KR20070051583A - Cold cathode fluorescent lamp, method for manufacturing thereof and liquid crystal display apparatus having the same - Google Patents

Abstract

Disclosed are a cold cathode fluorescent lamp capable of preventing breakage, a method of manufacturing the same, and a liquid crystal display device having the same. The cold cathode fluorescent lamp is a lamp tube in which discharge gas is injected, a fluorescent layer formed on the inner surface of the lamp tube, internal electrodes disposed inside both ends of the lamp tube, connected to the internal electrodes, and lead wires drawn out of the lamp tube; It includes a shock absorbing layer formed on the outer surface of both ends of the lamp tube so that the lead wire is exposed. Therefore, since the shock absorbing layer absorbs stress and shock, it is possible to prevent breakage of the cold cathode fluorescent lamp due to impact.

Description

Cold Cathode Fluorescent Lamp, Manufacturing Method Thereof and Liquid Crystal Display Having It {COLD CATHODE FLUORESCENT LAMP, METHOD FOR MANUFACTURING THEREOF AND LIQUID CRYSTAL DISPLAY APPARATUS HAVING THE SAME}

1 is a perspective view showing a cold cathode fluorescent lamp according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view taken along the line II ′ of FIG. 1.

3 is an exploded perspective view illustrating a liquid crystal display according to an exemplary embodiment of the present invention.

4 is a perspective view illustrating a state in which the cold cathode fluorescent lamp and the lamp socket of FIG. 3 are separated.

5 is a perspective view illustrating a state in which the cold cathode fluorescent lamp and the lamp socket of FIG. 4 are combined;

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

100: cold cathode fluorescent lamp 110: lamp tube

120: fluorescent layer 130: internal electrode

140: lead wire 150: shock absorbing layer

200: liquid crystal display 300: backlight assembly

400: storage container 500: power transmission board

520 lamp socket 800 optical member

900: display unit 910: liquid crystal display panel

The present invention relates to a cold cathode fluorescent lamp, a manufacturing method thereof, and a liquid crystal display device having the same, and more particularly, to a cold cathode fluorescent lamp capable of absorbing an external impact and improving the airtightness of a sealing portion of a lamp, and a manufacturing method thereof. It relates to a liquid crystal display having the same.

In general, a liquid crystal display is a flat panel display that displays an image using liquid crystal, which is thinner and lighter than other display devices, and has a low driving voltage and low power consumption. This has been widely used throughout the industry.

Such a liquid crystal display device requires a backlight assembly for supplying light to the liquid crystal display panel because the liquid crystal display panel for displaying an image is a non-light emitting device that does not emit light by itself.

The backlight assembly is largely classified into an edge type and a direct type according to the position of the light source. The edge type is a structure in which a lamp unit is disposed on the side of the light guide plate, and is advantageous in thinning a product. On the other hand, the direct type has a structure in which a plurality of lamps are arranged under the liquid crystal display panel, which is advantageous for high brightness of a product. Therefore, a direct type backlight assembly is employed in large products requiring high brightness.

Lamps used in direct backlight assembly are mainly used as long and cold cylindrical Cathode Fluorescent Lamp (CCFL). Since the cold cathode fluorescent lamp has an electrode disposed inside the lamp tube, the cold cathode fluorescent lamp has a lead wire connected to the electrode and drawn out to the outside. In order to apply the lamp driving power from the inverter to the electrode, the lamp wire connected to the inverter is connected to the lead wire through a soldering process. Alternatively, the lead wire may be directly coupled to a lamp socket connected to an inverter to receive a lamp driving power. In this method, since the cold cathode fluorescent lamp is connected to the inverter through the lamp socket without using the lamp wire, the process can be shortened and the assembly of the product is improved.

However, when the cold cathode fluorescent lamp is directly coupled to the lamp socket, the assembly tolerance makes it difficult to completely fix the cold cathode fluorescent lamp and the lamp socket. Therefore, the cold cathode fluorescent lamp is flowed in the lamp socket to generate stress. If this phenomenon continues, the lead wire is bent, or the airtightness of the sealing portions formed at both ends of the lamp tube is lowered, resulting in poor lighting of the cold cathode fluorescent lamp and reduced lifespan.

