KR101157951B1 - Backlight Unit - Google Patents

Abstract

The present invention relates to a backlight unit that forms a common electrode in a gripper shape to facilitate contact with external electrodes, and at the same time changes the structure of a structure for seating and supporting a lamp to reduce sound noise. A plurality of lamps arranged at regular intervals with electrodes at both ends outside the tube, a gripper formed to contact and fix the electrodes of the lamps for each lamp, and a lower portion formed in one direction at both ends of the lamps; An instrument, an upper instrument formed on both ends of the lamps opposite the lower instrument, a sidewall instrument formed on a surface of the upper instrument and supporting between the lamps in a space between the upper instrument and the lower instrument; An upper portion of the lower fixture and a projection located below the lamp and an image including the protrusion It characterized by yirueojim including lower Enclosures common electrode line formed through the upper portion.

Supporter Side, Rib, Sound Noise, External Electrode Fluorescent Lamp (EEFL)

Description

BACKLIGHT UNIT [0001]

1 is a perspective view of a direct backlight unit according to the prior art;

2 is a partial structural diagram of applying an electrode to a lamp in a direct backlight unit according to the prior art

3A illustrates an external electrode lamp used for a backlight

FIG. 3B is an equivalent circuit diagram of the lamp of FIG. 3A

4 is a perspective view of a backlight unit according to an embodiment of the present invention;

5A and 5B are enlarged perspective views of portions 'A' and 'B' of FIG. 4.

6 is a perspective view of a common electrode applied to the present invention;

7 is a side cross-sectional view showing a common electrode end of the backlight unit according to an embodiment of the present invention.

8 is a cross-sectional side view illustrating a common electrode end of a backlight unit according to another exemplary embodiment of the present invention.

Explanation of symbols on the main parts of the drawings

50a, 50b: electrode 51: lamp

53 common electrode 54 lower mechanism

55: screw 56: wire

57: circular electrode 58: gripper

59: common electrode line 60: stopper

61: hole 70: upper fixture

71: side wall mechanism 80: upper mechanism

81 side wall fixture 85 common electrode line

90: lamp 95: gripper

105: lower fixture

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid crystal display device. In particular, the common electrode is formed as a gripper to facilitate contact with external electrodes, and at the same time, the structure of a structure for mounting and supporting the lamp is changed to sound noise. It is related with the backlight unit which reduced.

CRT (Cathode Ray Tube), one of the commonly used display devices, is mainly used for monitors such as TVs, measuring devices, and information terminal devices.However, due to the weight and size of the CRT itself, Could not respond actively to demands.

Therefore, in the trend of miniaturization and weight reduction of various electronic products, CRTs have certain limitations in weight and size, and are expected to replace them. Liquid crystal displays (LCDs) and gas discharges using electro-optic effects are expected. Plasma Display Panel (PDP) and Electro Luminescence Display (ELD) using the electroluminescent effect, and the like, among them, research on liquid crystal display (LCD) is being actively conducted.

Recently, it has been developed enough to perform a role as a flat panel display device and is used not only for monitors of laptop computers but also for monitors and large information displays of desktop computers, and the demand for liquid crystal displays is continuously increasing. It is true.

Since the liquid crystal display is a light-receiving device that displays an image using incoming light, an external light or a separate light source for irradiating light onto the liquid crystal panel, that is, a backlight unit is necessary.

In general, a backlight unit used as a light source of a liquid crystal display is classified into an edge type and a direct type according to a method of disposing a lamp.

In the double edge method, a lamp unit is installed on a side of a light guide plate for guiding light, and the lamp unit includes a lamp that emits light, a lamp holder inserted at both ends of the lamp to protect the lamp, and an outer circumferential surface of the lamp. It is provided with a lamp reflector that wraps and one side is fitted to the side of the light guide plate to reflect the light emitted from the lamp toward the light guide plate.

The direct method was developed mainly as the size of the liquid crystal display device became larger than 20 inches, and arranged a plurality of lamps in a row on the lower surface of the diffusion plate to direct light directly to the front of the liquid crystal panel. .

In the backlight unit, a cold cathode fluorescent lamp (CCFL) or an external electrode fluorescent lamp (EEFL) is used as a light source.

