JP2002313230A - Forming method for fluorescent surface - Google Patents

Abstract

PROBLEM TO BE SOLVED: To easily form a fluorescent surface, having a plurality of fluorescent parts, especially to easily form respective fluorescent parts, together with the fluorescent surface using evaporation method. SOLUTION: Conductive films 15, 25 are formed at the part, corresponding to the formation region, to which respective fluorescent layers 13, 23 are to be formed. Leader line parts 16, 26, impressing voltages to respective conduction films 15, 16, are formed. Afterwards, by selectively impressing voltages to respective leader line parts 16, 26 in an electrodeposition solution, the fluorescent layers 13, 23, covering the conduction films, are selectively formed on the conductive films 15, 25 respectively. As a result of this, respective fluorescent parts 51, 52 can be formed by the identical manufacturing method (electrodeposition method) which makes the formation of the fluorescent surface easy, comparing with the method forming the fluorescent parts 51, 52 by the manufacturing methods which are different from each other.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for forming a phosphor screen having a plurality of phosphor parts, and more particularly, to a method for forming a phosphor screen using an evaporation method.

[0002]

2. Description of the Related Art Conventionally, a cathode ray tube (CRT; Cathode Ray Tube) has been used in television receivers and various monitor devices.
Tube) is widely used. The cathode ray tube emits an electron beam from an electron gun provided inside the tube (inside the cathode ray tube) toward a fluorescent screen, and forms a scan screen on the tube surface according to the scanning of the electron beam. Cathode ray tubes are roughly classified into straight type and flat type. The straight type cathode ray tube has a structure in which an electron gun is arranged so that an emission port of an electron beam faces a fluorescent screen, and the electron beam is irradiated almost perpendicularly to a center of the fluorescent screen. On the other hand, the flat type cathode ray tube has a structure in which an electron gun and a phosphor screen are provided on substantially the same plane, and an electron beam is obliquely applied to the phosphor screen. The flat-type cathode ray tube can be made thinner than a straight type cathode-ray tube, so that it is often used for a relatively small device, for example, a monitor unit of a base unit in a door phone device and a portable TV (television) monitor. ing.

[0003] Some cathode ray tubes perform color display on the entire screen, but there is also a demand for a device that simply displays images in monochrome (monochromatic), and development has been made. In particular, flat-type cathode ray tubes of a monochrome display type are often used for doorphone devices. The cathode ray tube of the monochrome display system forms the entire phosphor screen with, for example, a white light-emitting phosphor, and scans the phosphor screen with one electron beam.
Displays monochrome images.

[0004]

By the way, there is a demand for an apparatus using a cathode ray tube of a monochrome display system to display an image partially in color. For example, a door phone device is combined with various sensor devices such as a fire detector and a gas leak detector, and can function as a security system as a whole. In the case of such a system configuration, in order to call a user's attention, the occurrence of an abnormal situation is expressed in a different color (for example, red) from a normal monochrome display on the master unit, and a warning display is performed. Is desirable.

Accordingly, the applicant of the present application has filed Japanese Patent Application No. 2000-045114.
Also, in Japanese Patent Application No. 2000-117594 and the like, a technique has been proposed that enables a color display to be partially performed even with a cathode ray tube of a monochrome display system.

Hereinafter, the prior invention by the present applicant will be briefly described with reference to FIGS. 8 (A) and 8 (B). FIG.
2A and 2B show a simplified image display portion of a flat cathode ray tube. As shown in FIG. 8A, in a conventional monochrome display type flat cathode ray tube 110, the entire image display area 111 is formed of a single-color phosphor layer (for example, a white light-emitting phosphor layer) 112. .

On the other hand, the flat cathode ray tube 120 according to the invention of the present applicant is provided with a monochromatic phosphor layer 122 as shown in FIG. 8 (B), so that a first monochrome image is displayed. In addition to the phosphor section 121, a second color display
Phosphor section 123 is provided. Second phosphor section 123
Is provided with another phosphor layer 124 that emits light in a different color from the phosphor layer 122 provided in the first phosphor section 121. The phosphor layer 124 is previously formed into a pattern in a shape imitating an image to be displayed. The phosphor layer 124 of the second phosphor section 123 is formed in a single color (for example, red) or a plurality of colors according to an image to be displayed. Thus, when the second phosphor portion 123 is scanned with the electron beam, the phosphor pattern portion emits light, and an icon-like color image is displayed. At this time, by forming a plurality of phosphor patterns (icon patterns) 124A, 124B, and 124C on the second phosphor section 123, a plurality of icon images can be displayed simultaneously or individually.