Accordingly, the present invention has been made in view of such a problem, and the present invention provides a cold cathode fluorescent lamp capable of absorbing external shocks and improving the airtightness of the sealing portion of the lamp tube.

The present invention also provides a method for producing the cold cathode fluorescent lamp described above.

In addition, the present invention provides a liquid crystal display device having the cold cathode fluorescent lamp described above.

The cold cathode fluorescent lamp according to an aspect of the present invention described above comprises a lamp tube in which discharge gas is injected, a fluorescent layer formed on an inner surface of the lamp tube, internal electrodes disposed inside both ends of the lamp tube, and the internal electrode; And a shock absorbing layer formed on an outer surface of both ends of the lamp tube to expose the lead wire and the lead wire drawn out of the lamp tube.

According to an aspect of the present invention, there is provided a method of manufacturing a cold cathode fluorescent lamp, the method including: manufacturing a lamp tube, forming a fluorescent layer on an inner surface of the lamp tube, and internal electrodes connected to lead wires at both ends of the lamp tube. Arranging, injecting a discharge gas into the lamp tube, sealing the lamp tube so that the lead wire is drawn out, and forming shock absorbing layers on outer surfaces of both ends of the lamp tube.

According to an aspect of the present invention, a liquid crystal display includes a backlight assembly and a display unit configured to display an image by receiving light from the backlight assembly. The backlight assembly includes a storage container, lamp sockets disposed at both sides of the storage container, and cold cathode fluorescent lamps coupled to the lamp sockets and arranged in parallel with each other. The cold cathode fluorescent lamp is connected to a lamp tube in which discharge gas is injected, a fluorescent layer formed on an inner surface of the lamp tube, internal electrodes disposed inside both ends of the lamp tube, and the internal electrode, and external to the lamp tube. And a shock absorbing layer formed on outer surfaces of both ends of the lamp tube so as to expose the lead wires drawn out.

According to such a cold cathode fluorescent lamp, a manufacturing method thereof and a liquid crystal display having the same, since the shock absorbing layer is formed on the outer surface of both ends of the cold cathode fluorescent lamp, it is possible to protect the cold cathode fluorescent lamp from external stress and impact, The airtightness of the sealing part of a lamp tube can be improved.

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

1 is a perspective view showing a cold cathode fluorescent lamp according to an embodiment of the present invention, Figure 2 is a cross-sectional view taken along the line II 'of FIG.

1 and 2, the cold cathode fluorescent lamp 100 includes a lamp tube 110 into which discharge gas is injected, a fluorescent layer 120 formed on an inner surface of the lamp tube 110, and an amount of the lamp tube 110. The amount of the lamp tube 110 is connected to the internal electrode 130 and the internal electrode 130 disposed inside the end portion so that the lead wire 140 and the lead wire 140 drawn out of the lamp tube 110 are exposed. It includes a shock absorbing layer 150 formed on the outer surface of the end.

The lamp tube 110 is made of a transparent glass material so that visible light generated therein may be transmitted. The discharge gas for emitting light of the cold cathode fluorescent lamp 100 is injected into the lamp tube 110. For example, the discharge gas includes gases such as mercury (Hg), neon (Ne), xenon (Xe), argon (Ar) and the like. Mercury (Hg) generates ultraviolet rays by discharge. Neon (Ne), xenon (Xe), and argon (Ar) are ionized by the discharge to generate secondary electrons to increase the amount of ultraviolet rays generated, and the level of the discharge voltage required to cause the discharge by the penning effect Reduce power consumption

The lamp tube 110 has an elongated cylindrical shape. Alternatively, the lamp tube 110 may have a U shape.

The fluorescent layer 120 is formed on the inner surface of the lamp tube 110. The fluorescent layer 120 is excited by the ultraviolet rays generated by the discharge gas through the plasma discharge to emit visible light.

