JP2006107924A - Display - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a display for enhancing display luminance and the degree of a vacuum. <P>SOLUTION: A black matrix layer 11, a number of phosphor layers R, G and B, and a getter layer 20 are film-formed on the inner surface of the front substrate of the display. The getter layer 20 is provided only at a region that does not overlap with the phosphor layers R, G, B and a region having a relative wide line space in a number of phosphor layers R, G and B in a matrix. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a display device that displays an image by emitting electrons from an electron-emitting device provided on a back substrate and exciting and emitting a phosphor layer provided on the front substrate.

  In recent years, field emission displays (FEDs), display devices (SEDs) equipped with surface-conduction electron-emitting devices, and the like are known as display devices having a flat envelope having a flat panel structure.

  In an FED or SED, a vacuum envelope in which a front substrate and a rear substrate arranged to face each other with a predetermined interval through a spacer are joined to each other through a rectangular frame side wall, and the inside is evacuated. Is configured.

  A phosphor layer of three colors and a metal back layer covering the phosphor layer are formed on the inner surface of the front substrate, and a large number corresponding to each pixel of the phosphor layer as an electron emission source for exciting and emitting the phosphor layer on the inner surface of the rear substrate. The electron-emitting devices are arranged.

  The phosphor layer is applied with a high voltage of several kV to the electron-emitting device, and the electron beams emitted from the individual electron-emitting devices are irradiated and accelerated by the electric field toward the corresponding phosphor layer. The phosphor layer is excited and emitted to display a color image.

  In this FED and SED, it is important to reduce the internal pressure because the atmosphere of the vacuum envelope causes the electron-emitting device and the phosphor layer to deteriorate. Conventionally, a member having an exhaust function is attached to a part of the panel. In this case, since the gap between the substrates of the vacuum envelope is a slight gap, the conductance is small and far from the exhaust member. It was insufficient to improve the atmosphere at the place.

  On the other hand, a method of forming a barium getter over the entire area of the front substrate on the phosphor layer at the same time as performing panel sealing in a vacuum chamber has been proposed (see, for example, Patent Document 1). According to this method, the vacuum atmosphere can be improved over the entire panel as compared with the case where the exhaust member is locally attached as described above.

However, in this case, since the getter is formed over the entire front substrate including the region overlapping with the phosphor layer, an extra energy loss occurs when the electron beam emitted from the electron-emitting device penetrates the getter layer. It was a factor that deteriorated brightness. In other words, the thickness of the getter layer is limited to a range where luminance degradation does not become a problem.
Japanese Patent Application No. 11-94340

  The present invention has been made in view of the above points, and an object of the present invention is to provide a display device that can increase display brightness and vacuum.

  In order to achieve the above object, a display device of the present invention has a vacuum envelope in which a front substrate and a rear substrate are opposed to each other, and a getter layer is provided at a place other than the phosphor light emitting portion of the front substrate. It is characterized by that.

  The display device of the present invention comprises a front substrate having a large number of phosphor pixels on the inner surface, and a vacuum envelope formed by sealing the peripheral edge of the front substrate, and the phosphor is disposed on the inner surface. A back substrate having a number of electron-emitting devices corresponding to the pixels, and a getter layer provided on the inner surface of the front substrate so as not to overlap the phosphor pixels.

  According to the above invention, since the electron beam for emitting the phosphor does not pass through the getter layer, energy loss can be reduced and display luminance can be increased.

  Further, the display device according to the present invention comprises a front substrate having a large number of phosphor pixels on the inner surface, and a peripheral portion sealed to the front substrate to constitute a vacuum envelope, and the phosphor on the inner surface. A back substrate having a number of electron-emitting devices corresponding to the pixels, and a getter layer provided on the inner surface of the front substrate at a position deviated from the trajectory of the electron beam emitted from the electron-emitting device.

  According to the above invention, since the electron beam emitted from the electron-emitting device does not interfere with the getter layer before reaching the phosphor pixel, energy loss due to passage through the getter layer can be eliminated, and display luminance can be increased.

  Since the display device of the present invention has the configuration and operation as described above, the display luminance can be increased and the degree of vacuum can be increased.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. First, an SED will be described as an example of a display device according to an embodiment of the present invention.
As shown in FIGS. 1 to 3, the SED includes a front substrate 2 and a rear substrate 4 made of glass plates each having a rectangular shape of 1 to 2 [mm], and these substrates 2 and 4 are spacers. 8 are arranged to face each other with a gap of about 1.0 to 2.0 [mm]. The front substrate 2 and the back substrate 4 are joined together via a rectangular frame-shaped side wall 6 to constitute a vacuum envelope 10 whose inside is a vacuum.

  A phosphor screen 12 for displaying an image is formed on the inner surface of the front substrate 2. This phosphor screen 12 is configured such that red, blue, and green phosphor layers R, G, and B and a black matrix layer 11 are arranged and the phosphor layer is covered with a metal back 14. The phosphor layers R, G, and B are formed in stripes or dots, and the metal back 14 is formed of a metal thin film such as aluminum.

