KR100848921B1 - Flat panel fluorescent lamp - Google Patents

Abstract

A flat panel fluorescent lamp is provided to increase a brightness level of the fluorescent lamp by isolating a UV(Ultra-Violet) generating space from a fluorescent layer. A flat panel fluorescent lamp includes upper and lower substrates(20,30), which are bonded to each other and form a discharge space. A discharge gas is filled in the discharge space. A discharge electrode(32) is formed on an upper surface or an outer surface of the lower substrate. A fluorescent layer(22) is formed on an outer surface of the upper substrate and generates a visual ray, when excited by a UV beam generated in the discharge space. The fluorescent layer is formed by applying a mixture of a fluorescent member and a resin material on an outer surface of the upper substrate. A film, which is formed by mixing the fluorescent member with the resin material, is attached to the outer surface of the upper substrate.

Description

Flat panel fluorescent lamp

1 is a cross-sectional view showing an example of a conventional flat fluorescent lamp

2 is a cross-sectional view showing another example of a conventional flat fluorescent lamp

Figure 3 is a cross-sectional view showing an embodiment of a flat fluorescent lamp according to the present invention

4 and 5 are cross-sectional views showing another embodiment of the present invention.

<Explanation of symbols for the main parts of the drawings>

20: upper substrate 22: phosphor layer

30: lower substrate 32: discharge electrode

34: dielectric layer 40: upper substrate

42 phosphor layer 50 lower substrate

52 tube 54 discharge electrode

56: CCFL 58: UV LED

The present invention relates to a flat plate fluorescent lamp, and more particularly, to a flat plate fluorescent lamp which has a long lifespan due to no phosphor damage caused by ultraviolet rays and a compact structure, which can reduce manufacturing costs and greatly improve the uniformity of light emission. .

As a back light unit (BLU) of a conventional liquid crystal display (LCD), a linear light source such as a cold cathode fluorescent lamp (CCFL) is installed on the thickness surface of the light guide plate, and the linear light source is diffused to the surface light source. However, recently, flat fluorescent lamps are mainly used to increase the size of LCDs and to improve light efficiency.

1 is a cross-sectional view showing an example of a conventional flat fluorescent lamp. Referring to this, the upper substrate 1 and the lower substrate 3 of glass material are disposed to face each other, and a plurality of discharge electrodes 5 are formed on the upper surface or the outer surface of the lower substrate 3. Dielectric Barrier Discharge (DBD) type lamps such as the embodiment of FIG. 1 form a discharge electrode 5 on the upper surface of the lower substrate 3, and a dielectric layer (B) on the surface of the discharge electrode 5 for polarization. 7) is formed, and the external electrode fluorescent lamp (EEFL) is formed with a discharge electrode 5 on the outside of the lower substrate (3). A phosphor is coated on the lower surface of the upper substrate 1 to form the phosphor layer 9, and a protective film 11 for protecting the phosphor layer 9 from ultraviolet rays may be further provided. A spacer 13 is interposed between the upper substrate 1 and the lower substrate 3 to form a discharge channel therein, and a discharge gas such as mercury or an inert gas is injected into the discharge channel. The flat fluorescent lamp is turned on by the ultraviolet rays generated inside the discharge channel by the discharge electrode 5 to excite the phosphor of the phosphor layer 9 to generate visible light.

However, since the phosphor is directly exposed to ultraviolet rays, damage to the phosphor caused by ultraviolet rays occurs, which causes a decrease in the brightness of the lamp or shorten the life of the lamp according to the use time. In addition, a protective film 11 may be provided to protect the phosphor layer 9, and there is a limit to protecting the phosphor according to the thickness constraint of the protective film 11, and due to the additional configuration of the protective film 11 or the like, There is a problem that the thickness of the fluorescent lamp is thick and the manufacturing cost is increased.

2 is a cross-sectional view showing another example of a conventional flat fluorescent lamp, and shows a flat fluorescent lamp of a type in which a plurality of CCFLs are arranged in parallel. Referring to this, a plurality of CCFLs are arranged in parallel between the upper substrate 2 and the lower substrate 4 of the flat plate, and each CCFL has a tubular body 8 into which discharge gas is injected, and within the tubular body 8. It consists of the phosphor layer 10 formed by apply | coating a fluorescent substance to a wall surface, and the cathode 12 arrange | positioned inside the tube 8.