The internal electrode 130 is disposed inside both ends of the lamp tube 110. The internal electrode 130 has a hollow cylindrical shape for increasing the surface area. As the surface area of the internal electrode 130 increases, the amount of electron emission increases and luminance increases, and the amount of mercury decrease decreases, thereby extending the life. In contrast, the internal electrode 130 may be formed in various shapes to increase the surface area.

The internal electrode 130 may be made of various metal materials. For example, the internal electrode 130 is made of metal such as nickel (Ni), molybdenum (Mo), niobium (Nb), or the like. These metals have a low work function value. Therefore, the internal electrode 130 using these metals can be discharged even with a relatively low driving voltage compared to using metals having a high work function.

The lead wire 140 has one end connected to the internal electrode 130 and the other end thereof drawn out of the lamp tube 110 to provide a lamp driving power to the internal electrode 130.

The shock absorbing layer 150 is formed on outer surfaces of both ends of the cold cathode fluorescent lamp 100. The shock absorbing layer 150 is made of a material capable of absorbing shock. For example, the shock absorbing layer 150 is made of silicon. The shock absorbing layer 150 prevents the cold cathode fluorescent lamp 100 from flowing after being coupled to the lamp socket 520 of FIG. 3, and prevents the cold cathode fluorescent lamp 100 from being damaged by an external impact. Since the shock absorbing layer 150 is formed to be completely in contact with the outer surfaces of both ends of the lamp tube 110 to be integrated with the lamp tube 110, the airtightness of the sealing portion of the cold cathode fluorescent lamp 100 is ensured. In addition, since the shock absorbing layer 150 is filled in the minute cracks that may be formed around the sealing part, the crack may be prevented from being prevented and the discharge gas may be prevented from escaping through the minute cracks.

Looking at the process of the cold cathode fluorescent lamp 100 generates light, first, the lamp driving power provided from the outside is applied to the internal electrode 130 via the lead wire 140. When the lamp driving power is applied to the internal electrode 130, electrons are emitted from the internal electrode 130, and the emitted electrons collide with discharge gas such as mercury (Hg) existing in the lamp tube 110. The discharge gas is ionized by the collision with the electrons, thereby creating a plasma environment inside the lamp tube 110. At this time, light having a predetermined wavelength, for example, ultraviolet rays, is generated. The fluorescent layer 120 formed on the inner surface of the lamp tube 110 is excited by the ultraviolet light to generate visible light.

Hereinafter, a method of manufacturing a cold cathode fluorescent lamp according to an embodiment of the present invention will be described.

First, after the lamp tube 110 having an elongated shape is manufactured, the fluorescent layer 120 is formed on an inner surface of the lamp tube 110.

Thereafter, the internal electrodes 130 connected to the lead wires 140 are disposed in both ends of the lamp tube 110.

Thereafter, a discharge gas is injected into the lamp tube 110 in a vacuum state, and both ends of the lamp tube 110 are sealed to lead the lead wire 140 to the outside. A part of the lead wire 140 is disposed inside the lamp tube 110 by sealing the lamp tube 110, and the other part is disposed outside the lamp tube 110. On the other hand, the injection of the discharge gas may be made before the internal electrode 130 is disposed.

Thereafter, the shock absorbing layer 150 is formed on outer surfaces of both ends of the lamp tube 110.

Meanwhile, the shock absorbing layer 150 may be formed through a dipping method. Specifically, both ends of the lamp tube 110 are immersed in the shock absorbing layer forming material and taken out to remove the shock absorbing layer forming material formed on the outer surface of the lead wire 140. The shock absorbing layer forming material is completely adhered to the outer surface of both ends of the lamp tube 110 and the outer surface of the lead wire 140, the shock absorbing layer forming material formed on the outer surface of the lead wire 140 during the oxidation removal process of the lead wire 140 Can be removed at the same time. As a result, the shock absorbing layer 150 is formed on the outer surfaces of both ends of the lamp tube 110.