As described above, the cathode ray tube according to the invention of the applicant of the present invention displays an icon-like image in color in addition to a monochrome image in normal display. Hereinafter, the cathode ray tube having the icon display function is simply referred to as “icon CR”.
T ".

By the way, in the conventional flat cathode ray tube 110 shown in FIG. 8A, a transfer method, an electrodeposition method, a slurry method, and the like are conventionally known as a method of forming the phosphor screen. . At this time, since the conventional flat cathode ray tube 110 has only a single phosphor portion, any one of the methods may be used to form the phosphor screen.

On the other hand, the icon CRT shown in FIG.
Since 120 has a plurality of phosphor parts, each phosphor part can be formed by a different method. However, when each phosphor part is formed by a different method, there is a problem that a manufacturing process is complicated. Therefore, it is desired to develop a technology that enables the formation of each phosphor portion to be performed in the same manner as possible and in a simplified manner.

The present invention has been made in view of the above problems, and an object of the present invention is to make it possible to easily form a phosphor screen having a plurality of phosphor sections.
It is an object of the present invention to provide a method for forming a phosphor screen which can be easily formed by using an evaporation method.

[0012]

According to a method of forming a phosphor screen according to the present invention, a first conductive film is formed over the entire region where a first phosphor section is formed, and a voltage is applied to the first conductive film. Forming a first lead-out portion for forming the second phosphor layer, and forming a second conductive film having the same shape as the phosphor pattern at the formation position of the second phosphor layer in the formation region of the second phosphor portion. Forming, and forming a second lead line portion for applying a voltage to the second conductive film, and selectively applying a voltage to each lead line portion in the electrodeposition liquid, First
Selectively forming a first phosphor layer and a second phosphor layer on the conductive film and the second conductive film, respectively.

In the method for forming a phosphor screen according to the present invention,
It is desirable that the conductive films and the lead lines are formed simultaneously by, for example, covering a region other than the formation regions of the conductive films and the lead lines with a mask, and by vapor deposition.

In the present invention, the first phosphor layer is made of, for example, a white light-emitting phosphor that emits white light. The white light-emitting phosphor is a phosphor that emits white light alone, for example, a phosphor in which a blue light-emitting phosphor and a yellow light-emitting phosphor are mixed at an appropriate ratio, so as to apparently emit white light. Including those that are not.

In the method of forming a phosphor screen according to the present invention, first, a conductive film is formed in a portion corresponding to a region where each phosphor layer is formed. A lead line portion for applying a voltage is formed in each of the conductive films. Next, in the electrodeposition liquid,
A voltage is selectively applied to each lead line portion, and a first phosphor layer and a second phosphor layer are selectively formed on the first conductive film and the second conductive film, respectively. Is done. As described above, in the method of forming a phosphor screen according to the present invention, since each phosphor part is formed by using the same electrodeposition method, it is easier to form each phosphor part by a different method. A phosphor screen is formed.

[0016]

Embodiments of the present invention will be described below in detail with reference to the drawings.

[First Embodiment] First, referring to FIGS. 1 and 2, a flat cathode ray tube manufactured by using the method for forming a phosphor screen according to the first embodiment of the present invention will be described. The configuration will be described. In the drawing, a reflection type is shown as an example of a flat type cathode ray tube. FIG. 1 corresponds to a cross section taken along a line II in FIG.

As shown in FIG. 1, a flat cathode ray tube 30
Has a screen panel 31, a front panel 32, and a funnel section 33. Screen panel 3
The front panel 32 and the funnel section 33 are made of, for example, a transparent glass member, and form a flat glass tube (flat tube) by a three-body structure of these panels.

At the rear end of the funnel 33, an electron gun 35 for emitting an electron beam EB is provided. An inner conductive film 53 made of, for example, a carbon film is applied to the inner wall surface of the funnel portion 33. The internal conductive film 53 is electrically connected to an anode terminal (not shown) provided in the funnel section 33 so that a high voltage (anode voltage) HV is applied. Although not shown, a deflection yoke for deflecting the electron beam EB emitted from the electron gun 35 is arranged on the outer peripheral portion of the funnel section 33.

