KR20040024885A - Direct type flat light - Google Patents

Abstract

PURPOSE: A direct light emitting flat light source is provided to achieve improved optical characteristics, while preventing a leakage of current from the lead wire. CONSTITUTION: A direct light emitting flat light source comprises a lamp assembly(20) including lamps(10) and a conductive plate(25) connected to a lead wire(40) connected to a power supply so as to supply an electrical energy to the lamps; a fixing member(70) arranged in parallel with the lamps, in the vicinity of the end of the conductive plate, wherein the fixing member has a reflective surface(71) for reflecting the light emitted from the lamps and a lead wire accommodating groove for accommodating the lead wire; a diffusion plate(50) arranged in the vicinity of the lamp assembly such that the diffusion plate diffuses the light emitted from the lamps; and a frame for accommodating the lamp assembly, fixing member and the diffusion plate, wherein the frame has a window(63) arranged at the surface of the frame contacting the diffusion plate. The lead wire accommodating groove has a lead wire guide for separating the lead wire from the frame and supporting the lead wire.

Description

Direct type flat light

The present invention relates to a direct light emitting flat light source, and more particularly, to a direct light emitting flat light source having lamps having improved optical properties by improving the arrangement of lead wires electrically connected to the electrodes of the lamp.

The flat light source is used as a back light for illuminating the back of a flat panel display such as an LCD, a light panel used for a billboard, a medical diagnosis, or the like. Light source of an X-ray film reader. Hereinafter, the flat panel display will be described.

In general, flat panel displays are classified into light emitting and light receiving types, and the light emitting types include cathode ray tubes, electroluminescent (EL) devices, plasma display panels (PDPs), and the like. Liquid Crystal Display (LCD) and the like. Since the liquid crystal display itself is a light-receiving element which emits light and does not form an image, but receives light from the outside to form an image, a separate light source, for example, a backlight, allows the image to be observed even in a dark place.

The backlight for the liquid crystal display is a direct type for directing the light emitted from the plurality of fluorescent lamps directly below the liquid crystal panel according to the installation form of the lamp, which is a light emitting element, and the liquid crystal panel, and the side of the liquid crystal panel. Light emitted by a fluorescent lamp is classified into an edge type that is transmitted to a liquid crystal panel through a light guide plate that changes its traveling direction vertically. However, the edge emission type is a method of irradiating light only on one side of the liquid crystal panel, and thus there is a disadvantage in that sufficient and uniform luminance cannot be obtained in a large screen, and thus, there is a tendency for an increase in demand for a direct emission type light source.

Lamps, which are light sources in direct-emitting flat light sources, are generally coated with fluorescent materials on their inner surfaces, filled with discharge gases such as argon and mercury inside the lamps, and electrodes having voltage applied to both ends of the lamp. to be. The lamp has a Cold Cathode Fluorescent Lamp (CCFL) in which electrodes at both ends are installed in a tube, and an External Electrode Fluorescent lamp in which electrodes at both ends are provided on an outer surface of the tube, depending on the shape of the electrode. Lamp; EEFL). However, the cold-cathode fluorescent lamps have a problem in that only one lamp emits light and other lamps do not emit light when AC power is applied by connecting them in parallel as one electrode, and power is separately supplied for each fluorescent lamp. Even when all the lamps are connected to emit light, there is a problem in that the electrode is easily deteriorated by direct contact with the emitting gas and thus has a short lifespan. Therefore, a direct light emitting type planar light source using an external electrode without the above problems is in the spotlight.

Referring to FIG. 1, several lamps 1 are installed in the lower frame 6 in electrical connection with a conductive plate (not shown) disposed in the upper lamp holder 2 and the lower lamp holder 3. have. The conductive plate is connected to a power source via a lead wire 4 via a connector 8 and an inverter 9. Meanwhile, the reflector 5 installed between the lamps 1 and the bottom surface of the lower frame 6 reflects the light so that the light from the lamp travels toward the liquid crystal panel through a window formed in the upper frame (not shown). A diffusion plate (not shown) is installed between the upper frame and the lamps to diffuse light emitted from the lamps. In addition, fixing members 7 are installed at two sides of the lower frame 6 in which the lamp holders 2 and 3 are not installed to reflect light to the liquid crystal panel through the window along with the reflecting plate. .

