In this step, the developing container 42 contains a dry light absorbing material fine powder or dry phosphor fine powder and a carrier bead capable of generating static electricity by contact with each powder. The carrier beads for the light absorbing material are in contact with the fine powder, so that the light absorbing material particles can be charged with -charge and the fluorescent particles with + charge. The panel 12 from which the shadow mask 16 is removed is installed on the developing container 42 containing the above-described powder so that the photoconductive film 34 can contact the powder.

At this time, the negatively charged light absorbing material in the mixed powder is attached to the non-exposed portion of the photoconductive film 34 charged with positive charge, and the positively charged fluorescent particles are positively charged photoelectric charge. In the non-exposed part of the coating film 34, it adheres only to the exposed part of the photoconductive film 34 which is in a non-charged state by reversal developing.

FIG. 3 (E) shows a fixing process by infrared heating, in which dry light absorbing material particles or dry fluorescent particles attached in the above-described developing process are added to each other, and the photoconductive film 34 Is stuck on. Thus, a suitable polymer component that is fused by heating is included in the photoconductive film 34 and dry light absorbing material particles or respective fluorescent sites in the line.

FIG. 4 (a) specifically illustrates the relationship between the conventional discharge device 36 and the panel 12 used in the charging process of FIG. 3 (b), and FIG. 4 (b) shows the conventional discharge. The structure of the device 36 is shown in cross section.

In order to be uniformly exposed and developed in the exposure process of FIG. 3 (c) and the developing process of FIG. 3 (d) described above, the charge amount to the tube conductive film 34 is preferably uniform over the entire area.

However, the charge amount depends on the discharge capacity of the discharge device 36, and it is not easy to discharge evenly from the inherent shape for discharge of the discharge device 36.

That is, in FIG. 4 (b), the discharge device 36 includes a discharge electrode 51 in the center of tungsten or stainless steel plate, an insulating plate 53 surrounding the periphery thereof, and a pair of supports for supporting them. And an insulator 54 which is charged between the metal piece 52 and the supporting metal piece 52 and the discharge electrode to insulate the discharge electrode 51.

The upper end of the discharge electrode 51 is formed as a plurality of tip-shaped teeth 51a having a sharp tooth shape to cause a discharge toward the counter electrode as a free end for discharging.

An adjustable direct current voltage V is applied to the discharge electrode 51 to approximately +1 KV to charge the photoconductive film 34 with positive charge.

As such, the discharge capacity between the discharge electrode 51 and the counter electrode 32 that charges the photoconductor film 34 with positive charge is the distance d ₁ between the tip 51a and the counter electrode 32 and the distance between the tips. (d ₂ ), the shape of the tip and its sharpness are greatly influenced, and the amount of charge charged to the photoconductive film 34 is required even for the tip shape in order to cause discharge, so that the entire surface even in the center of the panel It cannot be uniform across. That is, the maximum discharge occurs at the uppermost portion closest to the tip 51a, and weakens toward the circumference.

Accordingly, there is a problem of causing uneven exposure and development in the above-described exposure process and development process and causing the phosphor particles to be uneven even in a desired arrangement structure.

In addition, in FIG. 4 (a), the panel 12 may be divided into a curved inner panel 18 and a panel side wall portion 18a, which has a periphery b, rather than a central portion a of the panel surface 18. In c), corona discharge is strongly generated, which makes it difficult to secure uniformity of charging.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and a photoconductor charging method and apparatus for manufacturing an electrophotographic screen of a cathode ray tube capable of uniformly charging a photoconductor film in order to obtain a developing density of a uniform phosphor and the like, and a double The purpose is to provide a discharge electrode structure.

In order to achieve the object of the present invention, the present invention, the photoelectric film charging method for screen production of a cathode ray tube for charging the photoelectric film on the opposite electrode side by causing a discharge between the opposite electrode and the discharge electrode of the conductive film on the inner surface of the panel The method of claim 1, further comprising: charging the photoconductive film once over the entire panel area by discharge while moving the discharge electrode from the initial position of one end of the panel to the other end; Shifting the discharge electrode at the other end of the panel by a predetermined distance in the longitudinal direction of the discharge electrode; Charging the photoconductive film twice over the entire panel area by discharge while moving the discharge electrode from the shifting position of the other end of the panel to the shifting position of one end of the panel; And shifting the discharge electrode to a longitudinal direction of the discharge electrode and to an initial position of one end of the panel at a shifting position of one end of the panel. It provides a photoelectric film charging method for.