In this case, the cold cathode fluorescent lamp (CCFL) operates at a high brightness of about 30000 cd / m 2 and the life of the lamp is a problem. In particular, when used in the edge method, the cold cathode fluorescent lamp (CCFL) itself emits high luminance, but the luminance of the panel is low, which is not suitable for a large screen panel. In the direct type, the cold cathode fluorescent lamp (CCFL) can not be connected in parallel to be driven by a single inverter. Because of the large spacing between them, a special reflector is needed and at the same time the distance between the diffuser and the lamp is increased in order to obtain uniform brightness, so the thickness of the panel is large.

On the other hand, when using an external electrode fluorescent lamp (EEFL) it is possible to drive a plurality of external electrode fluorescent lamps by a single inverter connected in parallel. The reason is that since the electrode of the external electrode fluorescent lamp is not exposed to the discharge space and exists outside the glass tube, the real current does not flow to the electrode, wall charges are accumulated on both electrode portions, and the reverse voltage is caused by wall charge across the lamp. Discharge is stopped by the formation of, followed by another lamp being discharged and similarly the wall charge is formed, and then another lamp is discharged sequentially so that a plurality of lamps emit light by one inverter. However, when the external electrode fluorescent lamp (EEFL) is driven using an inverter that outputs a sine wave used for driving the cold cathode fluorescent lamp (CCFL), the wall charge cannot be effectively controlled, so high brightness is driven by driving high frequency. Implement

On the other hand, the electrode structure of the external electrode fluorescent lamp (EEFL) has a variety of methods, such as belt (belt) type, glass tube junction type of metal cap, and inflated space at both ends of the glass tube.

Hereinafter, the direct type backlight unit according to the related art will be described with reference to the accompanying drawings.

1 is a perspective view of a direct backlight unit according to the prior art, and FIG. 2 is a partial structural diagram of applying an electrode to a lamp in the direct backlight unit according to the prior art.

As shown in FIG. 1 and FIG. 2, a direct backlight unit according to the related art has a plurality of lamps 1 having electrodes 2 formed at both ends of the inside of the tube, and predetermined intervals in accordance with the length of the lamps 1. A lower mechanism 3 having a plurality of grooves formed on one surface thereof to accommodate both ends of the plurality of lamps 1, a lower reflector 4 formed on the lower mechanism 3, and a lower portion thereof. A plurality of lamp holders 5 fastened to the ends of the two lamps 1 in pairs to fix and support the lamps together with the fixture 3, and lamps to fix the lamp holders 5 1) It comprises an upper mechanism (6) formed along the edges of both ends.

At this time, the lamp 1 is a cold cathode fluorescent lamp (CCFL: Cold Cathode Fluorescent Lamp), as shown in Figure 2, the electrode (2) formed at both ends of the tube (tube) and the electrode (2) inside the tube It consists of an inner lead line 7 for applying a voltage to the inner lead line, and an outer lead line (not shown) connected to the inner lead line 7 for applying a voltage from the outside.

At this time, the inner lead wire 7 and the out lead wire are connected by soldering 9.

The out lead wire is fixed / connected to a wire 10 and a shrink tube 11 connected to an inverter (not shown) provided on the rear surface of the lower mechanism 3.

However, in order to apply the driving voltage to the lamp 1 in the backlight unit having the above configuration, the inner lead line 7 and the out lead line are soldered (9) and connected, and the shrink tube 11 is inserted, transported, and operated in a module work process. When an external force such as handling (especially bending force) is applied, the connected portion (the soldered portion 9) of the inner lead wire 7 and the out lead wire is most stressed.

As a result of this stress, the soldered part may fall off, causing the lead wire to be disconnected.

As such, when a lead wire is disconnected, various defects such as lighting failure, spark generation, and lighting failure leakage occur.

Therefore, the prior art which solders and connects the inner lead wire 7 and the out lead wire has a limit.

However, in the backlight unit of the cold-cathode fluorescent lamp type including an electrode inside such a tube, since the connector is connected to the power supply line of the lamp and connected to the driving circuit, a separate connector is required for each lamp, and the wiring is complicated. In order to reduce the thickness of the backlight, the power lead wire is bent and connected to the connector, which not only reduces work efficiency, but also requires additional work for this purpose, thereby increasing process time and decreasing productivity.

In addition, the connection between the electrode and the connector must be drilled through a hole through the outer case, and both electrodes of the lamp must be inserted into the hole so that both electrodes of the lamp are exposed to the outside of the outer case, thereby reducing the work efficiency and the lamp. Maintenance and repair are difficult.