In the conventional planar light source, the lead wire 4 connected to the external power source is exposed to the lower frame 6 of the metal material on which the lamp 1 is disposed, without being shielded and fixed by separate shielding means or fixing means. . Therefore, the current flowing through the lead wire 4 is interfered by the electromagnetic waves of the adjacent lamp 1 or other electronic devices, so that the current becomes unstable, such as noise generated in the current supplied to the lamp 1, There is a problem that adversely affect the optical characteristics, for example, the brightness of the light or the uniformity of the color.

In addition, the lead wire 4 is located close to the lower frame, there is a problem that the current flowing through the lead wire leaks.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-described problems, and an object thereof is to provide a direct light emitting flat light source having a lamp having improved optical characteristics by blocking lead wires from external electromagnetic waves to stabilize the current supplied to the lamp. It is done.

In addition, an object of the present invention is to provide a direct light emitting planar light source in which current does not leak from a lead wire.

1 is a perspective view showing a conventional direct emission type plane light source,

2 is an exploded perspective view showing a direct emitting flat light source according to the first embodiment of the present invention;

3 is a perspective view showing a state in which the lamps of the direct emission type flat light source according to the first embodiment of the present invention are mounted on the lower frame,

4 is an enlarged partial perspective view of part A of FIG. 3,

FIG. 5 is a partially enlarged perspective view of the direct emission type planar light source according to the second embodiment of the present invention.

The present invention to achieve the above object,

A lamp assembly having lamps and a conductive plate connected to a lead wire connected to a power supply to supply electricity to the electrodes of the lamps;

A fixing member disposed adjacent to the end of the conductive plate in parallel with the lamp and having a reflective surface reflecting light from the lamp along a longitudinal direction and a lead bow groove for receiving the lead wire;

A diffuser plate disposed adjacent to one surface of the lamp assembly and configured to diffuse light emitted from the lamps; And

A direct light emitting type planar light source comprising: a lamp assembly, a fixing member, and a diffuser plate, and a frame having a window formed on a surface in contact with the diffuser plate.

In the lead wire receiving groove of the fixing member, a direct light emitting type light source having a lead wire guide part for supporting the lead wire spaced from the frame is provided.

The lead wire guide parts may be formed in the inner surface of the fixing member at a predetermined interval, and each lead wire guide portion may have a shape protruding from the inner surface of the fixing member.

The lead wire guide part may be formed on an inner surface of the fixing member, and may have a shape extending in the longitudinal direction of the fixing member.

In addition, the present invention to achieve the above object,

A lamp assembly having lamps and a conductive plate connected to a lead wire connected to a power supply to supply electricity to the electrodes of the lamps;

It is disposed adjacent to the end of the conductive plate in parallel with the lamp, and provided with a reflective surface for reflecting light from the lamp along the longitudinal direction and a lead bow groove for receiving the lead wire, the conductive layer on the inner or outer surface A fixed member formed;

A diffuser plate disposed adjacent to one surface of the lamp assembly and configured to diffuse light emitted from the lamps; And

The lamp assembly, the fixing member, and the diffusion plate is accommodated, and provides a direct light emitting type light source having a; frame formed with a window on the surface in contact with the diffusion plate.

The lamp assembly accommodates the conductive plate therein and defines an upper lamp holder and a lower lamp holder defining a lamp insertion hole into which the electrode of the lamp can be inserted, and is installed on the upper lamp holder to reflect light toward the lamp holder. The lamp holder cover is further provided, and the fixing member and the lamp holder cover are preferably integrally formed.

Preferably, the upper lamp holder and the lamp holder cover are integrally formed.

The reflective surface is preferably inclined downward toward the center of the lower frame.