In addition, the present invention provides a discharge electrode for charging the photoconductive film formed on the conductive film by causing a discharge by using the conductive film formed on the inner surface of the panel face plate as a counter electrode to manufacture the screen of the panel surface plate of the cathode ray tube. Claims [1] A photoconductive film discharge device for screen manufacturing of a cathode ray tube, comprising: an electrode support block fixedly supporting a discharge electrode; Charge transfer means for moving the electrode support block while guiding the discharge electrode to move the discharge electrode between one end and the other end of the panel; A shift block supporting the charge transfer means; And shifting means for moving the shift block between predetermined positions together with the discharge electrode, the electrode support block, and the charge transfer means. To provide.

In addition, the present invention provides a discharge electrode for charging the photoconductive film formed on the conductive film by causing a discharge by using the conductive film formed on the inner surface of the panel face plate as a counter electrode to manufacture the screen of the panel surface plate of the cathode ray tube. In the photoconductive film discharge device for screen production of a cathode ray tube, the discharge electrodes are provided to be electrically insulated from each other and parallel to each other, and each of the plurality of tips or a pair of discharge electrodes having pins alternate with each other. Provided is a dual discharge electrode structure for producing an electrophotographic screen of a cathode ray tube.

Hereinafter, with reference to the accompanying drawings will be described embodiments of the present invention.

First, when the discharge process is described, when high pressure is applied to the anode A in FIG. 5 (a), electrons and cations existing in the atmosphere between the anode A and the cathode C are moved to the opposite electrode portions, respectively. . The ionization phenomenon is promoted due to the cations generated during the movement, the collision between the electrons, etc. The cations generated by the ionization are moved to and attached to the cathode C, and the inner surface of the panel is charged. FIG. 5 (b) (c) shows the form of the discharge, which is shown in FIG. Likewise, the corona discharge phenomenon discharged in the crown form and the streamer discharge phenomenon as shown in FIG. Even in the crown form, the positive charge density is higher in the central part than in the peripheral part.

As described above, the discharge phenomenon occurs differently according to various conditions, and since the inner surface of the panel face plate 18 is a curved surface, in order to secure the uniformity of such discharge, the crowns as shown in FIG. Corona discharge in the form occurs and the peripheral portion of the crown form is superimposed so that the discharge is uniformly distributed over the entire surface to some extent. In addition, if a streamer discharge phenomenon occurs as shown in FIG. 5C by increasing the voltage, the photoconductive film 34 is damaged, which is not preferable.

In consideration of the above-described discharge phenomenon, the discharge state of the conventional discharge device 36 shown in FIG. 4 (a) (b) for the cause of the strong discharge at the periphery rather than the center of the panel face plate 18 is described. The test and analysis resulted in the following conclusions.

That is, even when the same voltage was applied to the discharge electrode 51 and the intervals d ₁ and d ₂ were the same, the electric field distribution appeared relatively strong and nonuniform at the periphery thereof. This means that ionization occurs more strongly at the periphery than at the center, and this strong ionization causes the discharge to be concentrated at the periphery. This phenomenon can be interpreted for two reasons. The first is that since the peripheral portion is bent at almost right angles in the overall shape side of the discharge electrode 51, the discharge can be concentrated on the bent portion as a whole. Second, in the ionization for discharge, air can be assumed as a kind of resistor, and the surrounding air can make more discharge path than air existing near the center of the electrode. You lose. In particular, since the discharge electrode 51 moves along the curvature of the inner surface of the panel face plate 18, the flow of air between the upper portion of the tip 51a and the adjacent tip 51a also occurs in the peripheral portion rather than the center portion. As a result, ionization by air at the periphery can occur more strongly and discharge is concentrated.