3 is an exploded perspective view illustrating a liquid crystal display according to an exemplary embodiment of the present invention. In the present embodiment, since the cold cathode fluorescent lamp 100 is the same as that shown in Figs. 1 and 2, the same reference numerals are used, and detailed description thereof will be omitted.

Referring to FIG. 3, the liquid crystal display 200 according to an exemplary embodiment of the present invention includes a display unit 900 that receives an image from the backlight assembly 300 and the backlight assembly 300 to display an image. do. The backlight assembly 300 includes a storage container 400, a power transmission substrate 500, an inverter 600, cold cathode fluorescent lamps 100, a side mold 700, and an optical member 800.

The storage container 400 includes a bottom portion 410 and a side portion 420 extending from an edge of the bottom portion 410 to provide a storage space. The cathode cathode fluorescent lamps 100, the side mold 700, the optical member 800, and the like are accommodated in the accommodation space. Holes 412 are formed in the bottom part 410 in correspondence with the lamp sockets 520 so that the lamp sockets 520 may be disposed through the bottom part of the bottom part 410. Although not illustrated, a reflective sheet for reflecting light incident from the cold cathode fluorescent lamp 100 may be disposed on the upper portion of the bottom portion 410. On the other hand, when the bottom 410 itself is made of a material having a high light reflectance, the reflective sheet may be removed.

The power transmission substrate 500 includes a substrate body 510 and lamp sockets 520 coupled to the substrate body 510. A pair of power transmission substrates 500 are disposed on the bottom surface of the bottom portion 410 so as to correspond to the holes 412 formed in the bottom portion 410. The power transmission board 500 receives the lamp driving power from the inverter 600 connected through the power line 610 and transmits the lamp driving power to the lamp sockets 520.

The substrate body 510 has a plate shape. The substrate body 510 includes a transmission wire (not shown) electrically connected to the lamp sockets 520 to transmit lamp driving power.

The lamp sockets 520 fix the cold cathode fluorescent lamps 100 and supply power to the cold cathode fluorescent lamps 100. The lamp sockets 520 are coupled to the substrate body 510 in a row, and are disposed to pass through holes 412 of the bottom 410 of the storage container 400 from the bottom to the top. The lamp sockets 520 are coupled to the substrate body 510 such that the lamp sockets 520 are spaced at equal intervals from each other for equally spaced arrangements between the cold cathode fluorescent lamps 100. On the contrary, the lamp sockets 520 may be coupled to the substrate body 510 at different intervals to differently space the cold cathode fluorescent lamps 100.

The inverter 600 is disposed on the rear surface of the storage container 400 to apply the lamp driving power to the power transmission substrate 500. Specifically, the inverter 600 changes the low potential AC power applied from the outside into a high potential AC power suitable for driving the cold cathode fluorescent lamps 100 to output the lamp driving power through the power line 610. It is applied to the power transmission board 500.

The pair of side mold 700 is disposed in the receiving container 400 to face each other. The side mold 700 covers the portion where the shock absorbing layer 150 is formed of the cold cathode fluorescent lamps 100 that are substantially free of light, thereby removing dark portions and improving luminance uniformity. In addition, the side mold 700 supports the optical member 800 disposed above, and guides the storage position of the optical member 800.

The optical member 800 improves the characteristics of the light incident from the cold cathode fluorescent lamps 100. Edges of the optical member 800 are respectively seated on the top surface of the pair of side molds 700. The optical member 800 includes a diffusion plate 810 for diffusing light and at least one optical sheet 820 for improving the characteristics of the light.

The diffusion plate 810 diffuses the light generated from the cold cathode fluorescent lamps 100 to improve luminance uniformity. The diffusion plate 810 has a rectangular plate shape having a predetermined thickness. The diffusion plate 810 is spaced apart from the cold cathode fluorescent lamps 100 at a predetermined interval by the support of the side mold 700. For example, the diffusion plate 810 may be made of polymethyl methacrylate (PMMA), and may include a diffusion agent for diffusing light.