The direct light emitting type flat light source further includes a lamp support member made of an elastic material, and the fixing member further includes a lamp support member groove accommodating an end portion of the lamp support member.

Hereinafter, a first embodiment of the present invention will be described in detail with reference to the accompanying drawings. FIG. 2 is an exploded perspective view showing a direct light emitting light source according to the present invention, and FIG. 3 is a perspective view showing a state in which the remaining parts excluding the upper frame 62 and the diffusion plate 29 are assembled. Is shown.

The direct emission type flat light source illustrated in FIG. 2 includes: an upper lamp holder 21, a lower lamp holder 22, and a lamp 10 in which electrodes are inserted into lamp insertion holes formed between the lamp holders 21 and 22. For example, a conductive plate 25 is disposed between the lamp holders 21 and 22 to supply power to the lamps 10, and light is installed on the upper lamp holder 21 toward the lamp holder. A lamp assembly 20 having a reflecting lampholder cover 28; A reflector 50 disposed below the lamp assembly 20; A diffusion plate 29 disposed above the lamp assembly 20; A fixing member 70 disposed in parallel with the lamp and having a reflecting surface 71 reflecting light; A lamp support member (75) for supporting the lamps from below; A lead wire 40 and a connector 80 connecting the conductive plate 25 and an external power source; A lower frame 61 accommodating the lamp assembly 20, the reflecting plate 50, the diffusion plate 29, the fixing member 70, and the lamp support member 75 therein; And an upper frame 62 having a window 63 through which the light passing through the diffusion plate 29 is emitted to the outside and coupled to the lower frame 61.

The lamp assembly 20 includes lamps 10, an upper lampholder 21, a lower lampholder 22, a conductive plate 25, and a lampholder cover 28. The lamp may be a cold cathode fluorescent lamp (CCFL), but in this embodiment, the lamp is an external electrode fluorescent lamp (EEFL). The upper lamp holder 21 and the lower lamp holder 22 is preferably formed of an elastic material such as rubber to support the lamp 10 more elastically, and the upper lamp holder 21 and the lower lamp holder. A lamp insertion hole is formed at the boundary where the 22 is coupled, and the electrodes of the lamp 10 are inserted into the lamp insertion hole 22 to be electrically connected to the conductive plate 25. The conductive plate 25 functions to connect the lamps with an external power source. The lampholder cover 28 has a color that facilitates the reflection of light so that the outer surface of the lampholder cover 28 allows the large amount of light emitted from the lamp to travel outside through the window 63 as well as the lampholder. It is also possible to function to fix the fields 21 and 22. Meanwhile, as shown in FIG. 2, the upper lamp holder 21 may be formed separately from the lamp holder cover 28, but they may be formed integrally. There is an advantage that this can be reduced.

The reflecting plate 50 disposed below the lamp assembly 20 has a color (for example, white) having a characteristic that a surface in contact with the lamp assembly 20 reflects light. However, when the color of the inner surface of the lower frame 61 reflects the light is good, the reflecting plate is not necessarily required, and by applying a white color on the inner surface of the lower frame 61 may have the same function as the reflecting plate. have.

The diffusion plate 29 disposed on the upper side of the lamp assembly 20 serves to diffuse the light emitted from the lamp 10, which is not installed on the front surface of the planar light source, but at regular intervals. It is due to the installation. Since the light is directed to the window through the diffuser plate 29, only the part where the lamp 10 is located is bright and the part that is not the lamp 10 is not dark but the overall uniform light is emitted to the outside through the window 63.

The fixing member 70 disposed in parallel with the lamp adjacent to the end of the conductive plate has a reflecting surface 71 inclined downward toward the center of the lower frame 61 along its longitudinal direction. And a lead bow groove 72 indented upward. It is preferable that the reflective surface 71 has a color (for example, white) advantageous for the reflection of light.