6 is a schematic view of a photoelectric film charging method according to an embodiment of the present invention. That is, the discharge electrode 51 moves once in one direction (left end) of the face plate 18 of the panel 12 in the direction of arrow F to generate a one-time discharge between the conductive films 32 and the inner surface of the face plate 18. The applied photoconductive film 34 is charged with a predetermined polarity. After the discharge electrode 51 moves while discharging to the other end (right end) of the panel face plate 18, it shifts in the direction of the arrow sb and then moves from the position 51 'to the direction of the arrow B again. While causing two discharges.

Since the shifting distance is 2/1 of the pitch of the tip 51a of the discharge electrode 51, the shifting is performed in such a manner that the discharge occurs with the conductive film 32 of the panel face plate 18 twice. As described above, the crown-shaped corona discharge from the tip 51a of the discharge electrode 51 can eliminate the nonuniformity of the discharge in the crown shape due to the corona discharge.

An apparatus for carrying out such a charging method is shown in Figs. 7A and 7B, and Fig. 7A is a cross-sectional view taken along the length of the discharge electrode 51, and Fig. 7B. Is a cross-sectional view taken along the line AA of FIG.

The discharge electrode 51 is fixed to the electrode support block 61, and the electrode support block 61 is guided by the movement guide means 66 while the step motor 64, which is the charge transfer means, and the charge transfer screw. By 63, the discharge electrode 51 is reciprocated in the direction of arrow Y between both ends of the panel 12. As shown in FIG. Referring to FIG. 7 (b), a high voltage is applied to the discharge electrode 51 while the discharge electrode 51 is moved, thereby causing a discharge. Accordingly, charging is performed on the photoconductive film 34 of the panel face plate 18.

The step motor 64, the charge transfer screw 63, the movement guide means 62, and the electrode support block 61 are fixed to the shift block 65, and the shifting air cylinder 67, which is a shifting means, The shift guide means 65 reciprocates with the shift block 65 by a predetermined length in the electrode length direction, that is, in the arrow X direction of FIG.

The air cylinder 67 and the shift guide means 65 are fixed to the frame 70 on which the panel 12 is loaded.

According to the above-described configuration, the discharge electrode 51 moves by 1/2 pitch of the discharge team 51a to perform discharge twice, thereby completely eliminating the nonuniformity of the crown-shaped corona discharge. The coating film 34 is uniformly charged, and in the developing process, the developing density can be made uniform, thereby improving the image quality of the cathode ray tube.

8 (a) and 8 (b) show a thin double discharge electrode structure according to an embodiment of the present invention. The double discharge electrode is composed of a pair of thin plate discharge electrodes 51 and 52 in which the discharge tips 51a and 55a are staggered by half pitch from each other. In this configuration, crown-shaped discharges are generated in the discharge teams 51a and 55a of the pair of discharge electrodes 51 and 55, respectively, in a staggered pitch of 1/2 pitch. The effect of can be obtained.

In addition, in the case of the above-mentioned two shifting discharges, when the discharge tips 51a differ in pitch from each other in the center part and the peripheral part, the nonuniformity of the corona discharge cannot still be completely removed, but in the case of FIG. 8 (a) (b) Even if the pitch of the discharge tip 51a of one discharge electrode 51 is different, the pair of discharge tips 55a of the other discharge electrode 55 respectively adjacent to the discharge electrode 51 ( By forming it in the center of 51a), it is possible to completely eliminate the nonuniformity of the corona discharge remaining during two shifting discharges in the case of different pitches as described above.

FIG. 9A illustrates a fin structure dual discharge electrode structure according to another embodiment of the present invention in detail, and FIG. 9B is a cross-sectional view taken along the line C-C of FIG. The pin structure double discharge electrode includes two pairs of electrode pins (P1, P2 .... Pi ..... Pn) (Q1, Q2, ...) in which the electrode pins (Pi, Qi) are alternately arranged. Qi, ... Qn).

The tips of the electrode pins Pi and Qi form a predetermined curvature to cause discharge of the conductive film 32 of the panel face plate 18, which is the counter electrode. The electrode pins Pi and Qi are electrically connected to a common auxiliary electrode piece Pa via a pair of resistors Ri and Si, so that the same high voltage is applied to the auxiliary electrode piece Pa. Even when applied, the discharge can be controlled by the change in the resistance value. In addition, even if such a resistance value is not changed, a large resistance value of about 10 ⁵ Ω decreases the rate of change of the total resistance between the electrode pins, thereby causing a relatively uniform discharge.

