JPH1185096A - Method of driving field emission display element - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method of driving a field emission display device which efficiently sends off positive gas ions generated in an envelope in a scanning direction and can induce them into a getter room. SOLUTION: A getter room 12 is arranged on one side of a cathode electrode C in the longitudinal direction. An electron discharge area S selected by a gate electrode G and a cathode electrode C discharges electrons e while the area is moving to a getter room 12, by scanning the gate electrode group G in the direction of the getter room 12 and applying a driving voltage to a part or whole of the cathode electrode group C. Positive ions I generated by collisions between the emission electrons e and the residual gas in the envelope 5 are successively induced into the electron discharge area which is moving in the scanning direction of the gate electrode group G and sent off to the getter room 12.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for driving a field emission display device.

[0002]

2. Description of the Related Art FIG. 11A shows a field emission display device (Fi
FIG. 2B is a perspective view of a field emission cathode, and FIG. 2C is a cross-sectional view of the field emission cathode.

As shown in FIG. 11A, a field emission display element 1 is provided between a front plate 2 and a rear plate 3 facing each other at a predetermined interval, and between outer peripheral portions of the front plate 2 and the rear plate 3. And an envelope 5 comprising the spacer member 4 provided.

As shown in FIG. 11 (b), an anode electrode A having a light-transmitting property is attached to the entire inner surface of a transparent front plate 2. A phosphor 6 is continuously adhered thereon with a predetermined thickness to form a solid light emitting portion 7. The potential V of the gate electrode G, which will be described later the potential V _A of the anode electrode A
_{If G is set} to be positive, that is, if a potential difference V _AG between the anode A and the gate electrode G is given so that V _A > V _G , the solid light emitting unit 7 can be used as a field emission cathode 8 described later. In response to the impact of the electrons emitted from each of the electron emission regions S, the light is emitted in a point-like manner. Usually, this potential difference V _AG is 100 to 400
About V. This dot-shaped light emitting portion is called a display unit.
By selecting the display unit of the light emitting unit, an arbitrary image or the like can be displayed on the light emitting unit.

On the inner surface of the back plate 3, a field emission cathode 8 is formed as an electron source. 11 (b) and 11 (c), the basic structure of the field emission cathode 8 will be described.
First, a cathode electrode C is formed on the inner surface of the back plate 3. An insulating layer 9 is formed on the cathode electrode C and the back plate 3. A gate electrode G is formed on the insulating layer 9. A hole 10 reaching the cathode electrode C is formed in the gate electrode G and the insulating layer 9 by etching. On the cathode electrode C in the hole 10, a cone-shaped emitter 11 is formed.

Next, the matrix structure of the field emission cathode 8 will be described. The gate electrodes G are band-shaped, and a large number of the gate electrodes G are arranged at predetermined intervals. The longitudinal direction of the gate is called the row direction. Further, the cathode electrode C is also band-shaped, and a large number of the cathode electrodes C are arranged at predetermined intervals. The longitudinal direction of the cathode electrode C is called a column direction. Accordingly, the field emission cathode 9 has a matrix structure of the gate electrode G and the cathode electrode C.

[0007] Then, as the potential V _G of the gate electrode G is positive with respect to the potential V _C of the cathode electrode C, that is, V
By scanning a row so that _G > V _C and applying a potential V _C as a driving voltage to a column, a potential difference V _GC between the scanned gate electrode G and the cathode electrode C to which the potential V _C is applied is applied.
, The intersection of the two can be selected as the electron-emitting portion. Usually, this potential difference V _GC is about 10 to 100V.

[0008] Similarly, as the potential V _G of the gate electrode G is positive with respect to the potential V _C of the cathode electrode C, that scans the column such that V _G> V _C, the line by applying a potential V _G as the driving voltage, be given a potential difference V _CG between the gate electrode G of applying a cathode electrode C and the potential V _G was scanned, it can be selected intersections of both the electron emission portion. Normally, this potential difference V _CG is about 10~100V.

The electron emission region at the intersection of the gate electrode G and the cathode electrode C is called an electron emission region S. The electron emission areas S are regularly arranged. Each electron emission region S faces the display unit of the light emitting unit 7, and by turning on / off each electron emission region S, lighting / non-lighting of the facing display unit of the light emitting unit 7 is selected. A desired image or the like can be displayed on the light emitting unit 7.

