KR100307445B1 - Surface light source device - Google Patents

Abstract

PURPOSE: A surface light source device is provided to realize high efficiency and high luminance through the entire surface uniformly and extend the lifespan of electrodes and the surface light source device. CONSTITUTION: A surface light source device includes a sealed container formed of a transparent material, upper and lower panels formed at top and bottom surfaces in the sealed container and formed with second electrodes, first electrodes(4) in the shape of a plurality of wire mounted in a space between the upper and lower panels, and a gas mixture injected into the space, wherein the upper panel includes the second electrodes attached to an inner top surface of the sealed container, a dielectric layer formed on an inner surface of the second electrode layer, and a fluorescent film(7) doped on the dielectric layer, and the lower panel includes a reflection film attached to an inner bottom surface of the sealed container, the second electrode layer attached with a reflection film on an inner side, a dielectric layer formed on an inner surface of the second electrode layer, and a fluorescent film doped on the dielectric layer.

Description

Cotton light source device

1 is a perspective view of a surface light source device according to the prior art,

2 is a perspective view of the surface light source device of the present invention,

3 is a cross-sectional view of the upper panel and the lower panel of the surface light source device of the present invention,

4 is a cross-sectional view showing another embodiment of the flat surface light source device of the present invention;

5 is a perspective view showing another embodiment of a flat surface light source device of the present invention, and

6 is a cross-sectional view showing a typical structure of an AC plasma display panel using gas discharge.

* Explanation of symbols for the main parts of the drawings

1. airtight container 2. top panel

3. Lower panel 4. First electrode

5. Second electrode 6. Glass dielectric layer

7. Fluorescent film 8. Reflective film

9. Glass bulkhead 10. Electrode

11. Enclosure 12. Substrate

13. Sealed glass 14. Horizontal electrode

15. Vertical Electrode 16. Magnesium Oxide Layer

17. Gas mixture

The present invention relates to a flat surface light source device that can be used for the rear light source or general illumination of a liquid crystal panel.

There are many ways to get light using electrical energy. Light bulbs using filaments, light bulbs using fluorescent materials, light bulbs using fluorescent materials, neon signs using gas discharges, electroluminescence, light emitting diodes, etc. It belongs to the case by the method of obtaining. Devices according to these methods may be used for lighting or as a light source, but may be used as a display device for reproducing an image of an advertisement or a video medium.

The surface light source device is to be used as a flat light source of the LCD device, or to use a general light source as a light source can have a considerable luminous intensity should be able to exhibit an appropriate illuminance.

In the conventional surface light source device, a lamp used as a light source of the rear light source or the projection arch of the display device is a fatal disadvantage, and there is a problem that the lamp surface does not have uniform brightness throughout. In surface light source devices operating on the same principle as fluorescent lamps, this problem occurs mainly because the discharge paths formed between the electrodes are not properly designed. This is because the discharge is necessary as a means for causing the emission and movement of electrons to collide with the mercury atoms, and desirable emission can be achieved only when the emission and flow of electrons can be made uniform throughout. In addition, since a large space is discharged by two electrodes in general, a relatively high voltage must be applied to the electrode, and thus there is a problem in that the electrode is easily deteriorated and its life is shortened.

An example of a surface light source device according to the prior art is shown in FIG. In order to discharge the whole inside of the flat plate with two electrodes 10, the glass partition 9 was formed and the discharge path was formed over the whole, and the sealing hole 11 for gas injection is formed in the side wall. However, in general, since the discharge is generated through the shortest distance between the electrodes 10, it has a non-uniform luminous intensity, that is, a low luminous intensity, at a corner portion relatively far from the discharge path. In addition, in the electrode 10 used, there is a disadvantage that can easily be degraded because the surface area of the electrode 10 is small.

Accordingly, an object of the present invention is to provide a flat surface light source device having high brightness with uniform brightness and high efficiency.

Another object of the present invention is to provide a flat surface light source device having a longer service life by extending the life of the electrode.

It is another object of the present invention to provide a flat surface light source device in which the structure is relatively simple and the manufacturing process is relatively simple.

The surface light source device of the present invention includes a sealed container made of a transparent material, an upper panel attached to upper and lower surfaces of the sealed container, and having a second electrode formed thereon, and a lower panel opposed thereto, and an inner space between the two panels. It comprises a first electrode installed in the form of a wire and a gas mixture injected into the inner space, the upper panel is a second electrode layer attached to the upper inner surface of the sealed container, the inner surface of the second electrode layer And a fluorescent layer applied to an inner surface of the dielectric layer, wherein the upper panel is applied to the dielectric layer formed on the inner surface of the second electrode layer attached to the upper inner surface of the airtight container and the inner surface of the dielectric layer. It is configured to include a fluorescent film, wherein the lower panel is a reflective film attached to the lower inner surface of the sealed container, the reflective magnet A second electrode attached to the gun side, is configured to include the first dielectric layer formed on the inner surface of the second electrode layer, and a fluorescent film which is applied to the internal surface of the dielectric layer.