The front panel 32 has a flat plate shape. On the other hand, the screen panel 31 has a shape curved in the vertical direction (up and down direction). A fluorescent screen 50 is formed on the inner wall surface side of the screen panel 31, that is, on the surface side facing the front panel 32. Phosphor screen 50
Has a first phosphor section 51 and a second phosphor section 52.

The first phosphor section 51 is for displaying a normal monochrome image, and is provided with a screen panel 31.
The first conductive film 15 and the first phosphor layer 13 are laminated in this order from the inner wall surface side. On the other hand, the second phosphor section 51 is for displaying an icon-shaped image, and is arranged in order from the inner wall surface side of the screen panel 31.
The second conductive film 25 and the second phosphor layer 23 are stacked.

First conductive film 15 and second conductive film 25
Is composed of, for example, an aluminum (Al) vapor-deposited film. The first conductive film 15 and the second conductive film 25
The first phosphor layer 13 and the second phosphor layer 23 respectively
And is formed on the inner wall surface of the screen panel 31 in substantially the same shape. First conductive film 15 and second conductive film 2
5, as shown in FIGS. 4 and 5, lead lines 16 and 26 (26 A, 26 B, 26 C) are provided extending toward the funnel 33. As shown in FIG. 5, the lead lines 16 and 26 are electrically connected to each other at a common connection portion 54A of a conductive film 54 made of, for example, a carbon film. Conductive conductive film 54
Are also electrically connected to the internal conductive film 53 of the funnel portion 33. Thus, the anode voltage HV is applied to the first conductive film 15 and the second conductive film 25 via the internal conductive film 53 and the conductive film 54 for conduction. Each of the conductive films 15 and 25 has a function as an electrode layer to which the anode voltage HV is applied as described above.
It also has a function as a reflection film. That is, each of the conductive films 15 and 25 emits the electron beam EB to each of the phosphor layers 13 and 2.
3, each of the emitted light rays R1, R
2 is reflected to the front panel 32 side.

Each of the first phosphor layer 13 and the second phosphor layer 23 emits light in response to the incidence of the electron beam EB, but is composed of different types of phosphors. More specifically, the first phosphor layer 13 is made of, for example, a white light-emitting phosphor. The first phosphor layer 13 has at least an area including a main image display area 32A (corresponding to a normal effective screen area) (FIG. 2) for displaying a normal image, as shown in FIG. It is provided uniformly throughout.

On the other hand, the second phosphor layer 23 is made of another phosphor that emits light of a different color from the first phosphor layer 13. The second phosphor layer 23 has an icon-shaped color image (icon image) 42 (42A, 42A) different from the main image 41 displayed in the main image display area 32A.
B, 42C) in the icon display area 32B (FIG. 2). This second phosphor layer 2
5, as shown in FIG. 5, a pattern is previously formed in a shape equivalent to the image to be displayed (a shape imitating the icon image 42). Therefore, the second phosphor layer 23 does not need to be provided in the entire area corresponding to the icon display area 32B, but is basically provided only in the area where the icon image 42 is to be displayed. It is. In this case, a portion where the icon image 42 is not displayed (a portion where the second phosphor layer 23 is not provided).
It is preferable to form, for example, a so-called black matrix structure in which black materials (eg, graphite) are laminated.

Each of the phosphor layers 23A of the second phosphor layer 23,
23B and 23C (FIG. 5) are formed in a single color (for example, red) or a plurality of colors according to the icon image 42 to be displayed. Thus, when scanning is performed with the electron beam EB, the scanned phosphor pattern portion emits light, and the icon image 42 corresponding to the phosphor pattern is displayed in the icon display area 32B by the emitted light beam R2. By forming a fluorescent pattern including a plurality of phosphor layers 23A, 23B, and 23C in a region corresponding to the icon display region 32B as shown in FIG. 5, a plurality of icon images 42A, 42B, and 42C can be simultaneously or individually. Can be displayed.

In FIG. 2, as shown in FIG. 5, the second phosphor layer 23 is formed of star-shaped, square-shaped and round-shaped phosphor layers 23A, 23B, and 23C to form a star-shaped phosphor layer.
Square and round icon images 42A, 42B, 42
The example which displays C is shown. However, the second
The shape of the phosphor layer 23 can be any shape such as symbols, characters, and various patterns.
Can be displayed in any shape.