The configuration of the fixing member 70 is shown in more detail in FIG. FIG. 4 is an enlarged perspective view of portion A of FIG. 3, in which the lamp holder cover 28 and the upper lamp holder 21 are omitted. As shown, the fixing member 70 has a lead bow groove 72 recessed upward in the lower part, and the lead wire 40 is accommodated in the lead bow groove. The fixing member is formed of a non-conductive material such as plastic, and the conductive layer 74 is formed on the outer surface 70a or the inner surface 70b as shown in FIG. 4. The conductive layer may be formed by, for example, a sheet formed of a metal such as copper attached to the outer surface 70a or the inner surface 70b, or a paste formed of silver (Ag) applied to the inner surface of the lead bow groove. It is formed by the method of, and serves as an electromagnetic shielding to prevent external electromagnetic waves from affecting the lead wire (40). Due to the electric vehicle shielding function of the conductive layer, the current supplied to the lamp is stabilized, and thus the brightness and the uniformity of color emitted by the lamp are improved.

Preferably, the fixing member further includes a lead wire guide part 70c for supporting the lead wire away from the lower frame, which separates the lead wire 40 from the lower frame so that the current flowing through the lead wire is lower than the lower frame. It serves to prevent leakage to (61). The lead wire guide part 70c of the present embodiment is disposed on the inner surface of the fixing member 70 at regular intervals rather than continuously formed along the longitudinal direction thereof, and is formed in a shape protruding from the inner surface of the fixing member. This is to facilitate the formation of the conductive layer 74 on the inner surface 70b of the fixing member. Even if the lead wire guide portions 70c are arranged at regular intervals, the lead wires can be prevented from sagging between the lead wire guide portions 70c by adjusting the length of the lead wires. Applicants' experiments show that when the planar light source is actually applied to a TFT-LCD of 14 inches or more, it is preferable that the lead wire 40 maintain a spacing of 4 mm or more from the lower frame 61. In this case, Preferably, the lead wire guide part 70c is formed to support the lead wire at a distance of 4 mm or more from the lower frame.

Meanwhile, as shown in FIG. 2, the fixing member and the lamp holder cover may be formed separately, but they may be formed integrally. When the fixing member and the lamp holder cover are integrally formed, the components accommodated in the frame are further included. The advantage is that it can be reliably supported.

The lamp support member 75 is formed of an elastic material and stably supports the lamps. The lamp support member is preferably formed with a lamp receiving groove 76 that can be fixed to receive the lamps. On the other hand, it is more preferable that the fixing member further comprises a lamp support member groove 73 to fix both ends of the lamp support member 75.

The lead wire 40 connected to the conductive plate 25 is accommodated in the lead bow groove 72 of the fixing member 70 and connected to the connector 80. Although the lead wire is illustrated as being connected to the power source via the inverter 90 by the connector 80, the inverter 90 may not exist depending on the type of power source.

The lower frame 61 accommodates the lamp assembly 20, the reflecting plate 50, the diffusion plate 29, the fixing member 70, and the lamp support member 75 therein. The upper frame 63 includes a window 63 that allows light passing through the diffusion plate 29 to be emitted to the outside, and is coupled to the lower frame 61 to provide an internal lamp assembly 20. , The reflecting plate 50 and the diffusion plate 29 are housed therein.

The lower frame and the upper frame are generally formed of a conductive member such as a metal plate, which serves as an electromagnetic shielding to prevent external electromagnetic waves from affecting the lead wire 40 together with the conductive layer 74. .

Although FIG. 2 illustrates that the upper frame 62 and the lower frame 61 constitute the entire frame for accommodating the lamp assembly 20, the reflecting plate 50, the diffusion plate 29, and the like, the lamp assembly is disposed at one side. The frame body having an opening into which the 20, the reflecting plate 50, the diffusion plate 29, and the like can be inserted, and the frame configured as a frame cover to close the opening, are also within the scope of the present invention.