As such, in the cold cathode fluorescent lamp system, in order to prevent a problem caused by using a plurality of lamps, an external electrode fluorescent lamp (EEFL: External Electrode Fluorescent Lamp) constituting an electrode outside the lamp may be configured. have.

FIG. 3A is a diagram illustrating an external electrode lamp used for a backlight, and FIG. 3B is an equivalent circuit diagram of the lamp of FIG. 3A.

In the external electrode lamp EEFL, first and second external electrodes 32a and 32b are formed at both ends of the tube 31 as shown in FIG. 3A, and the inner wall of the tube 31 is fluorescent. The material is coated, and mercury is injected into the tube 31.

The external electrode lamp is driven using wall charges formed on the first and second external electrodes 32a and 32b formed at both ends, and both ends serve as capacitors C1 and C2. This equivalent circuit is shown in Figure 3b.

The external electrode lamp is a state in which one end of the tube 31 is open, mercury (Hg) is injected into the open end, and a fluorescent material is injected and coated to cover the open end with a transparent glass. Is produced.

Recently, when the backlight unit is configured in a direct manner using a plurality of lamps as a light source, it is a trend to use an external electrode fluorescent lamp as a light source. The reason is that an inverter is required for each number of lamps when the cold cathode fluorescent lamp is used, and the process is burdensome in forming an electrode and applying a voltage signal thereto.

The present invention has been made to solve the above problems, by using an external electrode fluorescent lamp as a light source, to form a common electrode for applying a voltage signal to the fluorescent lamp in the gripper type to facilitate contact with the external electrode. In addition, at the same time to change the structure of the structure for mounting and supporting the lamp to provide a backlight unit that reduces the sound noise (sound noise).

The backlight unit of the present invention for achieving the above object comprises a plurality of lamps arranged at regular intervals with electrodes on both ends of the outside of the tube, and a gripper formed to contact and fix the electrodes of the lamps for each lamp And a lower mechanism formed in one direction below both ends of the lamps, an upper mechanism formed on both ends of the lamps opposite the lower mechanism, and formed on a surface of the upper mechanism, and a space between the upper mechanism and the lower mechanism. And a common electrode line formed over the side wall mechanism supporting the space between the lamps, the upper side of the lower mechanism, and a protrusion located below the lamp and an upper portion of the lower mechanism including the protrusion.

The protrusion has a height of 0.2 ~ 0.4mm.

The gripper includes one or more slots.

The common electrode line includes a first common electrode line formed at an inner end of the lamp and a second common electrode line formed at an outer end of the lamp.

It further comprises a plurality of screws (Screw) for fixing the common electrode to the lower mechanism, a wire connected to the inverter and a circular electrode formed to surround the screw to connect the common electrode with a wire connected to the inverter.

And a stopper formed on the second common electrode line corresponding to the end of each lamp and a plurality of holes formed in a portion to which the screw is to be fastened.

The stopper is formed vertically at the end of the second common electrode line.

Hereinafter, a backlight unit according to a preferred embodiment of the present invention will be described with reference to the accompanying drawings.

4 is a perspective view of a backlight unit according to an exemplary embodiment of the present invention. FIGS. 5A and 5B are enlarged perspective views of portions 'A' and 'B' of FIG. 4, and FIG. 6 is a perspective view of a common electrode applied to the present invention. . 7 is a cross-sectional side view illustrating an end portion of a common electrode of a backlight unit according to an exemplary embodiment of the present invention.

4 to 7, the backlight unit of the present invention includes a plurality of lamps 51 arranged at regular intervals with electrodes 50a and 50b at both ends outside the tube, and for each of the lamps 51. A common electrode 53 formed of a gripper 58 in contact with and fixing the electrodes 50a and 50b of the lamp and a common electrode line 59a and 59b integrally formed with the gripper 58; A supporter side bottom 54 formed in one direction below both ends of the lamps 51 to seat the common electrode 53, and an upper device formed opposite the lower device 75 on both ends of the lamps. (supporter side top) 54 (54a, 54b) and a side wall mechanism projecting from the surface of the upper mechanism 70 to support the space between the lamps 51 in the space between the upper and lower mechanisms 70, 54 (supporter side rib) 71 and the lower mechanism 54 Comprises a portion formed over the common electrode line (59a, 59b).

The common electrode 53 is connected to both ends of the gripper 58 and the gripper 58 formed in the lamp array direction to form first and second common electrode lines 59a and 59b formed in a direction perpendicular to the lamp array direction. It is formed to include. At this time, the first common electrode line 59a is formed inside the lamp 51 from the first and second common electrode lines 59a and 59b, and the second one is formed at the end of the lamp 51. Common electrode line 59b.