The flat cathode ray tube 30 having the above configuration
Is applied to a door phone device with a security function, for example, the following display operation is performed. Note that the doorphone device is a general name of a device in which a slave unit and a master unit are connected by a communication cable. Peripheral devices such as a fire detector are connected to the parent device in a door phone device with a security function. The flat cathode ray tube 30 is applied to a monitor unit of a parent device in such an intercom apparatus.

First, in the main image display area 32A, an image picked up by a video camera of a slave unit is displayed in monochrome (black and white). In this case, the first phosphor layer 13 in the first phosphor section 51 is scanned by the electron beam EB. At this time, the emitted light R1 generated in the phosphor layer 13 is:
The light is reflected toward the front panel 32 by the function of the first conductive film 15 as a reflection film. This first conductive film 15
An optical image formed by the light beam R1 reflected by the light source is observed as a main image 41 from the front panel 32 side.

On the other hand, in the icon display area 32B, for example, icon images are displayed in conjunction with the security system. That is, for example, an icon image is displayed according to a detection signal from a peripheral device having a fire detection function. In this case, the second phosphor layer 23 in the second phosphor section 52 is scanned by the electron beam EB, and at this time, the icon image 42 to be displayed is scanned.
Is only the area where the phosphor pattern corresponding to is provided. That is, for example, it is only an area where a fire detecting phosphor pattern (for example, a flame-shaped phosphor pattern) is formed. At this time, the emitted light beam R2 generated by scanning with the electron beam EB is reflected toward the front panel 32 by the function of the second conductive film 25 as a reflection film. The color icon image 42 formed by the light beam R2 reflected by the second conductive film 25
Are observed from the front panel 32 side.

Next, a method of manufacturing the flat type cathode ray tube 30 and particularly a method of forming the fluorescent screen 50 will be described in detail with reference to the flowchart shown in FIG.

First, a first conductive film 15 and a second conductive film 25 made of, for example, an aluminum (Al) vapor-deposited film are formed on the inner surface of the screen panel 31 as shown in FIG. 4 (step S1). ). At this time, the first conductive film 15 is formed over the entire formation region of the first phosphor part 51. At the same time, a lead line portion 16 for applying a voltage to the first conductive film 15 is formed. On the other hand, the second conductive film 25 is formed in the region where the second phosphor portion 52 is formed.
At the position where the second phosphor layer 23 is formed, it is formed in the same shape as the phosphor pattern (icon pattern). At the same time, a lead line portion 26 (26A, 26B, 26C) for applying a voltage to the second conductive film 25 is formed.
The conductive films 15 and 25 and the lead lines 16 and 26
Are, for example, conductive films 15 and 25 and lead line portion 1
It is possible to cover regions other than the formation regions 6 and 26 with a mask and simultaneously form them collectively by an evaporation method.

Next, on the first conductive film 15 and the second conductive film 25, the first phosphor layer 13 and the second
The phosphor layer 23 is selectively formed by electrodeposition (step S2).

The electrodeposition of the phosphor layers 13 and 23 is performed, for example, using the electrodeposition apparatus shown in FIG. The electrodeposition apparatus holds an electrodeposition tank 61 containing an electrodeposition liquid 62 and a screen panel 31 to be electrodeposited, and applies a voltage to the conductive films 15 and 25 on which the phosphor layers 13 and 23 are formed. Electrode / holding portion 63 having a function of applying
It mainly includes an opposing electrode 64 disposed opposite to the surface on which the electrodes 3 and 23 are formed, and a power supply 65 for supplying a voltage to the electrode / holding portion 63 and the opposing electrode 64.

As the electrodeposition liquid 62, for example, a mixture prepared by mixing a mixture of a phosphor, indium oxide, aluminum nitrate, and lanthanum nitrate with pure water, isopropyl alcohol, and glycerin and ultrasonically dispersing the mixture is used. . At this time, as the phosphor dispersed in the electrodeposition liquid 62, a phosphor corresponding to the type (color) of the phosphor layer to be formed is used. For example, when forming the first phosphor layer 13, a white light-emitting phosphor, for example, Y ₂ O ₂ S (sulfide yttrium oxide) or Y ₂ O ₂ S: Tb (sulfide yttrium oxide: activated with terbium) Such fluorescent powder is dispersed in the electrodeposition liquid 62. Also, the second phosphor layer 23
Is formed, a fluorescent powder having a luminescent color corresponding to the type of the icon image 42 to be displayed is applied to the electrodeposition liquid 62.
Disperse in.

