JPS6297231A - Aging voltage supplying method for fluorescent character display tube - Google Patents

Abstract

PURPOSE:To shorten the aging process time by applying voltage intermittently between a filament cathode and an anode or a grid electrode in synchronization with a pulse voltage to be applied onto the anode or the grid electrode. CONSTITUTION:A fluorescent character display tube 11 is formed with a fluorescent display section 13 comprising an anode electrode 14, a grid electrode 15 and a filament cathode 16 and an IC ship section 12 for driving the fluorescent display section 13. For the purpose of activation of fluorescent material or gas adsorption, the IC chip section 12 is driven by a pulse signal 26 to perform aging. Here, the pulse signal 26 is fed to a pulse modulator 29 to synchronize a power source 22 with the pulse signal 26, thus controlling the voltage to be applied onto the filament cathode 16 intermittently. Consequently, the current flowing during unlighted period is interrupted to enable application of a high voltage without burdening the IC chip section 12, resulting in shortening of the aging time.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention provides a fluorescent display having a structure in which a fluorescent display section and a semiconductor circuit section for driving the fluorescent display section are integrally molded on the same glass substrate. This invention relates to a tube aging voltage supply method.

INDUSTRIAL APPLICATION This invention is utilized for the aging treatment of a fluorescent display tube after manufacture or when it is incorporated into another device.

〔overview〕

The present invention provides a method for supplying an aging voltage to a fluorescent display tube, which is carried out before the start of use for activating the fluorescent substance or adsorbing gas, by applying a voltage to the filament cathode in synchronization with a pulse voltage applied to the anode electrode or the grid electrode. By intermittently applying an aging voltage between the anode electrode or the grid electrode, the aging process time is shortened and the influence on the semiconductor circuit elements of the fluorescent display tube is reduced.

[Conventional technology]

Conventionally, fluorescent display tubes in which a fluorescent display section and a semiconductor circuit section for driving it are formed on the same glass substrate usually have a "chip on glass" (hereinafter referred to as COG) structure. It is said to be a thing.

FIG. 3 is a partially cutaway perspective view of a fluorescent display tube having this COG structure.

Fluorescent display tubes having such a COG structure need to be aged before use in order to improve the brightness of the phosphor.

Generally, the activation and outgassing of the phosphor is performed by electron bombardment stimulation from a filament, but in order to increase the luminous efficiency, a voltage higher than the actual usage conditions of the phosphor display tube is applied to each electrode in a high-temperature atmosphere. do. In this case, an anode voltage and a grid voltage of 2 to 5 times the normal rating are applied, the temperature of both electrodes rises, and the released residual gas is absorbed by the getter to achieve a high degree of vacuum.

In order to carry out such aging, in a conventional fluorescent display tube having a COG structure, an aging voltage is supplied by a method according to a block diagram shown in FIG.

In FIG. 4, the fluorescent display tube 11 is schematically shown, and includes a fluorescent display section 13 composed of an anode electrode 3, a grid electrode 7, and a filament cathode 8,
A transistor 28 that constitutes a semiconductor circuit section that drives
, and an ICC shifter 112 consisting of resistors 23, 25, and the like.

In order to age the fluorescent display tube 11 configured in this way, an ICC shifter 112 is connected to the terminal 18 of the fluorescent display tube 11.
A voltage that becomes a pulse signal (SG) 26 for pulse driving is connected in consideration of the allowable power loss of
4 is connected, and an AC fin filament power source (Ef) 21 and a power source (Ecc) 22 for driving the filament are connected to the terminal 17.
Connect with.

Here, aging is the power supply (V cc) 24 or the power supply (
This can be done by adjusting the respective voltages vc (Ecc) 22 or ECC to increase the potential difference between the anode electrode 14 of the fluorescent display section 13 and the filament 16.

A characteristic diagram of the potential relationship between each electrode and terminal at this time is shown in FIG.