The envelope 5 is provided with a getter chamber 12 for keeping the interior of the envelope 5 in a high vacuum state. The getter chamber 12 communicates with one of the side walls of the envelope 5 or the back plate 3. Inside the getter chamber 12, there is provided a getter 13 in which a getter substance is filled in a ring-shaped container. In the getter room 12,
An exhaust pipe 14 is attached to suck the inside of the envelope 5. Getter 13 by high frequency induction heating from outside
Is heated and the getter material evaporates and the getter chamber 1
A getter mirror 15 is formed on the inner surface of the second.

The residual gas remaining in the envelope 5 floats in the envelope 5 and the getter chamber 12 communicating with the envelope 5 and is captured by the getter mirror 15.

[0012]

As described above, the potentials applied to the anode electrode A, the gate electrode G, and the cathode electrode C generally have the following relationship. From V _A> V _G> V _C This residual gas released from the fluorescent screen or the like is ionized between the anode A- gate electrode G, the direction of the cathode electrode C by a potential difference V _AG and V _GC described above proceed. The ions that have proceeded in the direction of the cathode electrode C are neutralized by electrons that have just been emitted from the emitter 11 and have not yet been sufficiently accelerated, and collide with and adhere to the emitter 11 in the vicinity of the emitter 11.

However, when the field emission display element 1 is driven, the electrons emitted from the electron emission region S collide with the residual gas in the envelope 5 and the generated positive gas ions adhere to the emitter 11. . Therefore, it is a well-known fact that the work function of the emitter 11 is increased, the emission efficiency of the emitter 11 is deteriorated, and its life is shortened.

On the other hand, the getter chamber 12 communicates with either one of the side walls of the envelope 5 or the back plate 3 as described above, but this arrangement position is different from the matrix structure of the gate electrode G and the cathode electrode C. It has nothing to do with it.

From the above facts, the inventor of the present application proposed that the life of the emitter 11 be extended and the gate electrode G and the cathode electrode C be extended.
Paying attention to the arrangement position of the getter chamber 12 in relation to the matrix structure of the above, and by arranging the getter chamber 12 in the scanning direction of the gate electrode G or the cathode electrode C, positive gas ions generated in the envelope 5 Of the field emission type display element 1 which can be efficiently sent out in the scanning direction and attracted to the getter chamber 12.

[0016]

Next, means for solving the above-mentioned problems will be described with reference to FIGS.
0 will be described.

According to the first aspect of the present invention, there is provided an electric field having a plurality of strip-shaped cathode electrode groups C provided with the emitters 11 and a plurality of strip-shaped gate electrode groups G orthogonal to the cathode electrodes C above the emitters 11. An emission cathode 8, a getter chamber 12 communicating with an envelope 5 surrounding the field emission cathode 8, and a getter mirror 15 for capturing residual gas generated in the enclosure 5 in the getter chamber 12. The field emission display element 1 having the above structure is driven from the electron emission region S by driving a plurality of electron emission regions S arranged in a matrix where each of the cathode electrodes C and each of the gate electrodes G intersect. In the method of driving the field emission display element 1 that emits electrons e, the getter chamber 12 is disposed in one longitudinal direction of the cathode C, and the gate electrode group G is connected to the getter. By scanning toward the cathode chamber 12 and applying a drive voltage D to part or all of the cathode electrode group C, the electron emission region S selected for the gate electrode G and the cathode electrode C is moved to the getter chamber 12. The electron e is emitted while moving toward the positive electrode, and positive gas ions I generated by the collision between the emitted electron e and the residual gas in the envelope 5 move toward the scanning direction of the gate electrode group G. The electron emission region S is sequentially attracted and sent to the getter chamber 12.

