KR20070102117A - Field emission device - Google Patents

Abstract

An electric field emission device is provided to adjust light emissions of the device by replacing a spacer for maintaining an interval of upper and lower substrates by an anode electrode and a cathode electrode. An upper substrate(120) and a lower substrate(110) are faced to each other and are sealed by a sealing member(140) to form a vacuum container. Plural anode electrodes(122) and cathode electrodes(112) intersect each other between the upper and lower substrates to maintain an interval of the upper and lower substrates. A phosphor layer(124) is formed on both sides of the anode electrode, and an emitter(116) is formed on both sides of the cathode electrodes.

Description

Field emission device

1 is a cross-sectional view for explaining a field emission device according to the prior art;

2 is a plan view for explaining a field emission device according to an embodiment of the present invention;

3 is a perspective view showing a part of the field emission device according to an embodiment of the present invention.

The present invention relates to a field emission device, and more particularly to a field emission device that can easily control the amount of emitted light.

Field emission devices (FEDs) are generally used as field emission displays, field emission light sources, and the like. The electrode configuration of the field emission device generally consists of a three pole structure (anode, cathode and gate electrode) or a two pole structure (anode and cathode electrode). The field emission device operates as a display device when a high voltage (˜10 kV) is applied to the anode electrode and a data voltage necessary for light emission and image realization is applied to the cathode and gate electrodes. Meanwhile, the field emission device operates as a light source when a high voltage is applied to the anode electrode and a voltage necessary for light emission is applied to the cathode and the gate electrode. The voltage applied here is typically in the form of a pulse. Even in the bipolar structure, a high voltage for light emission is applied to the anode in the form of direct current (DC) or pulse.

1 is a cross-sectional view illustrating a field emission device according to the prior art.

Referring to FIG. 1, the field emission device is provided with a cathode electrode 12 on the lower substrate 10. An insulating layer 15 having a plurality of holes spaced at regular intervals is provided on the cathode electrode 12. The gate electrode 14 is provided on the insulating layer 15 except for the plurality of holes. An emitter 16 in the form of a micro tip is provided for each of the provided holes spaced at regular intervals from the insulating film 15. A sealing member 40 is provided at the edge of the lower substrate 10. An upper substrate 20 is provided on the sealing member 40 to face the lower substrate 10. An anode electrode 22 is provided on the upper substrate 20. The fluorescent film 24 is provided on the anode electrode 22.

When the field emission device emits electrons (dashed arrow) from the emitter 16, the emitted electrons collide with the fluorescent film 24 attached to the anode electrode 22 provided on the upper substrate 20 to emit light. Solid line arrows) to implement a predetermined image or light source. In order to maximize the electric field under the same voltage, the emitter 16 provided on the cathode electrode 12 is formed in a pointed structure such as a tip.

On the other hand, the spacer 30 of the field emission device is a special component that cannot be seen in other flat panel display technologies, and is one of the problems that cause the commercialization of the field emission device. Some of the electrons from the emitter 16 on the cathode electrode 12 hits the spacer 30, and secondary electrons are generated in the spacer 30 hit by the electrons. As a result, the spacer 30 near the anode electrode 22 is charged with positive charge and dissipates electrons directed toward the spacer 30 and the fluorescent film 24 adjacent to the spacer 30 toward the spacer 30. It greatly reduces the uniformity of light, and also causes electrical arcing to reduce the performance and life of the field emission device.

The field emission device as described above has a problem in that the amount of emitted light cannot be controlled because the area (or the amount of electron emission) that can emit light is determined when the size of the upper substrate and the lower substrate is determined. In addition, the amount of electron emission is reduced due to the presence of the spacer, and electrical arcing occurs due to distortion of the electron beam, thereby reducing the performance and lifespan of the field emission device. In addition, since the anode electrode has a structure attached to the upper substrate, the electrons collide with the anode electrode, and heat generated in the anode electrode escapes only to the upper substrate. Accordingly, there is also a problem that heat generated in the anode electrode is difficult to escape easily.

SUMMARY OF THE INVENTION The present invention has been made in an effort to provide a field emission device capable of adjusting the amount of emitted light of the field emission device.

In order to achieve the above technical problem, the present invention provides a field emission device. The field emission element is arranged so as to vertically intersect the upper and lower substrates and the upper and lower substrates facing each other so as to form a vacuum container by sealing by a sealing member, and a plurality of alternating anode and cathode electrodes are arranged. Include.