According to the fin-type double discharge electrodes Pi and Qi which take all the advantages of the double-discharge structure together with the advantages of the fin-type discharge electrode, a substantially uniform discharge is performed over the entire inner surface of the panel face plate 18, thereby providing a photoconductive film ( 34 can be charged almost uniformly.

Although embodiments of the present invention have been described above, the present invention is not limited thereto, and various changes and modifications will be possible to those skilled in the art from the matters described in the claims.

Claims (9)

A photoconductor film charging method for screen production of a cathode ray tube for charging a photoconductor film on a counter electrode side by causing a discharge between a counter electrode and a discharge electrode on the inner surface of the panel, wherein the discharge electrode is positioned at an initial position of one end of the panel. Charging the photoconductive film once over the entire panel area by discharging while ising to the other end at; Shifting the discharge electrode at the other end of the panel by a predetermined distance in the longitudinal direction of the discharge electrode; Charging the photoconductive film twice over the entire panel area by discharge while moving the discharge electrode from the shifting position of the other end to the shifting position of one end of the panel; And shifting the discharge electrode to a longitudinal direction of the discharge electrode and to an initial position of one end of the panel at a shifting position of one end of the panel. Photoelectric film charging method for The photoelectric for manufacturing an electrophotographic screen of a cathode ray tube according to claim 1, wherein when the pitch between the plurality of tips is constant, the predetermined distance in the shifting step is 1/2 of the pitch between the tips. Coating film charging method. The method of claim 1, wherein the shifting steps shift the panel instead of shifting the discharge electrode. For manufacturing a screen of a panel of a cathode ray tube, a screen is produced for a cathode ray tube having a discharge electrode for charging a photoconductive film formed on the conductive film by causing a discharge using a conductive film formed on the inner surface of the panel surface as a counter electrode. A photoconductive film discharge device comprising: an electrode support block for fixedly supporting a discharge electrode; Charge transfer means for moving the electrode support block while guiding the discharge electrode to move the discharge electrode between one end and the other end of the panel; A shift block supporting the charge transfer means; And shifting means for moving the shift block between predetermined positions together with the discharge electrode, the electrode support block, and the charge transfer means. . The method of claim 4; The charge transfer means includes a step motor, a charge transfer screw and a transfer guide means connected to the shaft of the step motor; The shifting means is a photoelectric film charging apparatus for manufacturing an electrophotographic screen of a cathode ray tube, characterized in that it comprises a shifting air cylinder and a shifting guide means. The method of claim 4 or 5; And the shift block supports a panel instead of the charge transfer means, and the shifting means moves the shift block together with the panel. To produce a screen of the panel face plate of the cathode ray tube, a tooth-shaped thin plate having a plurality of tips for charging the photoconductor film formed on the conductive film by causing discharge by using a conductive film formed on the inner surface of the panel face plate as a counter electrode. In a photoconductor film discharge device for screen production of a cathode ray tube having discharge electrodes, the discharge electrodes are electrically insulated from each other and are arranged adjacent to each other in parallel, and a pair of thin plate discharge electrodes in which a plurality of tips thereof are alternately formed. Dual discharge electrode structure for manufacturing an electrophotographic screen of a cathode ray tube, characterized in that configured. For manufacturing a screen of a panel of a cathode ray tube, a screen is produced for a cathode ray tube having a discharge electrode for charging a photoconductive film formed on the conductive film by causing a discharge using a conductive film formed on the inner surface of the panel surface as a counter electrode. In the photoconductive film discharging device, the discharge electrodes are arranged in a straight line, the ends of which form a constant curvature, and each pair is composed of a pair of a plurality of pins arranged in parallel and staggered adjacent to each other of the cathode ray tube Dual discharge electrode structure for electrophotographic screen production. The dual discharge electrode structure for manufacturing an electrophotographic screen of a cathode ray tube according to claim 8, wherein the pair of electrode pins are electrically connected to an electrode auxiliary piece to which the same potential is applied through a resistor.