In FIG. 5, the pulse signal (SG) is in the form of rHJ and "L" pulses, and the ICC shift 112 causes a difference between VC and -VSS between the anode electrode 14 and the grid electrode 15 and the filament 16. Waveform a that switches
This shows that a voltage with a waveform is applied to the filament 16 from an AC power source (Ef) 21 for heating the filament 16.

As is clear from FIG. 5, this aging method uses the potential relationship between the power source (Vis) 27 and the power source (Ecc) 22 during the period when the pulse-driven fluorescent display tube should not be lit. A current flows through the anode electrode 14 and the grid electrode 15 of the fluorescent display tube. Therefore, a current flows through the pull-down resistor 25 of the ICC shifter 112, but considering the allowable current of the pull-down resistor 25, this current cannot be made very large.

That is, a sufficient voltage necessary for aging cannot be applied between the anode electrode 14 and the filament 16.

[Problem to be Solved by the Invention 3] As explained above, in a fluorescent display tube with a COG structure, it is not possible to apply the high voltage necessary for aging between the anode electrode and the filament, and therefore the aging time is prolonged. Furthermore, there are limitations on the type of IC chip that can be used, which poses problems in terms of productivity and economy.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a method for supplying an aging voltage to a fluorescent display tube, which improves these problems, shortens the aging time of the fluorescent display tube, and reduces the influence on semiconductor circuit elements.

[Means for solving problems]

The present invention provides a fluorescent display tube having a fluorescent display section including an anode electrode, a grid electrode, and a filament cathode, and a semiconductor circuit section for driving the fluorescent display section. The method of aging by applying a voltage is characterized in that an aging voltage is intermittently applied between the filament cathode and the anode electrode or the grid electrode in synchronization with the pulse voltage.

[Effect]

By pulse-driving the voltage of the DC bias power supply applied to the filament terminal in synchronization with the pulse signal input to the anode electrode and grid electrode of the fluorescent display tube, during the non-lighting period unnecessary for aging, Current flowing between the anode electrode and the grid electrode and the filament can be interrupted.

Therefore, by increasing the potential difference between the anode electrode and grid electrode and the filament necessary for aging,
Even if the aging effect is strengthened, the elements of the semiconductor circuit will not be affected.

〔Example〕

Hereinafter, one embodiment of the present invention will be described in detail using the drawings.

FIG. 3 is a partially cutaway perspective view of a fluorescent display tube having a COG structure. In this figure, an anode substrate 5 including a plurality of wiring films 2, a dot anode electrode 3, a drive circuit section (hereinafter referred to as a pad section) 4 laminated and deposited on a glass substrate l;
On this anode substrate 5, an external lead 6, a grid electrode 7, and a filament cathode 8, which are input terminals of the band portion 4, are provided. Furthermore, the pad part 4
An IC chip 9, which is a semiconductor circuit section, is mounted on the board by a bonding method or the like, and the entire wooden board is sealed with a light-transmitting cover glass 10.

This COG-structured fluorescent tube is driven via the IC chip 9 by applying current to the terminal of the external lead 6.

FIG. 1 shows a block diagram of an embodiment of the present invention.

The fluorescent display tube 11 shown by the dashed line in FIG. 1 is a schematic diagram of the circuit shown in the partially cutaway perspective view of the fluorescent display tube shown in FIG. The grid electrode 7, the filament cathode 8 and the IC chip 9 are
In the figure, an anode electrode 14, a grid electrode 15,
It is represented by a filament 16 and an IC chip portion 12. The fluorescent display section 13 and the IC chip section 12 shown in FIG. 1 are actually arranged on the surfaces of the anode substrate 5 and the pad section 40, respectively, as shown in FIG. 3.

In FIG. 1, a fluorescent display tube 11 has an anode electrode 14.
, a fluorescent display section 13 composed of a grid electrode 15 and a filament 16 driven by an AC power source (Ef) 21, and an IC chip section 1 that drives the fluorescent display section 13.
It consists of 2.

A power supply (V cc) 24 and a power supply (V 5s) 27 are connected to the IC chip section 12 from the outside of the fluorescent display tube 11, and a pulse signal (SG) is connected to the fluorescent display section 13.
26 is input, the anode electrode 14 and the grid electrode 15
and drive.