According to a second aspect of the present invention, there is provided an electric field having a plurality of strip-shaped cathode electrode groups C provided with the emitters 11 and a plurality of strip-shaped gate electrode groups G orthogonal to the cathode electrodes C above the emitters 11. An emission cathode 8, a getter chamber 12 communicating with an envelope 5 surrounding the field emission cathode 8, and a getter mirror 15 for capturing residual gas generated in the enclosure 5 in the getter chamber 12. The field emission display element 1 having the above structure is driven from the electron emission region S by driving a plurality of electron emission regions S arranged in a matrix where each of the cathode electrodes C and each of the gate electrodes G intersect. In the method of driving the field emission display element 1 for emitting electrons e, the getter chamber 12 is disposed in one of the longitudinal directions of the gate electrode G, and the cathode electrode group C is connected to the getter chamber. By scanning toward the gate chamber 12 and applying a drive voltage D to a part or the entirety of the gate electrode group G, the electron emission region S selected for the gate electrode G and the cathode electrode C is moved to the getter chamber 12. The positive gas ions I generated by the collision of the emitted electrons e with the residual gas in the envelope 5
Are sequentially attracted to the electron emission region S which moves in the scanning direction of the cathode electrode group C, and are sent to the getter chamber 12.

According to a third aspect of the present invention, in the method of driving the field emission display element 1 according to the first aspect, two adjacent gate electrodes G _i and G _{i + 1} are set to be smaller than the other gate electrodes G. Scanning is performed toward the getter chamber 12 with a potential difference provided.

According to a fourth aspect of the present invention, in the method of driving the field emission display device 1 according to the second aspect, the two adjacent cathode electrodes C _j and C _{j + 1} are set to have a potential difference higher than that of the other cathode electrodes. And scanning is performed toward the getter chamber.

According to a fifth aspect of the present invention, there is provided the electronic device of the first aspect.
In the method for driving the field emission display element 1, the scanning is performed.
Gate electrode G_iAt the same time, the scanning gate electrode G_i
Gate electrode G adjacent to the side opposite to the scanning direction of_i-1Before
The potential V of the other gate electrode G _G0Higher scanning gate
Gate electrode G_iPotential V_GThe emitter in a lower range than
Potential V at which no electron e is emitted from_G-Scan
The positive gas ion I is adjacent to the opposite side.
Gate electrode G_i-1It extrudes in the scanning direction from
It is a sign.

[0022] According to a sixth aspect of the invention, according to claim 2 driving method of a field emission type display device 1 according simultaneously with the cathode electrode C _i to the scanning, opposite to the scanning direction of the cathode electrode C _i to the scanning Cathode electrode C _i-1 adjacent to
In addition, scanning is performed by applying a potential V _C− that does not emit electrons from the emitter 11 in a range higher than the potential V _C0 of the other cathode electrode C and lower than the potential C _i−1 of the cathode electrode to be scanned. It is characterized in that the positive gas ions I are pushed out in the scanning direction from the cathode electrode Ci _-1 adjacent on the opposite side.

According to a seventh aspect of the present invention, in the method of driving the field emission display element 1 according to the first aspect, the scanning gate electrode G _{i is} simultaneously scanned with the scanning gate electrode Gi.
_By scanning the gate electrode G _{i + 1} adjacent to the scanning direction _i by applying a potential VG ₊ lower than the potential _VG0 of the other gate electrode G to scan the gate electrode G i with the positive gas ions I a gate electrode G adjacent in the scanning direction from _i
The feature is to attract to _{i + 1} .

According to an eighth aspect of the present invention, in the method of driving the field emission display device 1 according to any one of the first to seventh aspects, the getter mirror 12 is given a negative potential. And

[0025]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS First, a method for driving a field emission display device 1 according to a first embodiment of the present invention will be described with reference to FIGS. The same reference numerals as in FIG. 11 denote the same parts, and a description thereof will be omitted.

FIG. 1 is a diagram showing a matrix structure of a field emission cathode. The gate electrodes G are band-shaped, and m gate electrodes G are arranged at predetermined intervals. Further, the cathode electrodes C are also band-shaped, and n are arranged at predetermined intervals. Accordingly, the field emission cathode 8 has a matrix structure of the gate electrode G and the cathode electrode C.