Even in such CCFL parallel arrangement type flat fluorescent lamps, as mentioned above, there is a problem in that the brightness of the lamp is gradually reduced or the life is shortened due to the damage of the phosphor by ultraviolet rays inside each CCFL. In addition, the light generated in each CCFL has a non-uniform problem with respect to the entire plane, and as shown in order to solve this problem, as the additional configuration of the diffusion sheet 6 is required, the structure is complicated and the manufacturing cost is increased. There is a problem.

The present invention has been proposed to solve the above problems, by applying a phosphor on the outer surface of the flat fluorescent lamp or by attaching a fluorescent sheet to prevent damage to the phosphor by ultraviolet rays, protection of the phosphor or diffusion sheet, etc. It is not necessary to configure the structure of the structure can be compactly designed, and its object is to provide a flat fluorescent lamp that greatly improved the uniformity of light emission.

According to an embodiment of the present invention for achieving the above object, the upper substrate and the lower substrate which is disposed opposite to each other and the both ends are joined to form a discharge space therein and the discharge gas is filled in the discharge space, and A flat fluorescent lamp is provided that includes a discharge electrode formed on an upper surface or an outer surface of a lower substrate, and a phosphor layer formed on an outer surface of the upper substrate and excited by ultraviolet rays generated in the discharge space to generate visible light. .

According to another embodiment of the present invention, the upper substrate and the lower substrate disposed to face each other, a plurality of ultraviolet lamps disposed between the upper substrate and the lower substrate, and formed on the outer surface of the upper substrate and each of the ultraviolet rays There is provided a flat fluorescent lamp comprising a phosphor layer which is excited by ultraviolet light generated in a lamp to generate visible light.

In this case, the ultraviolet lamp is a CCFL composed of a tube body in which discharge gas is enclosed and a discharge electrode disposed in the tube body.

The ultraviolet lamp can also be a UV LED.

In the present invention, the phosphor layer is formed by attaching a film formed by mixing phosphor and a resin material to the outer surface of the upper substrate, or by applying a material mixed with phosphor and resin to the outer surface of the upper substrate.

In addition, the resin may be selected from the group comprising epoxy, PMMA, PC.

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

The present invention is to protect the phosphor from damage caused by ultraviolet rays, characterized in that the phosphor layer is formed on the outer surface of the panel rather than having the phosphor in the internal discharge space of the panel. In the following description, the internal structure of the phosphor layer and the discharge space, which constitute the features of the present invention, will be mainly described, and a detailed description of the general structure of the flat fluorescent lamp will be omitted.

3 is a cross-sectional view showing an embodiment of a flat fluorescent lamp according to the present invention, Figures 4 and 5 is a cross-sectional view showing another embodiment of the present invention.

First, an embodiment of the present invention will be described with reference to FIG. 3. As shown, the upper substrate 20 and the lower substrate 30 are disposed opposite each other. The upper substrate 20 and the lower substrate 30 are each formed by molding a transparent material, preferably a glass material into a flat plate. Although not shown, the edge portions of the upper substrate 20 and the lower substrate 30 are joined by bonding means, and discharge gas is enclosed in a space formed between the upper substrate 20 and the lower substrate 30. Sealing the discharge gas is connected to the exhaust pipe to one side of the panel formed by joining the upper substrate 20 and the lower substrate 30, after making the discharge space inside the panel vacuum through the exhaust pipe, mercury or Xe or Ne and It consists of injecting the same inert gas.