The electrodeposition process using this electrodeposition apparatus is performed for each phosphor layer, more specifically, for each color. For example, first, after the first phosphor layer 13 is formed by an electrodeposition method, the second phosphor layer 23 is formed by an electrodeposition method. in this case,
First, the screen panel 31 is placed in an electrodeposition liquid 62 in which a white light-emitting phosphor as a component of the first phosphor layer 13 is dispersed.
Are held and arranged by the electrode / holding portion 63. At this time, the electrode portion of the electrode / holding portion 63 is brought into contact with the lead line portion 16 of the first conductive film 15 on which the first phosphor layer 13 is formed. Thus, the voltage from the power supply 65 is selectively applied only to the first conductive film 15 via the electrode / holding portion 63. Further, the opposing electrode 64 is disposed so as to oppose the first conductive film 15 on which the first phosphor layer 13 is formed.
Then, as shown in FIG. 3, for example, a positive potential is applied to the counter electrode 64 and a negative potential is applied to the first conductive film 15 via the electrode / holding portion 63 and the lead-out portion 16, for example. Perform an electrodeposition process. Thereby, the screen panel 3
On the first inner surface, the first phosphor layer 13 is selectively electrodeposited on the first conductive film 15.

Next, the screen panel 31 is placed and held by the electrode / holding portion 63 in the electrodeposition liquid 62 in which the phosphor powder as a component of the second phosphor layer 23 is dispersed. At this time, the electrode portion of the electrode / holding portion 63 is connected to the lead line portion 2 of the second conductive film 25 on which the second phosphor layer 23 is formed.
6 is contacted. Thus, the voltage from the power supply 65 is selectively applied only to the second conductive film 25 via the electrode / holding unit 63. Further, the opposing electrode 64 is disposed so as to oppose the second conductive film 25 on which the second phosphor layer 23 is formed. Then, as shown in FIG. 3, for example, a positive potential is applied to the opposing electrode 64, and the electrode / holding portion 63 is applied to the first conductive film 15.
Then, for example, a negative potential is applied through the lead line portion 16 to perform the electrodeposition processing of the phosphor. Thus, on the inner surface of the screen panel 31, the second phosphor layer 23 of a desired color is selectively electrodeposited on the second conductive film 25.

When the second phosphor layer 23 is formed of a plurality of phosphor layers having different emission colors (ie, a plurality of phosphor patterns having different emission colors), an electrodeposition process is performed for each color. For example, each of the phosphor layers 23A, 23B, and 23C constituting the second phosphor layer 23 may be represented by blue, red,
In the case of forming with a green phosphor, the screen panel 31 is arranged in the electrodeposition liquid 62 in which the phosphor powder of each color is dispersed, and the electrodeposition process is sequentially performed. At this time, the electrode and holding unit 6
In each electrodeposition process step, the electrode portion 3
A, 23B, and 23C, each conductive film 25A, 2
5B, 25C, each lead wire portion 25A, 25B, 25C
Selectively. Thus, in each electrodeposition process, the voltage from the power supply 65 is selectively applied to only the conductive film to be electrodeposited among the conductive films 25A, 25B, and 25C. In addition, as the blue phosphor powder, for example, Z
nS: Ag or the like can be used. Further, as the green phosphor powder, for example, ZnS: Cu, Al or the like can be used. As the red phosphor powder, for example, Y ₂ O ₂ S: Eu or the like can be used.

After forming each phosphor layer as described above, next, as shown in FIG. 5, each of the lead lines 16, 26 of each of the conductive films 15, 25 is connected to a conductive film made of, for example, a carbon film. The common conductive portion 54A is electrically interconnected to form a common connection portion 54A (step S3). This allows
The conductive films 15 and 25 are electrically interconnected.

Next, a frit sealing step (F / S step)
Thereby, the screen panel 31, the front panel 32 and the funnel 33 are joined (step S4).

