JP3223642B2 - Graphic fluorescent display tube - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a graphic fluorescent display tube having a field emission type electron source capable of graphic display of characters, figures, and the like, and more particularly to the diffusion of electrons emitted from a field emission type electron source. Related to suppressed graphic fluorescent display tubes.

[0002]

FIG. 6 shows an example of a conventional graphic fluorescent display tube having a field emission type electron source 120. As shown in FIG.
Anode substrate 100 and cathode substrate 1 facing each other at a predetermined interval
A side surface portion (not shown) is provided on the outer periphery of 01, and an envelope 102 whose inside is kept in a high vacuum state is configured.

[0003] A translucent striped anode conductor 103 is provided on the inner surface of the anode substrate 100. Anode conductor 1
03 is referred to as a vertical direction. This anode conductor 103
A plurality of dot-shaped phosphor layers 104 are attached at a predetermined interval on the substrate, and a display unit 105 is formed.

A field emission electron source 120 having a conical emitter electrode 106 is provided on the inner surface of the cathode substrate 101 facing the display section 105 of the anode substrate 100. First, a stripe-shaped cathode conductor 107 is provided on the inner surface of the cathode substrate 101 along a horizontal direction orthogonal to the anode conductor 103, and an insulating layer 109 having an opening 108 is provided on the cathode conductor 107. Have been. An emitter electrode 106 which is a conical electron emission portion is provided on the cathode conductor 107 in the opening 108. Further, on the upper surface of the insulating layer 109, the opening 10
8, and a stripe-shaped gate electrode 111 is provided along a direction perpendicular to the cathode conductor 107 (that is, a vertical direction parallel to the anode conductor 103).

As described above, since the cathode conductor 107 and the gate electrode 111 form a matrix, the display unit 105
By applying a predetermined anode voltage to the cathode electrode 107 and driving the cathode conductor 107 and the gate electrode 111 at an appropriate timing, the emitter electrode 106 that emits electrons can be selected, and the phosphor layer 104 of the display unit 105 facing the terminal can be selected. A desired light-emitting display can be obtained by light emission.

[0006]

According to the above-mentioned conventional graphic fluorescent display tube, the electrons emitted from the field emission electron source 120 spread and reach the display unit 105, so that the phosphor layer to be selected is selected. There is a problem in that another phosphor layer 104 adjacent to 104 leaks and emits light.

The inventors of the present application have made intensive efforts to solve the above-mentioned problems, and as a result, have made an invention useful for improving the above-mentioned problems. That is, in the present invention, a strip-shaped control electrode parallel to the gate electrode 111 is provided between the stripe-shaped gate electrodes 111 having a vertical direction as a longitudinal direction, and a negative potential is applied to the control electrode.

According to the above-mentioned invention, the diffusion of electrons in the horizontal direction perpendicular to the sheet of FIG. 6 is prevented, but in the vertical direction which is the longitudinal direction of the anode conductor 103 and the gate electrode 111, the electrons in FIG. As can be seen from the orbit, the electrons were widely diffused. For this reason, there is a problem that the vertically adjacent phosphor layer 104 that does not want to emit light leaks and emits light.

The present invention relates to a graphic fluorescent display tube comprising a field emission cathode in which a cathode conductor and a gate electrode form a matrix, and a display section in which a dot-shaped phosphor layer is provided on an anode conductor parallel to the gate electrode. In particular, it is an object of the present invention to prevent diffusion of electrons in the longitudinal direction of the anode conductor and prevent leakage light emission of the phosphor layer in the same direction.

[0010]

According to the first aspect of the present invention, there is provided a graphic fluorescent display tube according to the present invention, wherein a stripe-shaped cathode conductor, an emitter provided on the cathode conductor, and an insulating layer are provided on the cathode conductor. A field emission electron source having a stripe-shaped gate electrode provided in a direction intersecting with the cathode conductor, and a stripe-shaped anode conductor provided to face the field emission electron source and parallel to the gate electrode. In a graphic fluorescent display tube provided with a display unit having a plurality of dot-shaped phosphor layers provided at intervals on the anode conductor, the periphery of the phosphor layer is filled with an insulating layer.
A black insulating layer is provided between the phosphor layers .

