JPH0223968B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing an anode substrate for a fluorescent display tube, and more particularly to a method for manufacturing an anode substrate for a graphic fluorescent display tube for high-density display.

Fluorescent display tubes display images at low voltage by projecting electrons emitted from a heated filament-shaped cathode onto an anode whose upper surface is coated with phosphor and selectively given an anode potential. It has many features such as sufficient brightness, low power consumption, ability to be driven directly by LSI, etc., and the ability to emit light in a variety of colors depending on the type of phosphor. Therefore, they are often used as display devices for various electronic devices and electric machines.

Recently, there has been a demand for fluorescent display devices to display not only numbers and characters but also arbitrary figures, images, etc., and this has led to the development of graphic fluorescent display tubes. Furthermore, in order to display more precisely, it is desired to increase the density of the display.

Fluorescent display tubes that display graphics, characters, etc. with high density are made of, for example, anode conductors that are divided into stripes and formed in parallel on an insulating substrate, and are arranged in a direction that intersects the many anode conductors. There is a type of graphic fluorescent display tube having an electrode structure in which a large number of control electrodes are arranged in a matrix.

By the way, conventionally, the lead frame connected to the anode conductor has a comb shape, and when forming the vacuum container by overlapping each lead end of the lead frame with the individual anode conductor and vacuum sealing, the vacuum container is constructed. The lead frame was sandwiched and fixed between the base plate and the side plate, and the lead ends were electrically connected to the individual anode conductors.

However, with the demand for high-density display as mentioned above, the arrangement pitch of the anode frame has become extremely narrow (for example, 0.3 mm), so the lead pitch of the lead frame must also be reduced accordingly. When the value becomes small, it is difficult to accurately position the lead end to each anode conductor and connect it securely with strong adhesive strength using the conventional method described above.This is particularly important to prevent positioning errors in the manufacture of fluorescent display tubes for high-density displays. This also hindered the improvement of connection workability.

This invention has been made in view of the above points. In other words, the present invention makes it possible to accurately position the lead portion and connect reliably and easily with strong adhesive strength even when the anode conductor is formed with narrow pitch intervals for high-density display, thereby preventing poor positioning and making the connection work easier. It is an object of the present invention to provide a method for manufacturing an anode substrate for a fluorescent display tube, which can improve performance.

Therefore, in order to achieve this object, the method of the present invention involves forming a plurality of strip-shaped anode conductors at predetermined pitch intervals on an insulating substrate, and alternately forming one strip of each anode conductor on the opposite side. A process of forming wide anode terminals at each end, a process of applying a conductive adhesive to each of the anode terminals arranged in parallel to form a fusion terminal, and a process of forming a fusion terminal with a pitch twice as large as that of the anode conductor. A lead frame is positioned on the insulating substrate, in which both ends of the lead portions arranged in parallel are connected to the connection frame, and at least one end of the lead portion is a half-etched portion having a smaller cross-sectional shape than the lead portion. , positioning the vicinity of the other end of the half-etched portion on the fusion terminal, and heating a part of the lead portion closer to the other end than the fusion terminal by sandwiching it between the substrate and the side plate via a sealing material;・A step of fixing, a step of applying a crystallized glass adhesive onto the lead part near the anode terminal part and then heating it to reinforce the fixation of the lead part, and cutting the lead part at the half-etched part. removing an unnecessary connection frame of the lead frame, connecting the lead portion connected to the anode terminal portion to a power source, and depositing a phosphor layer on the anode conductor by electrodeposition. It is a feature.

Hereinafter, one embodiment of the present invention will be described with reference to the drawings.

1A and 1B are a plan view and a cross-sectional view of a matrix-type fluorescent display tube manufactured by the method of manufacturing an anode substrate according to the present invention, and this fluorescent display tube is divided into stripes on an anode substrate. The display device has an electrode structure in which a display matrix is formed by anode conductors formed in parallel and a plurality of control electrodes stretched in a direction intersecting the plurality of anode conductors.

In the figure, 1 is an anode substrate made of an insulating material such as glass or ceramics, and this anode substrate 1 is a so-called front-emission type in which light emission from a phosphor layer is observed through the anode substrate 1. Must be made of insulating material. As shown in FIGS. 2 and 3, on the inner surface of this anode substrate 1, a plurality of anode conductors 2 made of a conductive metal film, such as an Al film, are formed at a predetermined pitch interval P by a photoetching method or the like. are formed in parallel. A wide anode terminal portion 2a is continuously formed at one end of each anode conductor 2, and the anode terminal portions 2a of adjacent anode conductors 2 are alternately located on opposite sides. In the case of the front emission type, the anode conductor 2 must be formed of a transparent conductive film or a mesh-shaped conductive metal film.