With this configuration, since the electrode is formed over the entire surface, discharge is generated uniformly at a relatively low voltage, and the entire light emitting surface exhibits uniform luminance. Incidentally, effects such as increased efficiency and ease of manufacture can be expected.

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

3 is a cross-sectional view of an upper panel and a lower panel of the surface light source device of the present invention.

A second electrode 5 is formed on the upper panel 2, a dielectric layer 6 made of a transparent material such as glass is formed therein, and a fluorescent film 7 is coated on the inner surface thereof. A reflective film 8 is formed below the lower panel 3, and a second electrode 5 is formed on an upper surface thereof, that is, an inner surface thereof, and a glass and an upper surface of the second electrode 5 are formed. A dielectric layer 6 made of the same material is formed, and a fluorescent film 7 is coated on the upper surface of the dielectric layer 6 again. In the space between the upper panel 2 and the lower panel 3, the first electrode 4 is installed in the form of a net or a plurality of wires. In addition, the gas mixture 17 is injected into the internal space, and mercury atoms emit ultraviolet rays when they collide with electrons generated during gas discharge, thereby emitting the fluorescent film 7.

The second electrode 5 is made of a transparent conductive material, and the dielectric layer 6 is an insulating layer of a film, and thus acts as a capacitor when a voltage is applied. Therefore, the reflecting film 8 is formed to reflect the emitted light to improve the brightness, and is formed of a material such as aluminum or silver, similar to a general mirror for reflecting visible light. The gas mixture 17 injected into the sealed container 1 is a rare gas flow, that is, an inert gas and a mercury gas. Mercury atoms in the gas mixture 17 are excited by collision with the moving electrons to generate a dimension.

In such a structure, the dielectric strength of the dielectric layer 6, the voltage used, the distance between the electrodes, the thickness of the dielectric layer 6, and the like are related matters to be designed. The capacitor capacitance formed by the dielectric layer 6 is determined by the dielectric constant of the dielectric and increases as the dielectric constant becomes larger. The thickness of the dielectric layer 6 is determined in consideration of the dielectric strength of the dielectric. Dielectric strength is a measure of the ability of a material to retain energy at high voltages. The unit of dielectric strength is defined as the voltage per unit length. If an excessively high voltage is applied to the dielectric, electrons or ions will flow through the dielectric, and if this force exceeds the dielectric strength, the dielectric material will begin to break down and current will flow. In other words, the insulation capacity is lost.

The light emission principle of the surface light source device of the present invention is that when the high frequency or pulse voltage is applied to the first electrode 4 and the second electrode 5, the whole is formed, and the electrons that may be partially included in the gas mixture 17 are accelerated to When collided with neon atoms in the mixture 17, electrons are released while ionizing neon atoms. As the number increases, the electrons excite the mercury atoms other than neon atoms. Photons are emitted from neon atoms and ultraviolet rays are emitted from mercury atoms. When the electrode is in the form of a mesh, when the opening of the first electrode 4 or the electrode is in the form of a wire, discharge occurs between each wire and electrons are emitted. At this time, when mercury gas is excited by the accelerated electrons, ultraviolet rays are emitted. The phosphor is excited by the ultraviolet rays emitted in this way. The excited phosphors emit visible light. This is generally due to the property that phosphors absorb short wavelengths of high energy and emit long wavelengths of light with low energy.

In addition, in the present invention, direct discharge is not generated between the first electrode 4 and the second electrode 5 by using an alternating current and using an electrode insulated with a dielectric, but in the gas mixture 17 when a voltage is applied. The ionization of neon and argon occurs, and the electrons thus formed are allowed to collide with the mercury atoms while moving in the direction of the electric field formation by the alternating current. This phenomenon occurs according to the principle of gas discharge. In other words, the present invention combines the principle of electron emission by gas discharge with the principle of light emission by fluorescent material to form a surface light source device. Thus, some rays should be viewed as emitted as a result of gas discharge.

Insulating the electrode by the dielectric allows the formation of an electric field uniformly due to the applied voltage at the same time as the capacitor for storing electrical energy is formed. That is, the ionization and discharge of the gas in the internal space are generated uniformly and the flow of electrons is uniformly generated. Of course, since the high frequency is used as the power source, the flow of electrons vibrates in the inner space and excites mercury atoms.