[0011]

[0012]

Since electrons are charged in the insulating layer to form a negative electric field in the periphery, the electrons directed to the dot-shaped phosphor layers are converged in the longitudinal direction of the anode conductor or the gate electrode, and light is emitted. It hits only the phosphor layer.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A graphic fluorescent display tube 20 according to a first embodiment of the present invention will be described with reference to FIGS. Side surfaces (not shown) are provided on the outer periphery of the anode substrate 2 and the cathode substrate 3 which face each other at a predetermined interval, and an envelope 4 whose inside is maintained in a high vacuum state is configured.

On the inner surface of the anode substrate 2, a translucent striped anode conductor 5 made of an ITO film or the like is formed along the vertical direction. On the inner surface of the anode conductor 5, a dot-shaped phosphor layer 6 of a desired emission color is disposed at a predetermined interval, and a display unit 7 is formed. Further, a black insulating layer 30 having a light-shielding property is provided between the phosphor layers 6 and 6 arranged in the vertical direction, as shown in FIGS.

On the other hand, on the inner surface of the cathode substrate 3, stripes are provided for each horizontal row of the phosphor layer 6 along a direction (horizontal direction) orthogonal to the longitudinal direction (vertical direction) of the anode conductor 5. A cathode conductor 9 is formed. The cathode conductor 9
On top of this, an insulating layer 11 having an opening 10 is provided. A conical emitter 12 is provided on the cathode conductor 9 in the opening 10.

Further, on the upper surface of the insulating layer 11, a striped gate electrode 14 having a hole 13 corresponding to the opening 10 is provided with its longitudinal direction being parallel to the vertical direction. Each gate electrode 14 corresponds to a column of the phosphor layers 6 arranged in the vertical direction.

According to the above-described configuration, when the graphic fluorescent display tube 20 is driven, electrons are charged in the insulating layer 30, and the orbits of the peripheral electrons converge due to the negative electric field caused by the charged electrons.

For this reason, as shown in FIG. 1, electrons emitted from the electron emission portion 40 corresponding to one pixel of the field emission electron source by the synchronous driving of the cathode conductor 9 and the gate electrode 14 constituting the matrix are: The light is converged in the vertical direction and collides with only the desired phosphor layer 6, so that the adjacent phosphor layers 6 and 6 do not emit light.

As can be seen from FIG. 2, the distance between the phosphor layers 6 and 6 in this embodiment is larger in the vertical direction than in the horizontal direction. Since the insulating layer 30 is provided on each of the wide portions and the negative electric field generated by the charged electrons is used, the convergence of the electrons in the vertical direction is assured.

Further, if an insulating layer is provided between the phosphor layers 6 and 6 in the horizontal direction in FIG. 2 and the periphery of each phosphor layer 6 is filled with the insulating layer, electrons converge in all directions. Thus, electrons can be made to strike only the target phosphor layer 6.

The graphic fluorescent display tube 20a of the second embodiment will be described with reference to FIG. The same components as those in the first embodiment are denoted by the same reference numerals as those in FIG.

In this embodiment, an insulating layer 31 is provided on the gate electrode 14 facing the anode conductor 5 with the electron emission portion 40 corresponding to one pixel interposed therebetween. That is, the electrons spreading in the vertical direction on the electron emission side can be restricted, and the distribution width of the electrons reaching the corresponding phosphor layer 6 can be sufficiently suppressed. This makes it possible to completely prevent leakage of light from the adjacent phosphor layers 6 and 6 in the vertical direction as shown in FIG.