A plurality of discharge electrodes 32 are disposed on the upper surface of the lower substrate 30. The discharge electrode 32 is formed by printing a conductive metal material on the upper surface of the lower substrate 30 as an insulator by screen printing or the like. As shown, a dielectric layer 34 may be further formed on the top surface of the discharge electrode 32. When the dielectric layer 34 is formed, polarization between the discharge electrodes 32 can be induced even by disposing the discharge electrodes 32 densely. The discharge electrode 32 is connected to a power supply device (not shown) and receives power from the power supply device to generate a discharge in a discharge space inside the upper substrate 20 and the lower substrate 30. At this time, ultraviolet rays are generated in the discharge space. Although not shown, the discharge electrode 32 may be formed outside the lower substrate 30. That is, the present invention is also applicable to the EEFL forming an electrode outside the discharge space.

The phosphor layer 22 is formed on the outer surface of the upper substrate 20. Preferably, the phosphor layer 22 is formed by applying a phosphor to the outer surface of the upper substrate 20 or by attaching a film containing the phosphor. The phosphor is emitted by UV (Ultra Violet) and is a common phosphor that emits red, green, blue light and the like, and the phosphor is excited by ultraviolet rays generated inside the panel to generate visible light. The phosphor layer 22 may be formed by applying a mixture of a resin such as epoxy, PMMA, PC, and the like to the outer surface of the upper substrate 20 and baking the upper substrate 20. In addition, the phosphor layer 22 is formed by mixing a resin such as epoxy, PMMA, PC, and the like into a phosphor to prepare a separate film, and then attaching the film to the outer surface of the upper substrate 20 by light-transmissive adhesive means. You may. As the phosphor layer 22 is formed on the outer surface of the upper substrate 20 as described above, the phosphors included in the phosphor layer 22 are not directly exposed to ultraviolet rays formed in the discharge space, and thus the phosphors are damaged by ultraviolet rays. Can be protected from.

4 and 5 illustrate another embodiment of the present invention, in which a plurality of ultraviolet lamps are disposed in a panel, and FIG. 4 illustrates an embodiment in which a plurality of CCFLs are disposed in a panel. 5 shows an embodiment in which a plurality of UV LEDs are disposed inside the panel.

As shown, the upper substrate 40 and the lower substrate 50 are disposed opposite to each other to form a panel is the same as the above-described embodiment. At this time, unlike the above embodiment in which the discharge gas is enclosed in the space between the upper substrate 40 and the lower substrate 50 or a direct discharge electrode is installed, a plurality of spaces are provided in the space between the upper substrate 40 and the lower substrate 50. Independent UV lamps may be arranged. In other words, each of the ultraviolet lamps disposed in the inner space may generate ultraviolet rays, and the phosphor layer 42 formed on the outer surface of the upper substrate 40 may be configured to convert them into visible light. In this embodiment, since the discharge gas is not sealed between the upper substrate 40 and the lower substrate 50, a vacuum and an exhaust structure for sealing the discharge gas are unnecessary as compared with the above embodiment.

As shown in FIG. 4, a plurality of linear light sources may be disposed between the upper substrate 40 and the lower substrate 50. Preferably, a plurality of CCFLs 56 may be arranged in parallel. Each CCFL 56 has the following structure. First, a plurality of pipe bodies 52 constituting each CCFL 56 are arranged in parallel on the lower substrate 50, and discharge gas such as mercury or Xe or Ne is enclosed in each pipe body 52. A discharge electrode 54 is disposed inside each tube 52. For example, the discharge electrode 54 in the CCFL 56 is a cold cathode. At this time, phosphor is not applied to the inner wall of each CCFL 56. Thus, each CCFL 56 generates only ultraviolet light.

Meanwhile, as shown in FIG. 5, a plurality of point light sources may be disposed between the upper substrate 40 and the lower substrate 50. In this case, the point light source may have a structure that does not turn on in a discharge method. For example, a plurality of UV LEDs 58 may be disposed between the upper substrate 40 and the lower substrate 50.

In the embodiment shown in FIGS. 4 and 5, the phosphor layer 42 is formed on the outer surface of the upper substrate 40. The phosphor layer 42 is formed by applying a mixture of phosphors, resins such as epoxy, PMMA, PC, and the like to the outer surface of the upper substrate 40 or by attaching a film in the same manner as in the above-described embodiment. Since the phosphor layer 42 is disposed in a space partitioned from the ultraviolet rays generated by the respective tubular lamps, the phosphor layer 42 is not damaged by the ultraviolet rays. In addition, when the phosphor layer 42 is attached in the form of a film, it also serves to diffuse the light generated from the plurality of linear light sources, there is no need to attach a separate diffusion sheet.