Next, the internal conductive film 53 of the funnel 33
And the common connection portion 54A formed in step S3 are electrically connected by applying a carbon film, for example (step S5). As a result, as shown in FIG. 5, a conductive conductive film 54 is provided in a region from each lead wire portion 16, 26 of each conductive film 15, 25 to an end of the internal conductive film 53 on the screen panel 31 side. It is formed. As a result, the conductive films 15 and 25 of the screen panel 31 and the internal conductive film 53 of the funnel 33 are electrically connected. The conductive film 54 for conduction is, for example, 440 ± 20 ° C.
It is fired at about the temperature. Thus, the anode voltage HV can be applied to the first conductive film 15 and the second conductive film 25 via the internal conductive film 53 and the conductive film 54 for conduction. As described above, the flat cathode ray tube 3
0 is produced.

As described above, according to the present embodiment, the conductive films 15 and 25 are formed in portions corresponding to the regions where the phosphor layers 13 and 23 are formed, and the conductive films 15 and 2 are formed.
5, a lead wire portion 1 for applying a voltage
6 and 26 are formed, and then a voltage is selectively applied to each of the lead-out portions 16 and 26 in the electrodeposition solution to form each conductive film 1.
Since the respective phosphor layers 13 and 23 are selectively formed on the layers 5 and 25, the respective phosphor portions 51 and 52 are formed using the same manufacturing method (electrodeposition method). be able to. Thus, the formation of the phosphor screen 50 can be easily performed as compared with the case where the respective phosphor parts 51 and 52 are formed by different manufacturing methods.

[Second Embodiment] Next, a second embodiment of the present invention will be described.
An embodiment will be described. In the following description, the same components as those in the first embodiment are denoted by the same reference numerals, and description thereof will not be repeated. Also,
Descriptions of substantially the same manufacturing steps as in the first embodiment will be omitted as appropriate.

In the first embodiment, the phosphor layers 13 and 23 are formed by using the electrodeposition method. In the present embodiment, the phosphor layers 13 and 23 are formed by using the slurry method.

The flat cathode ray tube 30 according to the present embodiment
The overall flow of the manufacturing process is as shown in FIG. In the manufacturing process shown in FIG. 7, steps S11, S13, S14, and S15 other than step S12 are respectively performed in steps S1, S3, and S15 in the manufacturing process shown in FIG.
4, S5. Hereinafter, the process of step S12 will be mainly described.

In step S12, the first conductive film 15 and the second conductive film 2 formed in step S11 are formed.
5, a first phosphor layer 13 and a second phosphor layer 23 are selectively formed by using a slurry method. In the slurry method, a phosphor slurry composed of a phosphor and a photosensitive binder is applied to a surface on which the phosphor is formed, and then dried,
It performs processes such as exposure and development.

The phosphor forming process using the slurry method is performed for each phosphor layer, more specifically, as in the electrodeposition method.
Perform for each color. For example, first, after forming the first phosphor layer 13, the second phosphor layer 23 is formed. In this case, first, a phosphor slurry containing a white light-emitting phosphor as a component of the first phosphor layer 13 is applied on the first conductive film 15 on which the first phosphor layer 13 is formed. I do. Thereafter, the first phosphor layer 13 is formed on the first conductive film 15 through processes such as drying, exposure, and development. Similarly, for the second phosphor layer 23, a phosphor slurry containing a phosphor of a desired color is applied on the second conductive film 25 on which the second phosphor layer 23 is formed. After that, the second conductive film 25 is dried on the second conductive film 25 through processes such as drying, exposure, and development.
Is formed.

As described above, according to the present embodiment, the conductive films 15 and 25 are formed in portions corresponding to the regions where the phosphor layers 13 and 23 are formed, and then each conductive film is formed by the slurry method. On each of the phosphor layers 13 and 23,
Is selectively formed, so that the phosphor portions 51 and 52 can be formed using the same manufacturing method (slurry method). Thereby, each phosphor part 51,
The formation of the phosphor screen 50 can be performed more easily than when the 52 is formed by a different manufacturing method.

The present invention is not limited to the above embodiments, and various modifications can be made. For example, the present invention
The present invention can be applied not only to a flat cathode ray tube but also to a so-called straight type cathode ray tube in which an electron beam from an electron gun is irradiated perpendicularly to the center of a phosphor screen.