[0027] As shown in FIG. 6, when the getter compartment 12 is provided in the longitudinal direction of the cathode electrode C is the gate electrodes G, sequentially gate electrode from the gate electrode G ₁ G _m
A convex pulse voltage P ₁ having a period T is given until the getter chamber 12 is scanned. The potential of the pulse voltage P ₁ is V _G
And Further, neighboring gate electrodes _{G i, G i + 1 (} i =
1, 2, 3,. . . . m-1, m) is the period T of the pulse voltage P ₁ between the pulse width t _p and a blanking time t
It is shifted by _b minutes.

When a drive voltage D is applied to part or all of the cathode electrode C at the same time as the gate scanning, the intersection between the two can be selected as the electron emission region _Sij . The potential of the drive voltage D is set to V _C. That is, a potential difference V _GC occurs between the scanned gate electrode G ₁ and the cathode C to which the potential V _C is applied. As a result, as shown in FIG. 2, first, electrons e are emitted from the emitter 11 of the electron emission region S _1j where the scanned gate electrode G ₁ and the cathode C to which the potential V _C is applied intersect. The emitted electrons e collide with the residual gas (H ₂ , H ₂ O, CO, N ₂ , CO _2, etc.) in the envelope 5, and the residual gas is ionized, and the positive gas ions I (H ₂ ⁺ , H
₂ O ⁺ , CO ⁺ , N ₂ ⁺ , CO ₂ ^+, etc.).

Further, since the gate electrode G is sequentially scanned, as shown in FIG. 3, the scanned gate electrode G ₂
The electron e is emitted from the emitter 11 in the electron emission region S _2j where the cathode C intersects with the potential V _C. In other words, the electron emission region S from which the electrons e are emitted moves toward the getter chamber 12. As a result, the previously generated positive gas ions I are attracted in the direction of the electron emission region S _2j moved by the gate scanning.

Next, when the gate electrode G ₃ is scanned, as shown in FIG. 4, electrons are emitted from the emitter 11 of the electron emission region S _3j where the gate electrode G ₃ and the cathode C to which the potential V _C is applied intersect. e is released. Thus, the previously generated positive gas ions I are attracted in the direction of the electron emission region S _3j moved by the gate scanning.

The attracted positive gas ions I are transferred to the emitter 11 in the new electron emission region S _{4j at the} destination.
Due to the collision of the electrons e emitted from the gate electrode G with the newly generated positive gas ions I, the electrons e are further drawn to the electron emission region S _4j moved in the scanning direction of the gate electrode G.

This gate scan is directed to the getter chamber to G ₁
At the same time repeated sequentially G _m to the period T from the mobile, to a part or the whole of the cathode electrode C by applying a driving voltage D of the potential V _C, the positive gas ions I in the scanning direction of stochastically gate electrode G Then, as shown in FIG. 5, the light is effectively sent into the getter chamber 12 and is attracted to the getter mirror 15.

Next, a second embodiment will be described with reference to FIGS.
This will be described with reference to FIG. In the first embodiment, the gate electrode G
The example has been described sequentially scanning by applying a pulse voltage P ₁ convex repeated in period T, in this embodiment, FIG. 8
As in, at the same time sequentially scans by applying a pulse voltage P ₁ convex repeated with a period T to the gate electrode G _i, sequential convex to the gate electrode G _i-1 which is adjacent to the side opposite to the scanning direction pulse voltage P Scan by giving ₂ .

In this case, the pulse voltage P_TwoIs given
Gate electrode G_i-1Potential V_G-Is the pulse voltage applied
Potential V of other gate electrodes that are not_G0Higher pulse power
Pressure P ₁Potential V_GLower range (V_G0<V_G-<V_G)
And the gate electrode G_i-1From the emitter 11 you want from
It shall be set to a level that does not emit electrons e.
You.