The optical sheet 820 is disposed above the diffuser plate 810 and improves the characteristics of light diffused through the diffuser plate 810. The optical sheet 820 may include a diffusion sheet 822 for diffusing the light diffused through the diffusion plate 810 once again to improve luminance uniformity. In addition, the optical sheet 820 may include a prism sheet 824 for concentrating the light diffused through the diffusion plate 810 and the diffusion sheet 822 in the front direction to improve the front brightness of the light. Meanwhile, optical sheets 820 having various functions may be added or removed according to luminance characteristics required for the backlight assembly 300.

The display unit 900 receives light from the backlight assembly 300, and displays a liquid crystal display panel 910 to display an image, and a data and gate printed circuit board 920 to brake a driving signal for driving the liquid crystal display panel 910. , 930). In this case, the data printed circuit board 920 is connected to the data tape carrier package (TCP) 940 and the gate printed circuit board 930 is connected to the liquid crystal display panel 910 through the gate TCP 950. ) Is electrically connected.

The liquid crystal display panel 910 includes a first substrate 912, a second substrate 914 coupled to face the first substrate 912, and a liquid crystal disposed between the first substrate 912 and the second substrate 914. Layer 916.

The first substrate 912 is a transparent glass substrate in which thin film transistors (hereinafter referred to as TFTs) to which pixel electrodes are connected are formed in a matrix form. The second substrate 914 is a glass substrate in which RGB pixels for color are formed by a thin film process, and a common electrode made of a transparent conductive material is formed.

Therefore, when power is applied to the TFT, the liquid crystal display panel 910 forms an electric field between the pixel electrode and the common electrode, and is interposed between the first substrate 912 and the second substrate 914 by the electric field. The arrangement of the liquid crystal molecules of the liquid crystal layer 916 is changed, and the transmittance of light is changed according to the arrangement change of the liquid crystal molecules to display a desired image.

The top chassis 450 surrounds the edge of the liquid crystal display panel 910 and is coupled to the side portion 420 of the storage container 400 to fix the liquid crystal display panel 910 to the upper portion of the backlight assembly 300.

4 is a perspective view illustrating a state in which the cold cathode fluorescent lamp and the lamp socket of FIG. 3 are separated, and FIG. 5 is a perspective view illustrating a state in which the cold cathode fluorescent lamp and the lamp socket of FIG. 4 are coupled to each other.

4 and 5, the lamp socket 520 fixes and supports the cold cathode fluorescent lamp 100, and supplies lamp driving power to the cold cathode fluorescent lamp 100. The lamp socket 520 may include a socket body 522 for supporting the cold cathode fluorescent lamp 100, a conductive terminal 524 for applying a lamp driving power to the cold cathode fluorescent lamp 100, and a cold cathode fluorescent lamp ( Socket lock 526 for securing 100 to lamp socket 520.

The socket body 522 is made of an insulating material and supports both ends of the cold cathode fluorescent lamp 100. The socket body 522 has a curved surface 522a corresponding to the shape of the end portion of the cold cathode fluorescent lamp 100 in which the shock absorbing layer 150 is formed.

The curved surface 522a is formed such that its radius of curvature is larger than the radius of the lamp tube 110 alone and smaller than the radius of the lamp tube 110 including the shock absorbing layer 150. This is because when the cold cathode fluorescent lamp 100 is coupled to the socket body 522, the shock absorbing layer 150 is contracted to fit the radius of curvature of the curved surface 522a, and thus the socket body 522 is coupled with the socket body 522. This is because the flow of the combined cold cathode fluorescent lamp 100 is prevented. Therefore, the cold cathode fluorescent lamp 100 is stably fixed to the lamp socket 520, thereby preventing breakage of the lead wire 140 due to stress and impact.

Alternatively, the radius of curvature of the curved surface 522a may be the same as the radius of the lamp tube 110 including the shock absorbing layer 150.