On the other hand, as shown in FIG. 4, the front plate 3 of FIGS. 1A and 1B has a cathode mounting frame 4 attached to its inner surface with a glass adhesive (for example, fritted glass). Anchors 4a and supports 4b are provided at opposite positions of the cathode mounting frame 4, and a filament-shaped cathode 5 is stretched in a direction substantially perpendicular to the anode conductor 2 between each anchor 4a and support 4b. has been done. In addition, a separate glass sealing material 6 is provided on the outer periphery of the four sides of the inner surface of the front plate 3.
(for example fritted glass) is arranged by a printing method.

Next, the lead frame 7 connected to the anode conductor 2 on the anode substrate 1 will be explained. The lead frame 7 is formed by etching a conductive metal flat plate as shown in FIG. It is composed of a large number of lead portions 9 which are connected and arranged in parallel at a constant pitch interval R, that is, at a pitch interval twice that of the anode conductor. The pitch interval R of this lead part 9 is twice the predetermined pitch interval P of the anode conductor 2, that is, each lead part 9 corresponds to the position of each anode terminal part 2a, 2a of the anode conductor 2. It is set as follows. Further, each of the lead portions 9 and the left and right connecting portions 8c and 8d are half-etched along the half-etched line L-- shown in FIG.
It was applied along L, and each portion was thinner than the plate thickness of lead frame 7. Alternatively, the half-etched portion 10 has a narrower plate width.

Furthermore, a small hole 8 for positioning is provided in the outer connecting portion 8a.
A plurality of e are provided.

Next, the anode substrate 1, the front plate 3, and the upper and lower, left and right side plates 11 and 12 made of transparent or opaque insulating material are placed in a vacuum container (see Fig. 1 A and B). The linear electrodes 13 arranged in a suspended manner will be explained. As shown in FIG. 6, the linear electrode 13 has a thin linear electrode part 13a and wide connecting parts 13b and 13c of different lengths formed at both ends of the electrode part 13a. 1
3 are arranged in parallel on the frame 14 at a predetermined pitch interval S, and each linear electrode 13 and the frame 14 form an electrode frame F. In addition, the frame 14
A small hole 14a for attaching the electrode frame F is provided near the connecting portions 13b and 13c.

As shown in FIG. 7A, the anode substrate 1 is placed on the positioning plate B provided with the lead frame positioning pins 15 and the positioning protrusions 16 for the anode substrate 1, and the anode substrate 1 is positioned as described above. Position it closer to the protrusion 16 side. Then, a conductive adhesive layer made of a conductive metal (for example, Ag) and a low melting point glass (for example, fritted glass) is attached on the anode terminal portion 2a of each anode conductor 2 on the anode substrate 1 by a printing method to form a fusion terminal. 17, and
As shown in FIGS. 3 and 7A, a glass sealing material 18 (for example, frit glass) is printed around the four sides of the anode substrate 1, and an exhaust pipe H is attached.

Next, the small hole 8e for positioning the lead frame 7
are engaged with the corresponding positioning pins 15 so that the inner connecting portions 8b are superimposed on the anode substrate 1, and each lead portion 9 is positioned on the corresponding anode conductor 2, and the intermediate portion of each lead portion 9 is are positioned on the corresponding fusion terminals 17. Next, side plates 1 are placed on top and bottom of the glass sealing material 18 that has already been formed.
1 and 11, and press the side plates 11, 11 to a fixed position on the anode substrate 1 while sandwiching the portion of each lead portion 9 closer to the outer connecting portion 8a than the intermediate position. Then, as shown in FIG. 7c, the anode terminal portion 2
After fusion, an insulating crystallized glass adhesive 19, such as Pyroceram glass adhesive, which has a softening point higher than the heating temperature when assembling the fluorescent display tube, is applied in a strip shape near a, and the glass Sealing material 18
At the same time, each lead portion 9 is fixed to the anode substrate 1 and the anode terminal portion 2a by heating and melting. Here, each lead part 9 of the lead frame 7 has an intermediate part extending from the part pressed by the side plate 11 to the fusion terminal 17, and the connection part of the lead part 9 to the fusion terminal 17 when fixing the above. A more stable connection can be obtained by forming the connector in advance into a curved shape that applies a spring force to the connector.

Furthermore, as shown in FIG. 7c to FIG. 7D, the unnecessary inner connecting portion 8b is removed from the half-etched portion 1.
The anode conductor 2 is bent from zero and cut and removed, and a phosphor layer 20 is formed on each anode conductor 2 by electrodeposition.
Further, the portion of the outer connecting portion 8a indicated by the dashed line is cut and removed, leaving the lead portion 9 necessary as a connection terminal line with an external control circuit.