The anode electrode and the cathode electrode can maintain a gap between the upper substrate and the lower substrate.

Fluorescent films may be provided on both sides of the anode electrode. Emitters may be provided on both sides of the cathode electrode.

The gate electrode may further include a gate electrode insulated from the cathode electrode.

The lower substrate may include a reflective film for reflecting light. The reflecting film may be made of a mirror or a prism.

The lower substrate may include an anode connection electrode and a cathode connection electrode for applying power to the anode electrode and the cathode electrode, respectively, on an upper surface thereof. In addition, the lower substrate may further include a gate connection electrode on the upper surface thereof for applying power to the gate electrode.

The amount of emitted light can be adjusted by the gap between the anode electrode and the cathode electrode which are arranged alternately.

The amount of emitted light can be adjusted by the height of the anode electrode and the cathode electrode.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. However, the present invention is not limited to the embodiments described herein and may be embodied in other forms. Rather, the embodiments introduced herein are provided so that the disclosure may be made thorough and complete, and to fully convey the spirit of the invention to those skilled in the art. Therefore, the shape of the elements in the drawings are exaggerated to emphasize a clearer description. In the drawings, like reference numerals designate like elements that perform the same function.

2 is a plan view illustrating a field emission device according to an exemplary embodiment of the present invention.

Referring to FIG. 2, the field emission device includes an upper substrate 120 and a lower substrate 110, and an upper substrate 120 and a lower substrate 110 that face each other to form a vacuum container by sealing by the sealing member 140. And a plurality of anode electrodes 122 and cathode electrodes 112 arranged alternately, perpendicularly between each other.

The plurality of anode electrodes 122 and the cathode electrodes 112 that are alternately arranged may maintain a gap between the upper substrate 120 and the lower substrate 110. Accordingly, the role of the spacer 30 of FIG. 1 may be replaced in the related art. As such, by replacing the spacer using the anode electrode 122 and the cathode electrode 112, the electrical arcing due to the reduction of the amount of electron emission and the distortion of the electron beam caused by the presence of the spacer can be prevented. Thus, the performance and lifespan of the field emission device can be extended.

The anode electrode 122 may be provided with a fluorescent film 124 on both sides. The cathode electrode 112 may be provided with an emitter 116 on both sides thereof. The amount of electron emission may be proportional to the number of cathode electrodes 112 provided. Unlike the prior art in which the emitter 116 is provided only on one side of the cathode electrode 112, the amount of electron emission can be increased because the emitter 116 is provided on both sides of the cathode electrode 112. In addition, the fluorescent film 124 may be provided on both sides of the anode electrode 122 to efficiently process the electron beams coming from both directions of the anode electrode 122. Accordingly, as the amount of emitted electrons increases, the amount of emitted light can ultimately increase.

An insulating film 115 having a plurality of holes spaced at regular intervals is provided on the cathode electrode 112. The gate electrode 114 is provided on the insulating layer 115 except for the plurality of holes. A hole micro tip shaped emitter 116 is provided on the insulating film 115 spaced apart at regular intervals. Thus, the gate electrode 114 insulated from the cathode electrode 112 may be further provided.

The lower substrate 110 may be provided with a reflective film 118 for reflecting light. The reflective film 116 may be formed of a mirror or a prism. The reflective film 118 may be formed on the bottom surface or the top surface of the lower substrate. Accordingly, the light (solid line arrow) generated at the portion of the anode electrode 122 adjacent to the lower substrate 110 may be emitted through the upper substrate 120. When a prism is used as the reflective film 118, the reflected light can be directed by a prism in a constant direction (upper substrate direction).

In the field emission device, when electrons are emitted from the emitter 116 (dashed arrows), the emitted electrons collide with the fluorescent film 124 attached to the anode electrode 122 to emit light (solid arrows), thereby providing a predetermined image. Or it may be a device for implementing a light source. In order to maximize the electric field under the same voltage, the emitter 116 provided on the cathode electrode 112 may be formed in a pointed structure such as a tip. The emitter 116 may not be shaped like a tip, but may be shaped like a surface of a carbon nanotube (CNT) film.