The conductive terminal 524 is disposed in the socket body portion 522 at a position corresponding to the lead wire 140 of the cold cathode fluorescent lamp 100. The conductive terminal 524 applies a lamp driving power supply to the cold cathode fluorescent lamp 100. Specifically, the conductive terminal 524 is composed of a pair of metal terminals facing each other, electrically connected to the power transmission substrate 500, coupled to the lead wire 140 of the cold cathode fluorescent lamp 100 to drive the lamp Apply power.

The socket lock part 526 is made of an insulating material and is coupled to a position corresponding to where the conductive terminal 524 is disposed in the socket body part 522. The socket locking portion 526 is movable up and down and is moved downward to be coupled with the socket body portion 522. At this time, the socket locking part 526 presses the conductive terminal 524 to strongly bind the conductive terminal 524 and the lead wire 140. At this time, both ends of the lamp tube 110 on which the shock absorbing layer 150 is formed are strongly coupled to the curved surface 522a of the lamp socket 520. Therefore, the cold cathode fluorescent lamp 100 is prevented from flowing in the lamp socket 520, and the stress of the lead wire 140 due to the flow is prevented. In addition, the shock absorbing layer 150 absorbs the shock transmitted from the outside, thereby preventing damage to the cold cathode fluorescent lamp 100.

According to such a backlight assembly and a liquid crystal display having the same, shock absorbing layers are formed at both ends of the cold cathode fluorescent lamp to prevent stress due to the flow of the cold cathode fluorescent lamp when combined with the lamp socket. Therefore, it is possible to prevent breakage of the cold cathode fluorescent lamp, such as bending of the lead wire due to repeated stress, lowering the airtightness of the sealing portion. In addition, the formation of the shock absorbing layer may provide an effect of supplementing fine cracks formed at both ends of the lamp tube.

In the detailed description of the present invention described above with reference to the preferred embodiments of the present invention, those skilled in the art or those skilled in the art having ordinary skill in the art will be described in the claims to be described later It will be understood that various modifications and variations can be made in the present invention without departing from the scope of the present invention.

Claims (8)

A lamp tube into which discharge gas is injected; A fluorescent layer formed on an inner surface of the lamp tube; Internal electrodes disposed inside both ends of the lamp tube; A lead wire connected to the internal electrode and drawn out of the lamp tube; And And a shock absorbing layer formed on outer surfaces of both ends of the lamp tube to expose the lead wires. The cold cathode fluorescent lamp of claim 1, wherein the impact absorbing layer is made of silicon. Manufacturing a lamp tube; Forming a fluorescent layer on an inner surface of the lamp tube; Disposing internal electrodes connected to lead wires at both ends of the lamp tube; Injecting a discharge gas into the lamp tube and sealing the lamp tube such that the lead wire is drawn out; And Forming a shock absorbing layer on the outer surface of both ends of the lamp tube manufacturing method of a cold cathode fluorescent lamp. The method of claim 3, wherein the forming of the shock absorbing layer is Dipping both ends of the lamp tube into a shock absorbing layer forming material; And And removing the impact absorbing layer forming material formed on the outer surface of the lead wire. The method of claim 4, wherein the shock absorbing layer forming material formed on an outer surface of the lead wire is simultaneously removed during an oxidation removal process of the lead wire. The method of manufacturing a cold cathode fluorescent lamp of claim 3, wherein the impact absorbing layer is made of silicon. A backlight assembly including a storage container, lamp sockets disposed at both sides of the storage container, and cold cathode fluorescent lamps coupled to the lamp sockets and arranged in parallel with each other; And It includes a display unit for receiving the light from the backlight assembly to display an image, The cold cathode fluorescent lamp A lamp tube into which discharge gas is injected; A fluorescent layer formed on an inner surface of the lamp tube; Internal electrodes disposed inside both ends of the lamp tube; A lead wire connected to the internal electrode and drawn out of the lamp tube; And And an impact absorbing layer formed on outer surfaces of both ends of the lamp tube to expose the lead wires. The liquid crystal display device according to claim 7, wherein the shock absorbing layer is made of silicon.

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