In each of the above embodiments, the icon display area 32B (the second phosphor section 52) is provided below the main video display area 32A (the first phosphor section 51). However, the icon display area 32B may be provided in another area. That is, the icon display area 32B may be provided above, on the left side, or on the right side of the main video display area 32A.
Further, the icon display area 32B may be provided in two or more areas.

[0050]

As described above, claims 1 to 3 are described.
According to the method for forming a phosphor screen according to any one of the above, a conductive film is formed in a portion corresponding to a region where each phosphor layer is formed, and a lead for applying a voltage to each of the conductive films. A line portion is formed, and thereafter, a voltage is selectively applied to each of the lead-out line portions in the electrodeposition solution to form a first phosphor layer on the first conductive film and on the second conductive film, respectively. Since the second phosphor layer and the second phosphor layer are selectively formed, the respective phosphor portions can be formed using the same electrodeposition method. Thereby, the formation of the phosphor screen can be easily performed as compared with the case where each phosphor section is formed by a different method.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing a configuration of a main part of a flat cathode ray tube manufactured by using a method of forming a phosphor screen according to a first embodiment of the present invention.

FIG. 2 is a front view showing the flat cathode ray tube shown in FIG. 2 as viewed from the front (front panel side).

FIG. 3 is a configuration diagram of an electrodeposition apparatus used in the method for forming a phosphor screen according to the first embodiment of the present invention.

FIG. 4 is a front view showing a structure of a phosphor screen manufactured using the phosphor screen forming method according to the first embodiment of the present invention before electrodeposition of a phosphor.

FIG. 5 is a front view showing a structure of a fluorescent screen of a flat type cathode ray tube manufactured by using the method for forming a fluorescent screen according to the first embodiment of the present invention.

FIG. 6 is a flowchart for explaining a flat cathode ray tube manufacturing process including a phosphor screen forming method according to the first embodiment of the present invention.

FIG. 7 is a flowchart for explaining a flat cathode ray tube manufacturing process including a phosphor screen forming method according to a second embodiment of the present invention.

FIGS. 8A and 8B are explanatory diagrams showing a display method of a cathode ray tube, in which FIG. 8A shows a conventional flat cathode ray tube capable of only monochrome display, and FIG. 1 shows a flat-type cathode ray tube which enables icon-like color display.

[Explanation of symbols]

13: first phosphor layer, 15: first conductive film, 16, 2
6. Leader line part, 23 second phosphor layer, 25 second
30, a flat cathode ray tube, 31 a screen panel, 32 a front panel, 32A a main video display area, 32B an icon display area, 33 a funnel section,
35: electron gun, 41: main image, 42: icon image, 5
0: phosphor screen, 51: first phosphor section, 52: second phosphor section, 53: internal conductive film, 54: conductive film for conduction, 54A
... common connection part, 61 ... electrodeposition tank, 62 ... electrodeposition liquid, 63 ... electrode and holding part, 64 ... counter electrode, 65 ... power supply.

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 5C028 FF03 FF08 FF16 5C036 EF02 EF07 EG04 EG50

Claims (3)

[Claims] A first phosphor layer on which a first phosphor layer is uniformly provided;
And a second phosphor portion provided with a second phosphor layer formed of at least one phosphor pattern having a predetermined shape, the method comprising: Forming a first conductive film over the entire formation region of the first phosphor portion, and forming a first lead-out portion for applying a voltage to the first conductive film; A second conductive film having the same shape as the phosphor pattern is formed at a position where the second phosphor layer is formed in a formation region of the phosphor portion, and a voltage is applied to the second conductive film. Forming a second lead-out portion on the first conductive film and the second conductive film by selectively applying a voltage to each of the lead-out portions in an electrodeposition solution. The first phosphor layer and the second phosphor layer are selectively A phosphor screen formed method which comprises a step of wearing formation. 2. A region other than a region where each of the conductive films and each of the lead lines is formed is covered with a mask,
2. The method for forming a phosphor screen according to claim 1, wherein said conductive films and said lead lines are formed simultaneously and collectively. 3. The method according to claim 1, further comprising: after forming each of the phosphor layers on each of the conductive films, forming a conductive conductive film for electrically interconnecting the respective lead-out lines. The method for forming a phosphor screen according to claim 1, wherein: