JPH04289643A - Flat type display device - Google Patents

Abstract

PURPOSE:To prevent the charge-up on an inner wall of an electron passing part, enhance brightness and reduce a dispersion of the brightness in such a way that the passing quantity of electron beam is not influenced by the quantity of charge, and enhance workability and reliability. CONSTITUTION:The inner substrate exposed part M of an electron passing part (electron passing hole 7) between respective tips of extruded parts 9m and 10m is indented such that its diameter D2 is larger than that D1 of the other part. An insulating substrate 8 is comprised by clading two substrates of the same thickness. Further, the insulating substrate 8 is composed of substrates 8h and 8i, of the same thickness on both sides, and a central substrate 8j of the thickness corresponding to the substrate exposed part M.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flat display device using electron beams.

0002

[Prior Art] FIG. 7 shows, for example, Japanese Patent Application Laid-Open No. 63-184239
1 is a perspective view showing a part of a conventional flat display device as shown in the above publication, in which 1 is a linear hot cathode as an electron emission source that is connected to a support and emits electrons when energized; 2 is a linear hot cathode; This is a perforated cover electrode with an elliptical cross section that covers the upper surface of the linear hot cathode 1 . This perforated cover electrode 2 has a large number of small holes 3 for passing electrons, and electrons are extracted from the linear hot cathode 1 by applying an appropriate potential. 4 is coated with dots on the inner surface of the phosphor 5, which serves as three kinds of light emitters that emit red, green, and blue light when excited by the electrons extracted by the perforated cover electrode 2. As shown in the figure, this is a front glass as a front plate on which an aluminum film 12 is further formed to provide conductivity.By applying a voltage of about 10 to 30 KV to this aluminum film 12, electrons is accelerated and excites the phosphor 5 to emit light. Reference numeral 6 denotes a control electrode section which is interposed between the front glass 4 and the linear hot cathode 1, and which passes or blocks electrons drawn out by the perforated cover electrode 2 and directed toward the front glass 4, as shown in FIG. As shown in the exploded configuration diagram, there is an insulating substrate 8 having electron passing holes 7 as electron passing portions corresponding to the pixels on the front glass 4, and an insulating substrate 8 having electron passing holes 7 as electron passing portions corresponding to the pixels on the front glass 4, and an insulating substrate 8 having an electron passing hole 7 on the lower surface of the insulating substrate 8 corresponding to each row of pixels. A first control electrode group 9 consisting of strip-shaped metal electrodes 9a arranged in an array and having an electron passage portion 9b, and a first control electrode group 9 having an electron passage portion 10b and corresponding to each row of pixels on the upper surface of the insulating substrate 8. and a second control electrode group 10 consisting of strip-shaped metal electrodes 10a arranged in the same manner. Each of the metal electrodes of the first and second control electrode groups 9 and 10 is made of a strip-shaped metal, and the electron passing portions 9b and 10b are formed on the insulating substrate 8, as shown in an enlarged view in FIG. A large number of small holes 11 are formed in portions corresponding to the electron passage holes 7 to form a mesh shape.

Next, the operation will be explained. Linear hot cathode 1
The thermoelectrons emitted from the hot cathode 1 are extracted by the perforated cover electrode 2, and then a wire is connected to one of the first control electrode group 9 consisting of metal electrodes 9a arranged in a direction perpendicular to the linear hot cathode 1. By applying a positive potential of approximately 20 to 40 V to the potential of the hot cathode 1, the thermoelectrons are attracted to this electrode and reach the control electrode portion 6. Here, by adjusting the elliptical columnar shape of the perforated cover electrode 2, the position of the first control electrode group 9, and the voltage applied to each metal electrode 9a, it is possible to select any one of the first control electrode group 9. The electron flow density on the front surface of the metal electrode 9a of the book is made almost uniform.

[0004] The operation of the control electrode section 6 is not explained in the above-mentioned Japanese Patent Application Laid-Open No. 184239/1982, but for example, Japanese Patent Application Laid-Open No. 172642/1982 and Japanese Patent Application Laid-open No. 1987-1-
It is similar to a general matrix type display as described in Japanese Patent No. 126688, etc., and is as follows. That is, as described above, one of the first control electrode groups 9
If only one metal electrode 9a has a positive potential and the others have a 0V or negative potential, the thermoelectrons emitted from the linear hot cathode 1 are attracted only to this one metal electrode 9a that has a positive potential, and the metal Each electron passing portion 9b of the electrode 9a
The electrons pass through the electron passage hole 7 of the insulating substrate 8. The electrons that have entered the electron passage hole 7 do not all pass through to the front glass 4 side, but instead, for example, 40 to 1 of the second control electrode group 10 arranged above the electron passage hole 7
Electrons pass through only the electron passing portion 10b of the metal electrode 10a to which a potential of 00V is applied, and do not pass through the other electron passing portions 10b of the metal electrode 10a to which a potential of 0V or negative is applied. Stops at. Therefore, of the first control electrode group 9, one of the on-states to which a positive potential is applied is
Electrons pass only through the electron passing hole 7 at the intersection between the main metal electrode 9a and the metal electrode 10a of the second control electrode group 10 to which a positive potential is applied. Then, the passing electrons cause the phosphor 5 at the pixel position corresponding to the electron passing hole 7 to emit light, and a screen display is performed. Therefore, by controlling the potential application to each metal electrode 9a, 10a so that the above-mentioned intersection corresponds to a desired position, a desired image display can be performed.

As shown in FIG. 10, the electron passing portions 9b and 10b of each control electrode 9 and 10 corresponding to the electron passing hole 7 of the insulating substrate 8 are formed into a mesh shape with a large number of small holes 11. This means that when the electron passing section 9b, 1
0b needs to generate a potential that blocks electrons as a whole, and by applying a small negative potential of 0V to several tens of volts to each control electrode group 9, 10, it is possible to block the passage of electrons. It is.

[0006]

In the conventional flat display device as described above, when the electron beam passes through the electron passing hole 7 of the insulating substrate 8, the inner wall surface of the electron passing hole 7 is charged up and the electron There were problems in that the amount of beam passing was affected by the amount of charge, resulting in lower brightness, and brightness varied widely from dot to dot. This invention was made to solve the above-mentioned problems, and it prevents the charge-up phenomenon, improves workability and reliability, and improves brightness.
An object of the present invention is to obtain a flat display device that enables reduction of luminance variations.

[0007]

[Means for Solving the Problems] The first invention provides a protrusion 9
Electron passage part between the tips of m and 10m (electron passage hole 7
) is recessed so that its diameter D2 is set larger than the diameter D1 of the other parts.

[0008] In addition to the first invention, the second invention is such that the insulating substrate 8 is constructed by laminating two substrates 8m and 8n of the same thickness.

In addition to the first invention, a third invention is such that the insulating substrate 8 is formed of substrates 8h and 8i on both sides having the same thickness and a central substrate 8j having a thickness corresponding to the exposed portion M of the substrate. This is what I did.

0010

[Operation] In the present invention, the electron beam
The electrons pass through the electron passage section (electron passage hole 7) without directly colliding with the electrons, thereby avoiding a charge-up phenomenon in the exposed portion M of the substrate.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Examples of the present invention will be described below with reference to the drawings. FIG. 1 is a perspective view of a portion of a flat display device according to an embodiment of the present invention, and numerals 1 to 5 are similar to the conventional example described above. Reference numeral 6 denotes a control electrode section interposed between the front glass 4 as a front plate and the linear hot cathode 1 as the electron emission source, and a large number of electron passing holes as electron passing sections corresponding to each pixel of the screen. 7, which passes or blocks electrons extracted by the perforated cover electrode 2 and directed toward the front glass 4. FIGS. 5 and 6 are enlarged perspective views showing the control electrode section 6 as a partially cut section. FIG. 5 is a view from above, and FIG. 6 is a view from below. 13 is a conductive substrate made of stainless steel or iron, and has an electron passing hole 7 through which electrons pass; 14 is this conductive substrate 13;
An insulating film made of alumina, silica, etc. is formed on the entire surface including the inner wall surface of the electron passage hole 7, and an insulating substrate 8 is constituted by these. A metal electrode 9a made of a conductive film such as nickel is coated on the lower surface of the insulating substrate 8 by dividing it into a plurality of parts so as to correspond to each row of electron passing holes 7 while forming an exposed part 9c of the insulating substrate 8. Similarly, a first control electrode group 10 is formed on the upper surface of the insulating substrate 8 at a substrate exposed portion 10.
The second control electrode group is made up of a metal electrode 10a made of a conductive film that is divided into a plurality of parts and coated so as to correspond to each row of the electron passage holes 7 while forming a conductive film. These first
, the metal electrodes 9a, 10a of the second control electrode groups 9, 10 are coated up to the inner wall surface of the electron passage hole 7. The first and second control electrode groups 9 and 10 are electrically isolated by forming a substrate exposed portion 18 where the conductive film is cut and the insulating film 14 is exposed. 1,
Metal electrodes 9a and 1 of second control electrode groups 9 and 10, respectively
In 0a, adjacent columns or rows are electrically isolated by substrate exposed parts 9c and 10c, and with this configuration, each column or row is independently connected to the metal electrodes 9a and 10a. Another potential can be applied.

In manufacturing the control electrode section 6, a stainless steel plate with a thickness of 0.5 mm is used as the conductive substrate 13, and an electron passage hole 7 of 0.4 mm is formed using, for example, an etching method. Thereafter, a silica layer with a thickness of about 30 μm is formed as the insulating film 14 using, for example, a dipping method. Thereafter, using techniques such as electroless plating and masking, the substrate exposed portions 9c, 10c, 18, ie,
While holding the exposed portion M of the substrate, metal electrodes 9a and 10a made of a nickel metal film with a thickness of approximately 2 μm are formed, and the first
, forming a second control electrode group 9, 10. As shown in the cross-sectional structural diagram of FIG.
The width of the second control electrode group 9 and 10 was both 0.2 mm, and the width of the substrate exposed portion 18 was maintained at 0.1 mm.

Furthermore, dots of the phosphor 5 on the front glass 4,
The pitch is formed to correspond to the electron passage holes 7 of the control electrode section 6.

As shown in the perspective view of FIG. 1, a convergence electrode plate 19 for converging electrons passing through the control electrode part 6 is disposed between the front glass 4 and the control electrode part 6. This focusing electrode plate 19 is connected to the second control electrode group 10 of the control electrode section 6.
It is made of a stainless steel plate with a thickness of 0.45 mm and has holes of 0.45 mm arranged at the same pitch as the electron passing holes 7 of the conductive substrate 13, and is created by etching or the like. It is something. Note that the lower surface of the focusing electrode plate 19 and the surface of the control electrode section 6 that is in contact with the second control electrode group 10 are covered with an insulating layer such as polyimide resin.
A different potential from that of the control electrode group 10 can be applied.

In the flat display device having such a configuration, as in the above conventional example, the first and second control electrode groups 9,
By applying a potential to control the passage of electrons to 10, it is possible to control the light emission of the phosphor 5 in each pixel and display a desired image. First and second control electrode groups 9, 10
The on-off operation was confirmed by setting the voltage applied to the same level as in the conventional example, and the light emitting state of the phosphor 5 was observed and compared, and as a result, sufficient display function was confirmed.

In particular, in order to ensure the off-state, it is necessary to generate a sufficient electric field to prevent electrons from passing through the electron passing hole 7, but as mentioned above, the protrusion 9m
, 10m on the inner wall surfaces of the electron passing sections 9b, 10b is effective in easily generating such an electric field. It is desirable that the diameter be 1/4 or more, particularly 1/2 or more of the diameter of the electron passing portions 9b, 10b.

However, in the structure of the prior application, the substrate exposed portion 18 of the electron passing hole 7 receives the electron beam, and this substrate exposed portion M becomes negatively charged or positively charged due to secondary electron emission. The charge-up phenomenon in which the battery is charged to a certain potential could not be avoided.

FIG. 2 shows one control electrode section 6 according to an embodiment of the present application.
FIG. 2 is an embodiment in which the insulating substrate 8 is composed of a single substrate, and FIG. 3 is an embodiment in which the insulating substrate 8 is composed of two substrates 8m and 8n stacked one on top of the other. and
FIG. 4 shows an embodiment in which the insulating substrate 8 is constructed by stacking three substrates 8h, 8i, and 8j.

In FIG. 2, the difference from the previous application is that the electron passing hole 7 and the electron passing portions 9b, 10b have a diameter D of the substrate exposed portion M.
2 is made larger, and the inner wall is constructed of parts having different inner diameters D1 and D2, and has a structure where D1<D2, and protrusions 9m and 10m are formed on the inner wall of the D1 part, The D2 portion is composed of a substrate exposed portion M. Therefore,
The exposed portion M of the substrate is almost never directly bombarded by the electron beam, so that the above-mentioned charge-up that obstructs the passage of the electron beam can be avoided, and the brightness of the display device can be improved.