The amount of emitted light may be controlled by the gap between the anode electrode 122 and the cathode electrode 112 arranged alternately. This is because the amount of emitted electrons is proportional to the number of cathode electrodes 112 provided, and the amount of emitted light can be proportional to the number of anode electrodes 122 that convert the emitted electron beam into light. This is because the number of emitters 116 provided on the cathode electrode 122 is proportional to the number of cathode electrodes 122. Accordingly, the light emission amount may increase as the interval between the anode electrode 122 and the cathode electrode 112 that are alternately arranged becomes narrower.

The amount of emitted light may be adjusted by the heights of the anode electrode 122 and the cathode electrode 112. This is because the amount of emitted electrons is proportional to the area of the cathode electrode 112 provided, and the amount of emitted light can be proportional to the area of the anode electrode 122 that converts the emitted electron beam into light. This is because, depending on the area of the cathode electrode 112, the number of emitters 116 that can be provided on the cathode electrode 112 increases. Accordingly, as the height of the anode electrode 122 and the cathode electrode 112 increases, the amount of emitted light may increase.

3 is a perspective view showing a part of the field emission device according to an embodiment of the present invention.

Referring to FIG. 3, the lower substrate 110 includes an anode connection electrode 111a and a cathode connection electrode 111c for applying power to the anode electrode 122 and the cathode electrode 112 on the upper surface thereof. Can have In addition, the lower substrate 112 may further include a gate connection electrode 111g for applying power to the gate electrode 114 on an upper surface thereof.

The anode electrode 122, the gate electrode 114, and the cathode electrode 112 are connected to each other by using a silver paste, and the anode electrode contact 130a, the gate electrode contact 130g, and the cathode electrode contact 130c, respectively. ) May be electrically connected to the anode connecting electrode 111a, the gate connecting electrode 111g, and the cathode connecting electrode 111c, respectively. The cathode electrode 112 and the gate electrode 114 may be electrically insulated by an insulating film (not shown, 115 in FIG. 2).

The field emission device according to the embodiment of the present invention described above may replace the spacer of the prior art by a plurality of anode electrodes and cathode electrodes disposed alternately while being vertically disposed between the upper substrate and the lower substrate. Accordingly, unlike the prior art, even if the size of the upper substrate and the lower substrate is determined, the gap between the plurality of anode electrodes and the cathode electrodes arranged vertically between the upper substrate and the lower substrate and interposed is adjusted, or the anode electrode. And by adjusting the height of the cathode itself, it is possible to provide a field emission device that can easily adjust the amount of emitted light of the field emission device.

In addition, the presence of the spacer reduces the amount of electron emission and prevents electrical arcing due to distortion of the electron beam, thereby providing a field emission device capable of extending the performance and life of the field emission device.

In addition, since the anode electrode has a structure disposed between the upper substrate and the lower substrate, it may have a structure that the heat generated from the anode electrode can easily escape to both the upper substrate and the lower substrate by colliding with the anode electrode and electrons. . Accordingly, it is possible to provide a field emission device that can be thermally stable.

As described above, according to the present invention, the anode electrode and the cathode electrode of the field emission device replace the spacer, thereby providing a field emission device capable of easily adjusting the amount of emitted light of the field emission device.

Claims (11)

An upper substrate and a lower substrate facing each other so as to constitute a vacuum container by sealing by a sealing member; And And a plurality of anode electrodes and a cathode electrode disposed alternately between the upper substrate and the lower substrate, the anode and the cathode. The method of claim 1, And the anode electrode and the cathode electrode maintain a gap between the upper substrate and the lower substrate. The method of claim 2, A field emission device, characterized in that the fluorescent film is provided on both sides of the anode electrode. The method of claim 2, And emitters provided on both sides of the cathode electrode. The method of claim 4, wherein And a gate electrode insulated from the cathode electrode on the cathode electrode. The method of claim 1, And the lower substrate includes a reflective film for reflecting light. The method of claim 6, The reflection film is a field emission device, characterized in that consisting of a mirror or a prism. The method of claim 1, And the lower substrate has an anode connection electrode and a cathode connection electrode for applying power to the anode electrode and the cathode electrode, respectively, on an upper surface thereof. The method of claim 5, And the lower substrate further includes a gate connection electrode on an upper surface thereof for applying power to the gate electrode. The method of claim 1, The amount of emitted light is controlled by the gap between the anode and the cathode electrode disposed crosswise. The method of claim 1, The amount of emitted light is controlled by the height of the anode electrode and the cathode electrode.

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