JPS59119658A - Fluorescent character display tube - Google Patents

Abstract

PURPOSE:To improve brightness of a display tube in which a display panel is constructed en bloc with a driving circuit by preparing an electrode which drives the display part through the driving circuit and an external electrode which drives the direct display part for the purpose of aging. CONSTITUTION:The display part 6 having a wiring film 2, an insulating film 3, a segment electrode 4 and a phosphor layer 5 as well as a control electrode 11 and a cathode 12 are prepared on a substrate 1, while preparing a driving circuit 14 including a CMOSLSI15 for a quartz control clock in order to form a display tube of COS structure. Thereby, the wiring film 2 is branched in two, whereby one is extended to the LSI15 while the other is extended to the plural conductive faces 31 in order to connect the conductive face part 31 to a terminal leading-in wire 32 to become a separate electrode through the contact part 34 and the spring part 33. Accordingly, aging can be performed safely at the sufficiently high voltage, while improving the level of brightness by making it needles to force the high voltage to pass through the driving circuit part 14 while using the leading-in wire 32.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a fluorescent display tube, particularly a fluorescent display tube in which a display panel and a driving circuit are integrally formed.
The present invention relates to a fluorescent display tube having a structure of s J (hereinafter referred to as COG).

As a conventional fluorescent display tube having a COG structure, there is provided a structure as shown in FIGS. 1 and 2, a cutaway plan view of the main part and a cross-sectional view taken along the line A-A. That is, to explain this conventional example, in Figure 2, 1rs
2. A plurality of wiring coatings laminated and deposited on the upper surface of a substrate IA made of glass, which is an anode substrate that also serves as a drive circuit forming board. It is equipped with an insulated M3° segment electrode 4, a phosphor layer 5, etc., and the plurality of segment electrodes 4 having this phosphor layer 5 constitute an anode display m6 for displaying patterns such as numbers, By arranging a plurality of anode display sections 6 in parallel, a plurality of digits, etc. can be selectively displayed.

The wiring coating 2 electrically connects adjacent common segment electrodes 4 through connection holes 7 provided in the insulation coating #3, and is further extended to the substrate IB as an external drive circuit wr connection electrode. Further, a mesh-like control electrode 11 and a cathode 12 are arranged to face each anode display section 6, and are extended to the top of the substrate 1B through a wiring coating 2. Anode display section 6° control electrode 11. On the anode substrate IA having the cathode 12, etc., an upper plate 13 made of transparent glass or the like is disposed at least at the upper window portion, and the peripheral edge of the upper plate 13 is made airtight with a sealing material 22 such as low-melting frit glass. The drive circuit 14 formed on the substrate IB will be described next. Regarding this conventional example, the crystal control clock CM
One O8LS115 chip is mounted on the board IB. The CMO8LSI chip 15 is die-bonded onto the substrate IB using a conductive or insulating adhesive 16.

Subsequently, wire bonding is performed to connect the electrodes on the chip 15 and the pad portions 17 formed on the wiring film 2. This is connected using a gold wire 18, for example, by a thermosonic method. Furthermore, a silicone or epoxy resin is coated as a protective film 19 over these, and the drive circuit 1 is coated with silicone or epoxy resin.
4 is completed.

Such die bonding and wire bonding work is performed after the exhaust work process in the fluorescent display tube manufacturing process, and this is because the adhesive 1 used for die bonding is
Determined from 6 heat-resistant special orders. Furthermore, since the work is carried out after the evacuation process, it is important to perform the bonding at as low a temperature as possible in order to reduce the amount of gas released inside the fluorescent display tube.

It was made like this. In the conventional structure, the external terminal 20
By attaching a crystal oscillator (not shown) to the unit and connecting it to a 12V DC power supply, a statically driven clock display can be performed.

However, in conventional fluorescent display tubes having such a COG structure, poor brightness often occurs. The reason for this was that the activation of the phosphor was non-luminous.

Activation (aging) of a fluorescent display tube Operates for several tens of hours by applying a voltage between the anode coated with a phosphor layer, the control electrode that controls the electron flow, and the filament electrode coated with an electron emissive material. A method is being taken to do so.

As is well known, the activation of the 4A element is carried out by electron bombardment stimulation from a filament, but in order to increase the luminous efficiency it is necessary to apply a somewhat high voltage.1. Apply voltage. At this time, in order to reduce the influence of gas poisoning, the filament voltage is generally aged by applying a voltage 1 to 2 times higher than the rated voltage.

However, in the fluorescent display tube with the COG structure shown in Figures 1 and 2, in order to perform aging while operating the mounted 0MO8LSI, a voltage sufficiently higher than the rated voltage of the fluorescent display tube is applied to achieve a high brightness level. The problem was that there was no active method to obtain this. This is due to the fact that the withstand voltage of T and SI mounted on this device is generally low. Also, if a low voltage is applied, a long aging period is required.
This was a huge problem in terms of mass production and economy.

The present invention solves the conventional problems as described above.
It is an object of the present invention to provide a fluorescent display tube having a G structure.