The flat fluorescent lamp of the present invention as described above is partitioned from the space inside the panel in which ultraviolet rays are generated to form phosphor layers 22 and 42 on the outer surface of the upper substrates 20 and 40. Therefore, the phosphor contained in the phosphor layers 22 and 42 may not be damaged by ultraviolet rays, thereby preventing shortening of the life of the lamp due to the damage of the phosphor. In addition, it is not necessary to include a protective film for protecting the phosphor layers 22 and 42 or a diffusion layer for diffusing light generated from a linear light source, and thus the structure is compact, and the phosphor is placed outside the tube as compared with the phosphor layer inside the tube. It is easy to form a layer to simplify the work process. Therefore, a compact and lightweight design of the LCD can be made possible, and the manufacturing cost can be greatly reduced. In addition, it is possible to solve problems such as lowering of uniformity of light emission or lowering of brightness due to partial damage of a phosphor, which has been generated in a conventional flat lamp, thereby improving the uniformity of light emission and maintaining a high brightness level even for long time use. The flat fluorescent lamp of the present invention is characterized by partitioning the discharge space and the phosphor layers 22 and 42 in which ultraviolet rays are generated, regardless of the type of flat fluorescent lamp such as DBD type lamp, EEFL, CCFL, etc. It can be applied to all flat fluorescent lamps in which UV is generated by converting UV light into visible light and lighting.

The present invention described above is not limited to the above-described embodiments and the accompanying drawings, and various substitutions, modifications, and changes are possible in the technical field of the present invention without departing from the technical spirit of the present invention. It will be clear to those of ordinary knowledge.

As described above, the flat fluorescent lamp according to the present invention forms a phosphor layer on the outer surface of the upper substrate, and spatially partitions the space where the ultraviolet light is generated and the phosphor layer, thereby preventing damage to the phosphor by the ultraviolet light. Increasing the life of the lamp, structurally compact, aims to reduce the size and weight of the LCD, greatly reduce the manufacturing cost, and has the effect of maintaining the uniformity and high luminance level even in long-term use.

Claims (11)

The upper substrate and the lower substrate which are disposed to face each other and are joined to each other to form a discharge space therein, and in which the discharge gas is filled, discharge electrodes formed on the upper or outer surface of the lower substrate, and the upper substrate. And a phosphor layer which is formed on an outer surface and is excited by ultraviolet rays generated in the discharge space to generate visible light, wherein the phosphor layer is formed by applying a mixture of phosphor and resin material to an outer surface of an upper substrate. Or a film formed by mixing a phosphor and a resin material on an outer surface of the upper substrate. delete delete The method of claim 1, The resin is a flat fluorescent lamp, characterized in that selected from the group comprising epoxy, PMMA, PC. The method of claim 1, A plurality of discharge electrodes are disposed on the upper surface of the lower substrate, and a dielectric layer for polarization of the discharge electrode is formed on the discharge electrode. The upper substrate and the lower substrate disposed to face each other, a plurality of ultraviolet lamps disposed between the upper substrate and the lower substrate, and formed on an outer surface of the upper substrate and excited by ultraviolet rays generated by the respective ultraviolet lamps. It comprises a phosphor layer for generating visible light, wherein the phosphor layer is formed by applying a mixture of phosphor and resin material on the outer surface of the upper substrate, or a film formed by mixing the phosphor and resin material on the outer surface of the upper substrate Flat fluorescent lamp is formed by attaching to. The method of claim 6, The ultraviolet lamp is a flat fluorescent lamp, characterized in that the CCFL consisting of a discharge body is filled with the discharge gas therein, and the discharge electrode disposed inside the tube. The method of claim 6, The ultraviolet lamp is a flat fluorescent lamp, characterized in that the UV LED. delete delete The method according to any one of claims 6 to 8, The resin is a flat fluorescent lamp, characterized in that selected from the group comprising epoxy, PMMA, PC.

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