Here, the gripper 58 includes one or more slots. In addition, the common electrode 58 is integrally formed with the common electrode line 59, and a component thereof is a metal material capable of forming a mold, and the gripper 58 is formed at both ends of the lamp 51. , 50b) to transmit a high voltage signal applied from an external inverter (not shown) to the lamp 51. The gripper 58 is formed to surround the lamp 51, the slot is formed in the middle to reduce the poor contact with the lamp 51, which may be caused by the processing tolerance than the single plate is formed. In addition, the electrical continuity / conductivity may be improved by maximizing the contact area with the lamp 51.

As such, when the lamp 51 is inserted into the gripper 58, the electrodes 50a and 50b of the lamp 51 directly contact each other, and thus the lamp 51 and the common electrode 53 are structurally soldered without soldering. Electrical connection is possible.

On the other hand, the upper mechanism 70 and the lower mechanism 54 is formed opposite to each other at the end of the lamp 51, that is, the site where the electrodes (50a, 50b) are formed, the side wall mechanism (71) It protrudes from the fixture 70 and is formed in the space between each lamp 51. At this time, the upper mechanism 70 and the side wall mechanism 71 is integrally formed. The direction of the upper and lower mechanisms 70 and 54 is a direction crossing the lamp 51 and passes through an end of the lamp 51 and surrounds the lamp 51 above and below the side wall mechanism 71. .

In addition, a plurality of screws 55, a wire 56 connected to an inverter (not shown), and the first common electrode line 59a are connected to the first common electrode line 59a. It further comprises a circular electrode 57 formed to surround the screw 55 to connect with the connected wire 56. The screw 55 is connected to the common electrode 53, the circular electrode 57 surrounds the screw 55, and since one side of the circular electrode 57 is connected to the wire 56, the common electrode The wires 53 connected to the 53 and the inverter can also be connected without soldering.

In addition, in order to prevent left and right biasing of the lamp 51 when assembling the lamp, a stopper 60 formed on the second common electrode line corresponding to the end of each lamp and a screw may be fastened. It consists of a plurality of holes 61 formed in the portion. Here, the stopper 60 is formed in the longitudinal direction at the end of the second common electrode line 59b.

In addition, reference numerals not described are as follows, the electrode formed on the right side of the lamp 51 is divided into a first electrode 50a, the electrode formed on the left side is a second electrode 50b, the lamp 51 The lower mechanism formed on the right side of the first lower mechanism (54a), the upper mechanism formed on the left side is defined by the second lower mechanism (54b).

On the other hand, the structure of the backlight unit according to an embodiment of the present invention shown in Figure 7 is a structure for fixing the lamp 51 to the gripper 58 after assembling the common electrode line 59 to the lower mechanism 54 After constraining the lamp 51 to the gripper 58, the upper instrument 70 including the sidewall instrument 71 is coupled to the lower instrument 54 including the common electrode line 59.

However, in this case, the common electrode line 59 is formed along the flat lower mechanism 54 so as to have a flat surface, and the sidewall mechanism 71 presses the common electrode line 59, but the flat structure is flat. The side wall mechanism 71 corresponds to a surface, so that the gap between the lamps 51 is wide, and the width of the side wall mechanism 71 is smaller than the gap between the lamps 51, so that the side wall is not restrained. The upper mechanism 70 including the instrument 71 is moved up, down, left and right. In this case, sound noise may occur, and when the upper mechanism 70 is severely moved, noise may be generated due to interference of an electrical signal between components.

Hereinafter, a backlight unit according to another embodiment of the present invention having a structure that solves the above-described constraint problem of the present invention will be described with reference to the drawings.

8 is a cross-sectional side view illustrating a common electrode end of a backlight unit according to another exemplary embodiment of the present invention.

As shown in FIG. 8, the backlight unit according to another embodiment of the present invention forms a protrusion 100 on a portion corresponding to the lamp 90 on the lower mechanism 105, and the protrusion of the convex portion caused by the protrusion 100. The shape is the same as that of the above-described backlight unit of the present invention except that the common electrode line 85 is formed.