Spacers 21, 21 were temporarily fixed to the inner surface of the anode substrate 1 produced in this way through a glass adhesive at the left and right positions as shown in FIGS. 1A and B, and the spacers 21, 21 as shown in FIG. The electrode frame F is placed on the spacers 21, 21 with tension applied to the electrode frame F in the longitudinal direction of the electrode portion 13a by an electrode sealing jig (not shown). Then, the side plates 12, 12 at the left and right positions are placed and temporarily fixed on the glass sealing material 18 of the anode substrate 1 with the electrode frame F in between, and on the side plates 11, 12 at the top, bottom, left and right positions, The front plate 3 shown in FIG. 4 is placed facing downward so that the cathode 5 faces the anode conductor 2. In this case, at least one of the surfaces where the side panels 11 and 12 come into contact with each other is coated with a glass adhesive in advance, and is pressed with the glass adhesive between them. After that, in this state, it is pressed and fixed from above and below with clips, etc., placed in a furnace, heated and sealed, and further sealed by exhaust treatment through the exhaust pipe H, as shown in Fig. 1A. A vacuum container is formed with a linear electrode 13 as a control electrode stretched without slack inside the vacuum container, and the electrode frame F led out of the vacuum container is connected to the external frame 14, leaving a predetermined connection part 13b. Cut and remove unnecessary parts.

Therefore, during the sealing process of heating to form a vacuum container, the crystallized glass adhesive 19 to which each lead portion 9 was previously bonded has a softening point higher than the heating temperature during sealing. There is no risk of poor contact between each lead portion 9 and the fusion terminal 17 of the anode terminal portion 2a, and they are bonded with strong adhesive strength by the crystallized glass adhesive 19 and the fusion terminal 17.

By the way, the present invention is not limited to the embodiments described above, and can be implemented in various modifications without changing the gist thereof. , the outer connecting portion can be easily cut and removed.

As explained above, in the method for manufacturing an anode substrate for a fluorescent display tube according to the present invention, the lead portions are arranged at regular intervals and both ends are connected by a connecting portion, and at least one end of the lead portion is formed in a thin plate shape. forming a lead frame, connecting it to an anode conductor on an insulating substrate, forming a conductive adhesive layer on the substrate, and positioning an intermediate position of the lead portion of the lead frame on the conductive adhesive layer; The phosphor layer is applied to the anode conductor after it is sandwiched between the substrate and side plate and heated and fixed together with the sealing material, so even anode conductors formed with narrow pitch intervals for high-density display can be used. Compared to conventional lead frames, the lead part can be positioned more accurately and fixed with strong adhesive strength, reliably, and easily, which prevents poor positioning of the lead frame and improves stable workability. Great effects can be obtained.

[Brief explanation of drawings]

FIGS. 1A and 1B are a plan view and a cross-sectional view of a matrix-type fluorescent display tube manufactured by the method of manufacturing an anode substrate according to the present invention, and FIG. 2 is a plane view showing the pattern of the anode conductor on the anode substrate. 3 is a side view of the anode substrate, FIG. 4 is a plan view of the front plate, FIG. 5 is a perspective view of the lead frame, and FIG. 6 is a side view of the anode substrate.
The figure is a perspective view of an electrode frame for a control electrode, and FIGS. 7A, B, C, and D are explanatory views showing the manufacturing process of an anode substrate. DESCRIPTION OF SYMBOLS 1... Anode substrate, 2... Anode conductor, 2a... Anode terminal part, 3... Front plate, 5... Cathode, 6, 18
...Glass sealing material, 7...Lead frame, 8a
...Outer connecting part, 8b...Inner connecting part, 9...Lead part, 10...Half etching part, 11,1
2... Side plate, 13... Linear electrode as a control electrode, 17... Fusion terminal consisting of a conductive adhesive layer,
19... Crystalline glass adhesive, 20... Phosphor layer.

Claims (1)

[Claims] 1. Forming a plurality of strip-shaped anode conductors at predetermined pitch intervals on an insulating substrate, and forming a wide anode terminal portion at one end of each anode conductor on the opposite side alternately. a step of applying a conductive adhesive to each of the anode terminals arranged in parallel to form a fusion terminal; positioning a lead frame on the insulating substrate, in which at least one end of the lead portion is a half-etched portion having a smaller cross-sectional shape than the lead portion;
The vicinity of the other end of the half-etched portion is positioned on the fusion terminal, and a part of the lead portion closer to the other end than the fusion terminal is sandwiched between the substrate and the side plate via a sealing material and heated. a fixing step; a step of applying a crystallized glass adhesive onto the lead portion near the anode terminal portion and then heating it to reinforce the fixation of the lead portion; and cutting the lead portion at the half-etched portion. It is characterized by the step of removing an unnecessary connecting frame of the lead frame, connecting the lead part connected to the anode terminal part to a power source, and depositing a phosphor layer on the anode conductor by electrodeposition. A method for manufacturing an anode substrate for a graphic fluorescent display tube.