  On the inner surface of the back substrate 4, a number of surface conduction electron-emitting devices 16 that emit an electron beam for exciting and emitting the phosphor layers R, G, and B are provided. These electron-emitting devices 16 are arranged in a plurality of columns and rows corresponding to each pixel, and each electron-emitting device 16 includes an electron-emitting unit (not shown) and a pair of device electrodes for applying a voltage to the electron-emitting unit. Has been. Further, on the inner surface of the back substrate 4, a large number of wirings 18 for applying a driving voltage to the respective electron-emitting devices 16 are provided in a matrix shape, and end portions thereof are drawn out of the vacuum envelope 10. Yes.

  In the SED, when an image is displayed, a voltage is applied between the element electrodes of the electron-emitting device 16 via the wiring 18 to emit an electron beam from an electron-emitting portion of the arbitrary electron-emitting device 16 and the phosphor screen 12. An anode voltage is applied to. Then, the electron beam is accelerated by the anode voltage and irradiated on the phosphor screen 12, and the desired phosphor layers R, G, and B are excited and emitted to display an image. At this time, the electron beam passes through the metal back 14 formed over the phosphor layers R, G, and B, and is irradiated to the phosphor layer.

  By the way, the front substrate 2 and the rear substrate 4 are sealed after degassing and firing in a vacuum atmosphere to form a vacuum envelope 10. Conventionally, the entire inner surface of the front substrate 2 is sealed in a vacuum atmosphere prior to sealing. A getter film was formed on the substrate to maintain a high vacuum after the panel was formed. Conventionally, the getter layer is formed in the entire area of the front substrate 2 with a film thickness of Ba or Ti of about 10 [nm] to 100 [nm]. From the viewpoint of luminance degradation, the getter layer is made thicker than 100 [nm]. Was not preferred.

  That is, when the getter layer is formed over the entire area of the front substrate 2, the getter layer is formed so as to overlap the phosphor layers R, G, and B, so that the electron beam also passes through the getter layer and reaches the phosphor layer. For this reason, the energy loss of the electron beam is large, and a sufficiently satisfactory display luminance cannot be obtained. In other words, when the film thickness of the getter layer is large, the energy loss of the electron beam is correspondingly increased, resulting in deterioration of luminance. Therefore, the film thickness of the getter layer is also limited.

  In addition, regarding the formation of the metal back 14, it is desirable to perform split formation as disclosed in JP-A-10-326583 and JP-A-2000-251797 from the viewpoint of suppressing the discharge current. In this case, when the getter film is formed over the entire area of the front substrate 2 as in the conventional case, the divided metal back is electrically conducted. Therefore, the getter layer is also disclosed in, for example, Japanese Patent Application Laid-Open No. 2003-068237, as with the metal back 14. It is desirable to form the electrodes electrically by the method shown.

FIG. 4 is an enlarged view of a main part for explaining the getter structure according to the first embodiment of the present invention.
As described above, the black matrix layer 11 and a large number of phosphor layers R, G, and B (phosphor pixels) are formed on the inner surface of the front substrate 2. The phosphor layers R, G, and B are alternately arranged in the arrow Y direction (horizontal direction in the figure) and arranged through a relatively narrow gap, and with respect to the arrow X direction (vertical direction in the figure). The pixel interval is relatively large. That is, the row spacing of the phosphor layers R, G, B is wider than the column spacing.

  In the present embodiment, the Ba getter 20 is formed with a thickness of 100 [nm] only on a relatively wide space between the phosphor layers R, G, B of the front substrate 2 through a mask (not shown). I made it. In other words, in the present embodiment, the getter on the inner surface of the front substrate 2 is located at a position where the electron beam emitted from the electron-emitting device 16 does not interfere, specifically at a position where it does not overlap the phosphor layers R, G, B. A layer was formed.

  By adopting the getter structure of the present embodiment, the energy loss of the electron beam can be suppressed lower than in the case where the getter layer is formed over the phosphor layers R, G, and B as in the prior art. It was possible to improve the display brightness by about 20 [%]. In addition, since the getter layer 20 is formed in the vicinity of the phosphor layers R, G, and B over the entire inner surface of the front substrate 2, the vacuum atmosphere can obtain the same characteristics as the conventional one over the entire display panel 10. did it. Furthermore, according to the present embodiment, since the electron beam emitted from the electron-emitting device 16 does not pass through the getter layer 20, the film thickness of the getter layer 20 does not adversely affect the display luminance, and the getter layer Can be made thicker than before, and a film thickness of 100 [nm] or more is also possible.

  Here, the case where the getter layer is a Ba getter has been described, but the getter layer may be a material having an exhaust capability, and may be Ti, Ta, or other materials, for example. Further, the film formation structure on the inner surface of the front substrate 2 is not limited to the above-described embodiment, and the arrangement of the phosphor layers R, G, and B can be arbitrarily changed, and other structures can be formed on the inner surface of the front substrate 2. May be added.