FIG. 4 shows a graphic fluorescent display tube 20b according to the third embodiment, which is provided with the insulating layers 30 and 31 of both embodiments. In this way, the above-described prevention of leakage light emission is more effective. The same components as those in the above-described embodiments are denoted by the same reference numerals as in FIGS.

FIG. 5 shows a graphic fluorescent display tube according to a fourth embodiment, in which a conductive layer 32 is provided on an insulating layer 30 in the first embodiment. If a negative potential of, for example, −200 V to −400 V is applied to the conductive layer 32,
The convergence of the electrons in the vertical direction due to the negative electric field is further ensured. The same components as those in the above-described embodiments are denoted by the same reference numerals as those in FIG.

In addition to the embodiments described above, according to the present invention, between the phosphor layers 6 and 6 and between the emission portions of the gate electrode 14, only the insulating layer having the conductive layer or only the insulating layer is provided. Can be provided in any combination.

[0026]

According to the present invention, in a graphic fluorescent display tube having a field emission electron source, each electron emission portion of a dot-like phosphor layer arranged on an anode conductor or of a gate electrode parallel to the anode conductor. Since the insulating layer is provided between them, the following effects can be obtained.

Since the electrons can be surely converged in the longitudinal direction of the anode conductor or the gate electrode by the negative electric field of the electrons charged in the insulating layer, leakage light emission in the same direction can be surely prevented.

Due to the convergence of the electrons, the ratio of the reactive current that does not contribute to light emission is reduced from 20 to 30% of the conventional case to 5 to 1%.
It can be greatly reduced to 5%.

If the insulating layer provided on the display section side is black, a black matrix surrounding each dot-shaped phosphor layer is formed, and the contrast of light-emitting display is improved.

[0030] The insulating layer provided over the gate electrode serves as a protective film for the gate electrode.

[Brief description of the drawings]

FIG. 1 is a view simultaneously showing a cross section of a graphic fluorescent display tube according to a first embodiment of the present invention and a trajectory of electrons during operation in the display tube.

FIG. 2 is a diagram showing a display unit of the graphic fluorescent display tube according to the first embodiment of the present invention.

FIG. 3 is a view simultaneously showing a cross section of a graphic fluorescent display tube according to a second embodiment of the present invention and a trajectory of electrons during operation in the display tube.

FIG. 4 is a view simultaneously showing a cross section of a graphic fluorescent display tube according to a third embodiment of the present invention and a trajectory of electrons during operation in the display tube.

FIG. 5 is a view simultaneously showing a cross section of a graphic fluorescent display tube according to a fourth embodiment of the present invention and a trajectory of electrons during operation in the display tube.

FIG. 6 is a view simultaneously showing a cross section of a conventional graphic fluorescent display tube and a trajectory of electrons during operation in the display tube.

[Explanation of symbols]

Reference Signs List 5 anode conductor 6 phosphor layer 7 display section 9 cathode conductor 11 insulating layer (of field emission electron source) 12 emitter 14 gate electrode 20, 20a, 20b, 20c graphic fluorescent display tube 30, 31 insulating layer 32 conductive layer

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A 3-52944 (JP, U) JP-A 2-69457 (JP, U) International Publication 92/9095 (WO, A1) (58) Fields surveyed (Int.Cl. ⁷ , DB name) H01J 31/12

Claims (1)

(57) [Claims] A striped cathode conductor; an emitter provided on the cathode conductor; and a striped gate electrode provided on the cathode conductor in a direction intersecting the cathode conductor via an insulating layer. A field emission electron source, a stripe-shaped anode conductor provided to face the field emission electron source and parallel to the gate electrode, and a plurality of dot-shaped phosphors provided at intervals on the anode conductor A graphic phosphor display tube provided with a display section having a layer, wherein a black insulating layer is provided between the phosphor layer and the phosphor layer so as to fill the periphery of the phosphor layer with an insulating layer. Graphic fluorescent display tube.