5 shows a part of the direct light emitting type planar light source according to the second embodiment of the present invention. The present embodiment will be described centering on matters different from the first embodiment. The present embodiment is different from the first embodiment in that the lead wire guide portion 70d is elongated in the longitudinal direction of the fixing member on the inner surface of the fixing member 70. Since the lead wire guide part 70d is formed in this manner, the connection strength between the lead wire guide part and the inner surface 70b of the fixing member 70 is enhanced. In this case, however, it may be difficult to form a conductive layer on the inner surface of the fixing member 70, which may be solved by forming the conductive layer on the outer surface 70a of the fixing member. At this time, it is preferable that the conductive layer is formed of a material having a good light reflectance, or a paint having a good light reflectance is applied to the surface of the conductive layer.

In this embodiment, in particular, when the lower frame is formed of a non-conductive material, electromagnetic waves may affect the lead wires through the lower frame side of the lead wires. The influence of the electromagnetic waves on the lead wires is illustrated in FIG. 5. It can be blocked by forming a conductive layer (not shown) on the horizontal plane of the lead wire guide portion 70d.

Although the present invention has been described with reference to the embodiments illustrated in the drawings, this is merely exemplary, and it will be understood by those skilled in the art that various modifications and equivalent other embodiments are possible. Therefore, the true technical protection scope of the present invention will be defined by the technical spirit of the appended claims.

The present invention provides a direct light emitting type flat light source having a lamp having improved optical characteristics by blocking lead wires from external electromagnetic waves to stabilize the current supplied to the lamp.

In addition, the present invention provides a direct light emitting type planar light source in which current does not leak from a lead wire.

Claims (8)

A lamp assembly having lamps and a conductive plate connected to a lead wire connected to a power supply to supply electricity to the electrodes of the lamps; A fixing member disposed adjacent to an end of the conductive plate in parallel with the lamp and having a reflective surface reflecting light from the lamp along a longitudinal direction and a lead bow groove for receiving the lead wire; A diffuser plate disposed adjacent to one surface of the lamp assembly and configured to diffuse light emitted from the lamps; And A direct light emitting type planar light source comprising: a lamp assembly, a fixing member, and a diffuser plate, and a frame having a window formed on a surface in contact with the diffuser plate. A direct light emitting type light source having a lead wire guide portion in the lead wire receiving groove of the fixing member, the lead wire being separated from the frame to support the lead wire. The method of claim 1, The lead wire guide portion is formed on the inner surface of the fixing member several times, each of the lead wire guide portion is a direct light emitting type light source, characterized in that it has a shape protruding from the inner surface of the fixing member. The method of claim 1, The lead wire guide portion is formed on the inner surface of the fixing member, the direct light emitting type flat light source, characterized in that it has a shape extending in the longitudinal direction of the fixing member. A lamp assembly having lamps and a conductive plate connected to a lead wire connected to a power supply to supply electricity to the electrodes of the lamps; It is disposed adjacent to the end of the conductive plate in parallel with the lamp, and has a reflective surface reflecting light from the lamp along the longitudinal direction and a lead bow groove for receiving the lead wire, the conductive layer on the inner or outer surface A fixed member formed; A diffuser plate disposed adjacent to one surface of the lamp assembly and configured to diffuse light emitted from the lamps; And And a lamp assembly, a fixing member, and a diffuser plate, and a frame having a window formed on a surface in contact with the diffuser plate. The method according to any one of claims 1 to 4, The lamp assembly accommodates the conductive plate therein and defines an upper lamp holder and a lower lamp holder defining a lamp insertion hole into which the electrode of the lamp can be inserted, and is installed on the upper lamp holder to reflect light toward the lamp holder. The lamp holder cover is further provided, The fixing member and the lamp holder cover is a direct light emitting type light source, characterized in that formed integrally. The method of claim 5, wherein The top lamp holder and the lamp holder cover is a direct light emitting type light source, characterized in that formed integrally. The method according to any one of claims 1 to 4, The reflecting surface is a planar light source, characterized in that inclined downward toward the center of the lower frame. The method according to any one of claims 1 to 4, The direct light emitting type flat light source further includes a lamp support member made of an elastic material, and the fixing member further includes a lamp support member groove accommodating an end portion of the lamp support member.