The operation of this embodiment is as follows.
First, as described above, the gate electrode G_iPulse voltage P
₁And scanning at the same time, the gate electrode G_i-1Potential
V_G-Pulse voltage P_TwoAnd scan. And Caso
The potential V is applied to part or all of the_CDrive voltage D
I can. Thereby, the pulse voltage P₁Is given
Gate electrode G_iAnd the cathode voltage to which the drive voltage D is applied.
Pole C_jPotential difference V _GCAnd the gate electrode G_iAnd Caso
Lead electrode C_jCrossing electron emission region S_ijFrom e
Is emitted and the positive gas ion
On-I occurs. By the way, the pulse voltage P_TwoGiven
Gate electrode G_i-1Is not scanned around
The potential is higher than the gate electrode G. Therefore, positive gas
I is the pulse voltage P_TwoGate electrode G provided with
_i-1Than the gate electrode G in the scanning direction _{i + 1}Effectively attract
Will be done. In other words, the positive gas ions I
Electrode G_i-1Will be boosted by

Next, a third embodiment will be described with reference to FIGS.
Explanation will be made using 0. In the first embodiment, the gate electrode
A convex pulse voltage P that repeats at a period T in G₁Give the order
Although the example of performing the next scan has been described, in the present embodiment, FIG.
As shown in FIG._iRepeats at cycle T
Convex pulse voltage P₁And scan sequentially,
Gate electrode G adjacent in the scanning direction_{i + 1}To successively concave pal
Voltage P_ThreeAnd scan sequentially. Pulse voltage P_ThreeIs
The potential V of the gate electrode G that has not been scanned around _G0than
It is set low.

At this time, part or all of the cathode electrode C
Potential V_CIs applied, the pulse voltage P₁But
The given gate electrode G_iAnd the drive voltage D
Cathode electrode C_jPotential difference V_GCThe game
Electrode G_iAnd cathode electrode C _jCrossing electron emission region
S_ijEmits electrons e. Then, the emitted electrons e and the remaining
Positive gas ions I are generated by the collision of the residual gas. Place
And the pulse voltage P_ThreeGate electrode G provided with_{i + 1}
Potential V_{G +}Of the gate electrode G that is not scanned around
Potential V_G0Lower. Therefore, the positive gas ions I
Voltage P_ThreeGate electrode G provided with_{i + 1}Direction,
That is, it is effectively induced in the gate scanning direction.
You.

In the first to third embodiments described above, the getter chamber 12 is provided in the longitudinal direction of the cathode electrode C, and the gate electrode G is scanned toward the getter chamber 12. Provided in the longitudinal direction of G,
The cathode electrode C may be scanned toward the getter chamber 12.

In any of the embodiments, if the negative potential V _{GB is applied} to the getter mirror 16, the positive gas ions I attracted to the vicinity of the getter chamber 12 can be more effectively reduced. 12 can be sent.

[0040]

As described above, in the method of driving a field emission display according to the present invention, positive gas ions generated in the envelope can be effectively attracted to the getter chamber, and can be reliably captured by the getter mirror. And the inside of the envelope can be made a high vacuum atmosphere.

Further, since the positive gas ions are attracted to the getter chamber, the ratio of the positive gas ions adsorbed on the emitter cone is reduced, and the life characteristics of the field emission display device can be improved.

[Brief description of the drawings]

FIG. 1 is a diagram showing a matrix configuration of a field emission cathode.

FIG. 2 is a cross-sectional view illustrating a driving state of the field emission display device according to the present invention.

FIG. 3 is a sectional view showing a driving state of the field emission display device according to the first embodiment of the present invention.

FIG. 4 is a sectional view showing a driving state of the field emission display device according to the first embodiment of the present invention.

FIG. 5 is a sectional view showing a driving state of the field emission display device according to the first embodiment of the present invention.

FIG. 6 is a timing chart showing a scanning state of the field emission display device according to the first embodiment of the present invention.

FIG. 7 is a sectional view showing a driving state of a field emission display device according to a second embodiment of the present invention.

FIG. 8 is a timing chart showing a scanning state of the field emission display device according to the second embodiment of the present invention.

FIG. 9 is a sectional view showing a driving state of a field emission display device according to a third embodiment of the present invention.

FIG. 10 is a timing chart showing a scanning state of the field emission display device according to the third embodiment of the present invention.