Regarding the gas discharge, a cross-sectional view showing a typical structure of the plasma display panel using the gas discharge is shown in FIG. With reference to FIG. 6, the principle of the general gas discharge and the structure for the gas discharge will be briefly described in relation to the plasma display.

Briefly, the gas discharge principle is as follows. When the electric field is formed through the gas, electrons in the gas are plasticized by the electric field and collide with the neon atoms while moving, and the neon atoms emit electrons and are converted into positive neon ions. As this process is repeated, the number of electrons increases. Fully excited neon neon atoms emit photons.

The main difference between the direct current display and the alternating current display in the gas discharge display is in direct contact with the gas in the former case and insulated from the electrode gas in the latter case. The former requires an external resistor to limit the current, while the latter does not require an external resistor because the current is limited by the formation of a voltage on the dielectric. Of course, an AC voltage can also be used for a direct current system. As an example of the AC plasma display device, the interval between the internal space where gas discharge is generated is 100 μm, and the thickness of the glass dielectric layer 6 insulating the electrode and it is 25 μm in the shape of a thin film, neon and 0.1% of argon. Was used as the discharge gas. In addition, a magnesium oxide (MgO) layer 16, which is a refractory material, is formed in the form of a thin film having a thickness of 200 nm. However, magnesium oxide cannot achieve the same effect when mercury is used for the gas mixture 17. Two glass plates are used as the substrate 12 for supporting the band-shaped horizontal electrode 14 and the vertical electrode 15 and the respective glass dielectric layers 6, and a solder is formed between the two dielectric layers 6. The glass was used as the sealing glass 13 and sealed.

4 shows another embodiment of the flat surface light source device of the present invention. In this embodiment, the fluorescent film 7 is applied to a separate glass plate or the upper inner surface of the airtight container 1 in order to facilitate the application of the fluorescent film 7. In such a form, ultraviolet rays emitted from mercury atoms excited by electrons pass through the thin film-shaped upper panel 2 to reach the fluorescent film 7. Ultraviolet light is generally blocked by glass. FIG. 5 shows another embodiment of the flat surface light source device of the present invention. In this case, the first electrode 4 is provided in a mesh shape so that gas discharge is generated more efficiently. It is similar to the case of FIG. 3 except that the shape of the electrode is different, and light emission is performed on the same principle. When installing the panel or the electrode in the above-described embodiments, the spacer member may be formed by a transparent insulating material such as glass, although not shown, if necessary.

According to the surface light source device of the present invention configured as described above, a surface light source device capable of realizing high efficiency and conduction is provided. In addition, it exhibits uniform luminance over the entire surface of the light source and extends the life of the electrode, thereby extending the life of the surface light source device. The surface light source device which is simple in structure and which can be thinned is provided. Therefore, it is used as a rear overcurrent of the LCD display device, which not only makes the display device lighter but also enables the uniform display of high brightness.

Claims (4)

A flat surface light source device, comprising: a sealed container made of a transparent material, an upper panel attached to upper and lower surfaces of the sealed container, and having a second electrode formed therein, and a lower panel facing the lower panel; It comprises a first electrode installed in the form of a wire and a gas mixture injected into the inner space, the upper panel is a second electrode layer attached to the upper inner surface of the sealed container, the inner surface of the second electrode layer And a dielectric layer to be formed and a fluorescent film applied to the dielectric surface, wherein the lower panel includes a reflective film attached to a lower inner surface of the airtight container, a second electrode gun to which the reflective mug is attached to an inner side, and the second electrode. And a fluorescent film applied to the inner surface of the dielectric layer and a dielectric layer formed on the inner surface of the layer. The surface light source device according to claim 1, wherein the first electrode is in the form of a mesh. In a flat surface light source device, an upper panel formed of a transparent material and installed in upper and lower portions of an airtight container in which a fluorescent film is coated on an upper inner side thereof, and having a second electrode formed thereon, and a lower panel opposite thereto, between the two panels. A first electrode installed in a plurality of wires in an inner space of the gas mixture and a gas mixture injected into the inner space, and the upper panel includes a second electrode layer and a dust agent attached to an upper inner surface of the airtight container. It comprises a dielectric layer formed of a material such as glass formed on the inner surface of the two-electrode layer, The lower panel includes a dielectric layer formed of a material such as a glass that is formed on the inner surface of the second electrode layer and the second electrode layer attached to the inner surface of the reflective film, still attached to the lower inner surface of the sealed container Cotton light source device composed. 4. The surface light source device according to claim 3, wherein the first electrode has a mesh shape.