In the backlight unit according to another exemplary embodiment of the present invention, due to the convex shape of the protrusion 100, a portion of the upper common electrode line 85 corresponding to the protrusion 100 is raised, and the remaining portion is By being formed on the lower mechanism 105 in a downward shape, the side wall mechanism 81 which protrudes from the upper mechanism 80 at the time of assembly of the instrument corresponds to the lowered portion of the common electrode line 85, Fully restraint may be made between the common electrode line 85 and the sidewall instrument 81. Accordingly, the movement of the upper mechanism 80 including the sidewall mechanism 81 on the common electrode line 85 does not occur, thereby preventing the occurrence of noise, including sound noise, in the mechanism portion at the end of the lamp 90. It becomes possible.

On the other hand, it is observed that the height of the protrusion 100 is about 0.2 to 0.4 mm in the experiment, the most restrictive force between the common electrode line 85 and the side wall mechanism 81 is strengthened. Of course, the size may vary depending on the model of the liquid crystal display device to which the backlight unit is applied. However, when the height of the protrusion 100 exceeds 0.4 mm in experiment, the height of the lamp may be changed, so that the height of the lamp may vary. The connection state may not be good, and when less than 0.2 mm, the constraining effect of the side wall structure due to the uneven shape of the protrusion 100 and the peripheral portion thereof may be deteriorated.

In addition, although not shown in the drawing, a diffusion sheet and a diffusion sheet for scattering the light emitted from the lamp 51 so that a uniform light source distribution is formed on the display surface of the liquid crystal panel on the upper side of the lamp 51. Light scattering means such as a Diffusion plate is further arranged.

As described above, the backlight unit of the present invention further forms a projection on the lower mechanism, thereby convexly forming the common electrode line portion to which the lamp corresponds, due to the shape caused by the projection, and the remaining portion is relatively concave. By doing so, the side wall mechanism supporting the space between the lamps corresponds to the concave portion, thereby reducing the sound noise and the like that can be caused by strengthening the coupling between the parts. Therefore, the backlight unit structure of the present invention can prevent deterioration caused by sound noise.

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit of the invention.

Accordingly, the technical scope of the present invention should not be limited to the contents described in the above embodiments, but should be determined by the claims.

The backlight unit of the present invention as described above has the following effects.

First, the backlight unit of the present invention forms a projection on the upper part of the lower mechanism corresponding to the lamp, and forms a common electrode line along the shape of the convex portion of the projection, thereby between the lamps corresponding to the common electrode line. The seating of the sidewall mechanism may be strengthened to enhance the coupling force between the sidewall mechanism and the common electrode line. Therefore, the sound noise between the parts can be reduced.

Second, a gripper of a gripper type is provided in the common electrode, and the lamp and the common electrode are fixed by inserting the lamp therein, so that the lamp and the common electrode can be electrically connected in a structural configuration without soldering. Accordingly, workability and cost of the backlight unit can be reduced.

Third, the wire connected to the common electrode and the inverter can also be connected without soldering using a screw and a circular electrode. Accordingly, environmentally friendly products can be developed because lead, which is an environmental regulatory substance, is not required.

Fourth, by reducing the noise generated between components through the mechanical shape reinforcement of the supporter side bottom can improve the quality of the backlight unit to increase the user's satisfaction.

Claims (7)

A plurality of lamps arranged at regular intervals with electrodes at both ends outside the tube; A gripper formed to contact and fix the electrode of each lamp for each lamp; Lower mechanisms formed in one direction under both ends of the lamps; An upper mechanism formed on both ends of the lamps to face the lower mechanism; A sidewall mechanism formed on a surface of the upper mechanism and supporting between the lamps in a space between the upper and lower appliances; A protrusion above the lower fixture and positioned below the lamp; And And a common electrode line formed through an upper portion of the lower mechanism including the protrusion. The method of claim 1, The projection is a backlight unit, characterized in that having a height of 0.2 ~ 0.4mm. The method of claim 1, And one or more slots in the gripper. The method of claim 1, The common electrode line may include a first common electrode line formed at an inner end of the lamp and a second common electrode line formed at an outer end of the lamp. The method of claim 1, A plurality of screws for fixing the common electrode line to the lower mechanism; A wire connected to the inverter; And And a circular electrode formed to surround the screw to connect the common electrode line with a wire connected to the inverter. The method of claim 4, wherein A stopper formed on the second common electrode line corresponding to an end of each lamp; And And a plurality of holes formed in a portion to which the screw is fastened. The method according to claim 6, The stopper is a backlight unit, characterized in that formed in the vertical direction at the end of the second common electrode line.

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