  Further, the surface area of the getter layer 20 may be increased by making the base of the getter layer 20 (the black matrix layer 11 in this embodiment) uneven. Thereby, the exhaust capacity per unit film-forming area of the getter layer 20 can be increased, and the degree of vacuum of the vacuum envelope 10 can be further increased.

FIG. 5 shows a getter structure according to a second embodiment of the present invention.
In the present embodiment, the getter layer 30 is formed in all regions that do not overlap the phosphor layers R, G, and B. In other words, the getter layer 30 is formed in substantially the same pattern as the black matrix layer 11. The getter layer 30 was printed by patterning with a printing plate on the black matrix layer 11, and the getter layer 30 formed later was activated to have an exhaust capability. Note that the getter material is Ti particles, which are activated as a getter by firing in a high-temperature reducing atmosphere after pattern formation and then firing in a vacuum.

  In the present embodiment, compared with the first embodiment described above, a mask vapor deposition apparatus is unnecessary, so that the manufacturing cost of the panel can be reduced.

FIG. 6 shows a getter structure according to a third embodiment of the present invention.
Here, in order to suppress a current during discharge, the getter layer 40 is divided in a two-dimensional direction together with a metal back (not shown). The getter layer 40 is electrically separated so as not to electrically conduct an electrically separated metal back region (not shown). The getter layer 40 is formed by the same printing process as that of the second embodiment.

  When forming such a divided pattern, for example, as shown in FIG. 7, a wall or enclosure 50 is formed in advance according to the pattern for forming the getter layer 40. Thereby, the protrusion of the getter layer 40 to the phosphor layers R, G, B and the like can be suppressed.

  In any case, in the present invention, the electron beam emitted from the electron-emitting device 16 is applied to the phosphor layers R, G, and B without interfering with the getter layers 20, 30, and 40, and energy loss is kept low. Can do. Thereby, after raising the vacuum degree of the vacuum envelope 10 to the desired value, display luminance can be raised.

  Note that the present invention is not limited to the above-described embodiment as it is, and can be embodied by modifying the constituent elements without departing from the scope of the invention in the implementation stage. Various inventions can be formed by appropriately combining a plurality of constituent elements disclosed in the above-described embodiments. For example, you may delete some components from all the components shown by embodiment mentioned above. Furthermore, you may combine the component covering different embodiment suitably.

  For example, in the above-described embodiment, the case where the getter layer is formed at a position that does not overlap the phosphor layers R, G, and B has been described. However, the present invention is not limited to this, and the getter layer is at least at a position deviated from the orbit of the electron beam. Should be formed.

1 is an external perspective view showing a vacuum envelope of an SED according to an embodiment of the present invention. FIG. 2 is a cross-sectional perspective view of the vacuum envelope of FIG. 1 cut along line II-II. The partial expanded sectional view which expands and shows the cross section of FIG. 2 partially. The principal part fragmentary enlarged view for demonstrating the getter structure which concerns on 1st Embodiment of this invention. The principal part fragmentary enlarged view for demonstrating the getter structure which concerns on 2nd Embodiment of this invention. The principal part fragmentary enlarged view for demonstrating the getter structure which concerns on 3rd Embodiment of this invention. The figure which shows the wall for forming the getter structure of FIG.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 2 ... Front substrate, 4 ... Back substrate, 6 ... Side wall, 8 ... Spacer, 10 ... Vacuum envelope (display panel), 12 ... Phosphor screen, 14 ... Metal back, 16 ... Electron emission element, 18 ... Wiring, 20, 30, 40 ... getter layer, 50 ... wall.

Claims (9)

In a display device having a vacuum envelope in which a front substrate and a rear substrate are opposed to each other,
A display device, wherein a getter layer is provided at a place other than the phosphor light emitting portion of the front substrate.   The display device according to claim 1, wherein the getter layer is a divided pattern.   The display device according to claim 1, wherein the getter layer has a thickness of 100 nm or more.   The display device according to claim 1, wherein the rear substrate is provided with an electron-emitting device that emits the phosphor. A front substrate having a large number of phosphor pixels on its inner surface;
A peripheral substrate is sealed to the front substrate to form a vacuum envelope, and a rear substrate having a large number of electron-emitting devices corresponding to the phosphor pixels on the inner surface thereof;
A getter layer provided on the inner surface of the front substrate so as not to overlap the phosphor pixels;
A display device comprising: The metal back is electrically divided into a plurality of regions,
6. The display device according to claim 5, wherein the getter layer is divided so as not to be electrically connected between the divided metal backs.   The display device according to claim 5, wherein the getter layer has a thickness of 100 [nm] or more.   The display device according to claim 5, wherein the base of the getter layer has an uneven surface. A front substrate having a large number of phosphor pixels on its inner surface;
A peripheral part is sealed to the front substrate to form a vacuum envelope, and a rear substrate having a large number of electron-emitting devices corresponding to the phosphor pixels on the inner surface thereof;
A getter layer provided on the inner surface of the front substrate at a position deviated from the trajectory of the electron beam emitted from the electron-emitting device;
A display device comprising:

Images