FIG. 11A is a cross-sectional view of a field emission fluorescent display device. (B) It is a perspective view of a field emission type cathode. (C) It is sectional drawing of a field emission type cathode.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Field emission type display element 5 ... Enclosure 8 ... Field emission type cathode 11 ... Emitter 12 ... Getter chamber 15 ... Getter mirror e ... Electron S ... Electron emission area C ... Cathode electrode G ... Gate electrode I ... Positive gas ion D: Drive voltage

 ──────────────────────────────────────────────────続 き Continued on front page (72) Inventor Shigeo Ito 629 Oshiba, Mobara-shi, Chiba Futaba Electronics Corporation

Claims (8)

[Claims] 1. A field emission cathode having a plurality of strip-shaped cathode electrode groups provided with an emitter, a plurality of strip-shaped gate electrode groups orthogonal to the cathode electrode above the emitter, and the field emission cathode. A field emission display device having a getter chamber communicating with the surrounding envelope and a getter mirror capturing the residual gas generated in the envelope in the getter chamber, wherein each of the cathode electrodes and each of the gate electrodes are A method of driving a field emission display element in which a plurality of electron emission regions arranged in a matrix that intersect is driven in a matrix to emit electrons from the electron emission regions, wherein the getter chamber is disposed in a longitudinal direction of the cathode electrode. And scanning the gate electrode group toward the getter chamber, and applying a drive voltage to a part or all of the cathode electrode group. As a result, the electron emission region selected for the gate electrode and the cathode electrode emits electrons while moving toward the getter chamber, and the electron emission region generated by the collision of the emitted electrons with the residual gas in the envelope. A method of driving a field emission display device, wherein gas ions are sequentially attracted to an electron emission region moving in a scanning direction of the gate electrode group and are sent to the getter chamber. 2. A field emission cathode having a plurality of strip-shaped cathode electrode groups provided with emitters, a plurality of strip-shaped gate electrode groups orthogonal to the cathode electrode above the emitter, and the field emission cathode. A field emission display device having a getter chamber communicating with the surrounding envelope and a getter mirror capturing the residual gas generated in the envelope in the getter chamber, wherein each of the cathode electrodes and each of the gate electrodes are In a method of driving a field emission display element in which a plurality of electron emission regions arranged in a crossing matrix are driven in a matrix to emit electrons from the electron emission regions, the getter chamber is disposed in a longitudinal direction of the gate electrode. And scanning the cathode electrode group toward the getter chamber, and applying a drive voltage to part or all of the gate electrode group. Accordingly, the electron emission region selected for the gate electrode and the cathode electrode emits electrons while moving toward the getter chamber, and a positive electrode generated by collision between the emitted electrons and a residual gas in the envelope. A method of driving a field emission display device, wherein gas ions are sequentially attracted to an electron emission region moving in a scanning direction of the cathode electrode group and are sent to the getter chamber. 3. The method of driving a field emission display device according to claim 1, wherein two adjacent gate electrodes are scanned toward the getter chamber with a potential difference greater than the other gate electrodes. 4. The method of driving a field emission display device according to claim 2, wherein two adjacent cathode electrodes are scanned toward the getter chamber with a potential difference being set higher than the other cathode electrodes. 5. A potential higher than the potential of the other gate electrode and lower than the potential of the gate electrode to be scanned, at the same time as the gate electrode to be scanned, to a gate electrode adjacent to the scanning gate electrode on the side opposite to the scanning direction. 2. The method of driving a field emission display device according to claim 1, wherein the positive gas ions are pushed out from the gate electrode adjacent to the opposite side in a scanning direction by applying a potential that does not cause electrons to be emitted from the emitter in a range. 6. A potential higher than the potential of the other cathode electrode and lower than the potential of the cathode electrode to be scanned is simultaneously applied to the cathode electrode to be scanned and to a cathode electrode adjacent to a side opposite to the scanning direction of the cathode electrode to be scanned. 2. The method of driving a field emission display device according to claim 1, wherein the positive gas ions are pushed out from a cathode electrode adjacent to the opposite side in a scanning direction by applying a potential at which electrons are not emitted from the emitter in a range. 7. The method according to claim 7, wherein the scanning is performed by applying a lower potential than a potential of the other gate electrode to a gate electrode adjacent to the scanning gate electrode in a scanning direction at the same time as the scanning gate electrode. 2. The method of driving a field emission display device according to claim 1, wherein the voltage is induced from the scanning gate electrode to a gate electrode adjacent in the scanning direction. 8. The method according to claim 1, wherein the getter mirror is supplied with a negative potential.