FIG. 3 shows two parts in which the insulating substrate 8 is divided at a portion D2.
It has a structure in which two substrates 8m and 8n are stacked on top of each other. Therefore, it is easy to reliably process the structure of the D2 portion, and the D1 portion can be easily formed by a highly reliable method such as vapor deposition.

FIG. 4 shows an insulating substrate 8 having a portion D1.
One board 8j having two boards 8h and 8i and a D2 section
The structure consists of three layers stacked one on top of the other. In this case, since the exposed substrate portion M is composed of a single insulating substrate 8j, the structural dimensions, the accuracy of conductive film formation, and the workability are further improved, and the reliability is also improved.

In the above embodiment of the present invention, adhesive 33 is used in FIGS. 3 and 4, but other means such as bonding may be used, or means for fixing with a fixed portion of insulating substrate 8 may be used. good.

[0023]

As described above, according to the first invention, the substrate exposed portion M on the inner surface of the electron passing portion (electron passing hole 7) between the tips of the protruding portions 9m and 10m is recessed, and its diameter is reduced. D2
Since the diameter D1 is set larger than the diameter D1 of other parts, when the electron beam passes through the electron passage part (electron passage hole 7), charge-up on the inner wall surface of the electron passage part (electron passage hole 7) is prevented. This has the effect that the amount of electron beam passing is not affected by the amount of charge, the brightness is not reduced, and variations in brightness from dot to dot can be reduced.

According to the second invention, the insulating substrate 8 is formed by bonding two substrates 8m and 8n of the same thickness, and according to the third invention, the insulating substrate 8 is formed by bonding two substrates 8m and 8n of the same thickness. Since it is formed by the substrates 8h, 8i on both sides and the substrate 8j in the center having a thickness corresponding to the exposed portion M of the substrate, there is an effect that workability and reliability can be improved.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of a portion of a flat display device according to an embodiment of the present invention.

FIG. 2 is a cross-sectional structural diagram of a control electrode section according to an embodiment of the first invention.

FIG. 3 is a cross-sectional structural diagram of a control electrode section according to an embodiment of the second invention.

FIG. 4 is a cross-sectional structural diagram of a control electrode section according to an embodiment of the third invention.

FIG. 5 is an enlarged perspective view from above showing a control electrode section of a prior application related to the present invention as a partially sectioned section.

FIG. 6 is an enlarged perspective view from below showing a control electrode section of a prior application related to the present invention as a partially sectioned section.

FIG. 7 is a partial perspective view of a conventional flat display device.

FIG. 8 is a partially enlarged perspective view of a conventional flat display device.

FIG. 9 is an exploded configuration diagram of a conventional control electrode section.

FIG. 10 is an enlarged view of a conventional metal electrode.

[Explanation of symbols]

1 Linear hot cathode 4 Front glass 5 Phosphor 6 Control electrode section 7 Electron passage hole 8 Insulating substrate 8h, 8i, 8j, 8m, 8n Substrate 9 First control electrode group 10 Second control electrode group 9a, 10a Metal Electrodes 9b, 10b Electron passage parts 9m, 10m Projection part M Substrate exposed part

Claims (3)

[Claims] Claim 1: a light emitting body provided on the inner surface side of a front plate of a sealed container; an electron radiation source that emits electrons to the light emitter; An insulator comprising a control electrode section interposed between the control electrode section and the control electrode section, having strip-shaped metal electrodes on both sides that intersect with each other, and an electron passage section consisting of a hole that vertically penetrates the intersection section. In a flat display device comprising a substrate, in which each of the metal electrodes is provided with a protrusion that protrudes inward along an inner wall of the electron passage section, an exposed portion of the substrate on the inner surface of the electron passage section between the tips of the protrusion; A flat display device characterized by having a recessed portion and a diameter larger than other portions. 2. The flat display device according to claim 1, wherein the insulating substrate is constructed by bonding two substrates of the same thickness. 3. The planar type according to claim 1, wherein the insulating substrate is formed of substrates on both sides having the same thickness and a substrate in the center having a thickness corresponding to the exposed portion of the substrate. Display device.