Here, the feature of the present invention is that the anode electrode 14
A power source (Ecc) 22 that sets the potential difference between the grid electrode 15 and the filament 16 is synchronized with the pulse voltage (SG) 26 by a pulse modulator 29, and a pulsed voltage is intermittently applied to the filament 16. It is about supplying.

Next, the operation of the present invention will be explained using a characteristic diagram of potential relationships shown in FIG.

Now, the pulse signal (SG) 26 is sent to terminal 1 of the fluorescent display tube 11.
8, the voltage value V is applied to the anode electrode 14 and the grid electrode 15 by the operation of the IC chip section 12.
A pulse voltage indicated by signal a that switches between CC and -VSS is applied in synchronization with pulse signal (SG) 26.

At the same time, the pulse signal (SG) 26 is also input to the pulse modulator 29, which switches the power supply Ecc, which sets the potential of the filament 16, so the potential of the filament 6 changes between ECC and ECC' in the pulsed manner indicated by the signal. The switching works.

The alternating current signal (E f
) 21 is an AC voltage power source for heating the filament.

Therefore, when the pulse signal (SG) 26 is rHJO, the potential difference between the anode electrode 14 and the grid electrode 15 and the filament 16 is r vCC + EccJ, and by setting a predetermined voltage ECC, a sufficient potential difference for aging can be provided. I can do it.

Furthermore, when the potential of the pulse signal (SG) 26 is rLJ, the filament potential is set to a voltage higher than the voltage rVcJ applied to the anode electrode 14 and the grid electrode 15 by the potential setting of the pulse modulator 29. It is possible to prevent current from flowing through the fluorescent display tube section. That is, no current flows from the IC chip section 12 during this period.

In this way, by synchronizing the pulse-driven fluorescent display tube with this pulse drive voltage and pulse-operating the DC bias voltage of the filament, the current flowing through the IC chip during the non-lighting period during pulse drive can be reduced. Since it can be cut, aging can be performed by applying a high voltage without putting a burden on the IC chip, and the aging time can be shortened.

〔Effect of the invention〕

As described above, according to the present invention, aging can be performed by applying a high voltage to the IC chip without placing an electrical burden on it, so the selection range of IC chips to be used is expanded and the variety of types of fluorescent display tubes is increased. Facilitates and economics of fluorescent display tubes,
This has the great effect of improving reliability and characteristics.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram of an embodiment of the present invention. FIG. 2 is a voltage-related characteristic diagram of the above embodiment. FIG. 3 is a partially cutaway perspective view of a fluorescent display tube with a COG structure. FIG. 4 is a block diagram of a conventional example. FIG. 5 is a voltage-related characteristic diagram of a conventional example. DESCRIPTION OF SYMBOLS 1... Glass substrate, 2... Wiring film, 3... Dot anode electrode, 4... Pad part, 5... Anode substrate, 6... External extraction lead, 7.15... - Grid electrode, 8... Filament cathode, 9... IC chip, IO... Cover glass, 11... Fluorescent display tube, 12... IC chip section, 13... Fluorescent display section ,1
4... Anode electrode, 16... Filament, 21
...Filament (E") power supply, 22...Power supply (E")
cc), 24'''Electric/JfJ, (Vcc), 27-
Power supply (Vss), 23.25...Resistor, 28...Transistor, 26...Pulse signal (SG), 29...
・Pulse Mod Lake. Redundancy 2 Figure outline oblique figure 3 Figure

Claims (1)

[Claims] (1) Applying a pulse voltage to the anode electrode or grid electrode of a fluorescent display tube equipped with a fluorescent display section including an anode electrode, a grid electrode, and a filament cathode, and a semiconductor circuit section that drives this fluorescent display section. Aging of a fluorescent display tube, characterized in that an aging voltage is intermittently applied between the filament cathode and the anode electrode or the grid electrode in synchronization with the pulse voltage. Voltage supply method.