That is, the present invention is characterized in that the above-mentioned conventional fluorescent display tube of COG structure is provided with an external electrode for the purpose of aging as a separate terminal electrode. The separate electrode provided here is wire-connected as a branch of the wiring film 2, and has a structure that can be removed by cutting or the like after a high luminance level is obtained after aging. ing. In the structure according to the present invention, it is not affected by the withstand voltage of the LSI mounted on the board,
A sufficiently high voltage can be applied from a separate electrode, making it possible to provide a fluorescent display tube that can obtain a high brightness level.The present invention will now be described in detail with reference to the drawings.

That is, FIGS. 3 and 4 are a cutaway plan view and a cross-sectional view taken along the line B-B of an embodiment of a fluorescent display tube having a COG structure according to the present invention. In the figures, 1 is made of glass. This is the board. This board l
A plurality of wiring coatings 2 electrically connect adjacent common segment electrodes, an insulating coating 3 insulating between each wiring coating 2 and each segment electrode, and a plurality of wiring coatings 2 arranged in parallel on the upper surface. A plurality of segment electrodes 4 constituting each anode display section 6 and a phosphor layer 5 on the upper surface of each segment electrode 4 are deposited in a stacked manner to constitute an anode substrate IA. Further, each wiring film 2 electrically connects adjacent common segment electrodes 4 via connection holes 7 provided with an insulating film 31C. Furthermore, this wiring coating 2 branches into two, and on the substrate IB on which the one-piece LSI chip is mounted, an uninvented terminal serving as another electrode is provided in the opening 30 of the insulating coating 3. Each of the conductive surface portions 31 extends to the plurality of conductive surface portions 31 for connection to the lead-in wires 32 . In this figure, the same reference numerals are used for the same sections as in FIGS. 1 and 2, and their basic roles are the same as in the conventional method.

Moreover, each 41! connected to each segment electrode 4 via the wiring coating 2! A contact portion 34 is provided on the surface portion 31 via a spring portion 33 at a portion of the terminal lead-in wire 32 for a plurality of segment electrodes that hermetically penetrates the sealing portion 22 and extends inward from the sealing portion 22. are brought into contact with each other by the spring force and are electrically conductive.
The method for connecting the mold surface portions 31 is a well-known method for connecting a so-called frame type fluorescent display tube.

In this way, in a fluorescent display tube according to the present invention.

Each segment electrode 4 is provided with at least two
It has electrodes that can be electrically connected from several places. Here, the external terminal introduction line 32 is used as an external voltage application electrode when the phosphor is activated. By providing this electrode, there is no need to use the drive circuit section 14 formed on the substrate IE for aging, and it becomes possible to apply a high voltage that provides luminance equal to that of the fluorescent light. We are now able to provide display tubes.

In the fluorescent display tube according to the present invention as well, it is desirable that the drive circuit section 14 formed on the substrate IB be formed after an aging process using the external terminal lead-in wires 32. This was selected for its ease of handling and economy.
We select only fluorescent display tubes that are known to provide sufficiently high brightness.

This is because the driving LSI can be mounted on this.

Further, in the above-described uninvented embodiment, the terminal lead-in wire 32 for aging is drawn out in the direction 180 degrees opposite to the drive circuit section 14, but there is no restriction on the direction, for example, the drive circuit section 14. Of course, it is okay to be on the other side.

Furthermore, the wiring coating 2 is used instead of the terminal lead-in wire 32 that uses spring force as an electrode terminal for aging.

Needless to say, it may be used as it is by extending it into the air.

As described above, in the fluorescent display tube having the COG structure according to the present invention, it is possible to freely and sufficiently supply voltage from a separate electrode without being affected by the withstand voltage of the LSI to be mounted. A significant effect was confirmed in eliminating brightness defects caused by insufficient aging.

[Brief explanation of the drawing]

Fig. 1 and Fig. 2 are a cutaway plan view of essential parts showing an example of a multi-digit display tube having a conventional C0GQ structure, and A-
A cutaway sectional view of part A, FIGS. 3 and 4 show C according to the present invention.
FIG. 9 is a cutaway plan view of essential parts and a cutaway sectional view taken along line B-B, showing an embodiment of a multi-digit display tube having an OG structure. 1... Board, 2... Wiring coating, 3... Insulating coating,
4... Segment electrode, 5... Dielectric body layer, 6...
・Anode display section, 11... control electrode, 12... cathode,
13...Top plate. 14... Drive circuit section, 15... LSI chip, 17
... Pad portion, 19... Protective film, 20... External terminal, 31... Conductive surface portion, 32... Terminal lead-in wire, 33
...Spring part. 34...Contact part 10- h j Figure prize 2 Figure 1 Gl, 5 lol, 3 Mouth z 4 Figure

Claims (1)

[Scope of Claim] A fluorescent display tube having a structure in which a multi-digit display section having a phosphor layer and a drive circuit section for operating the display section are integrally formed on the same substrate. A fluorescent display tube comprising an electrode capable of driving a display section through at least one drive circuit and an electrode capable of directly driving the display section.