KR20070120325A - Lamp and backlight unit and liquid crystal display using the same - Google Patents

Abstract

A lamp, and a backlight unit and an LCD using the same are provided to allow the LCD to have a thin profile by providing a diffuse reflection pattern on a surface of a glass tube charged with a discharge gas. A diffuse reflection pattern is provided on a surface of a glass tube(12) filled with a discharge gas. The diffuse reflection pattern includes an uneven portion(18) protruding from or recessed in a surface of the glass tube. A fine uneven portion is further formed on a surface of the uneven portion. The diffuse reflection pattern is formed on an outer surface or an inner surface of the glass tube. The diffuse reflection pattern is formed by a mechanical or chemical process, or is formed integrally with the glass tube by growing or curing a predetermined material.

Description

LAMP AND BACKLIGHT UNIT AND LIQUID CRYSTAL DISPLAY USING THE SAME}

1 is a perspective view showing a first embodiment of a lamp according to the present invention.

2 to 6 are cross-sectional views and perspective views showing various embodiments of the lamp according to the present invention.

7 is an exploded perspective view showing a second embodiment in which a lamp according to the present invention is applied to a backlight unit.

8 is an enlarged perspective view of the lamp illustrated in FIG. 7.

9 is an exploded perspective view showing a third embodiment in which a lamp according to the present invention is applied to a liquid crystal display.

<Description of the names of the main parts of the drawings>

10 lamp 12 glass tube

14 electrode portion 16 fluorescent layer

18: uneven portion 100: backlight unit

110: lamp unit 130: reflector

140: diffusion plate 150: prism sheet

160: lower chassis 200: liquid crystal display device

210: mold frame 220: liquid crystal display panel

230: upper chassis

The present invention relates to a lamp, a backlight unit and a liquid crystal display using the same, and more particularly, to improve brightness and bright lines of a lamp, which is a light source of the backlight unit, to prevent dark spots, and to form a thin liquid crystal display. A lamp, a backlight unit, and a liquid crystal display using the same.

Recently, flat panel display devices such as liquid crystal displays (LCDs) and plasma display panels (PDPs) are rapidly developing in place of cathode ray tubes (CRTs).

Among such flat panel display devices, the liquid crystal display device does not have self-emission, unlike a plasma display device, and thus requires a light source. Accordingly, the liquid crystal display device may include various light sources according to the screen display method. In general, a direct type is applied to a large screen such as a television, and an edge type is applied to a mobile device such as a mobile phone.

The direct type backlight unit includes a lamp as a light source, a reflector disposed below the lamp, a diffuser plate and a prism sheet disposed above the lamp, and a lower chassis to accommodate the reflector, lamp, diffuser plate, and prism sheet. And the lamp generates light having a line optical distribution as a light source including a cold cathode fluorescent lamp.

In the direct type, the luminance is increased in comparison with the edge type, whereas a bright line in which the shape of the lamp appears on the liquid crystal display panel is generated, and the substantially ring-shaped shape installed in the longitudinal direction of the lamp does not come into contact with the reflector. When the lamp supporter comes into contact with the surface of the lamp, dark spots are generated for a predetermined time, resulting in uneven brightness distribution of the backlight unit.

Therefore, in order to compensate for the uniformity of the brightness of the backlight unit, a diffuser plate causing diffuse reflection is provided at a distance from the lamp. However, since the thickness of the backlight unit is increased by the distance between the diffusion plate and the lamp, it is difficult to maintain the thin structure, which is an advantage of the liquid crystal display.

An object of the present invention is to provide a lamp for preventing the shape of the lamp from appearing on the liquid crystal display panel when the lamp emits light.

In addition, another object of the present invention is to provide a backlight unit which prevents dark spots caused by contact between the lamp and the lamp supporter to make the brightness distribution of the backlight unit uniform.

In addition, the present invention has another object to provide a liquid crystal display device having a thin shape by providing the lamp and the diffusion plate as close as the luminance distribution of the backlight unit is uniform.

In the technical idea of the present invention for achieving the above object, it is achieved by a lamp characterized in that the diffuse reflection pattern is provided on the surface of the glass tube filled with the discharge gas.

Here, the diffuse reflection pattern preferably includes an uneven portion protruded or recessed from the surface of the glass tube.

Moreover, it is preferable to further form fine unevenness | corrugation on the surface of the said uneven | corrugated part.

In addition, the diffuse reflection pattern is preferably provided on the outer surface or the inner surface of the glass tube.

In addition, the diffuse reflection pattern may be formed through mechanical or chemical processing, or by depositing or curing a predetermined material to be integrally formed on the glass tube.

In addition, the diffuse reflection pattern preferably includes a light-transmitting film having an uneven portion formed therein.

In addition, it is preferable to form a fluorescent layer on the glass tube.

On the other hand, according to another technical idea of the present invention for achieving the above object, it is achieved by a backlight unit characterized in that it comprises a lamp having a diffuse reflection pattern on the surface of the glass tube filled with the discharge gas.

Here, it is preferable that a diffuse reflection pattern is provided on an outer surface of the glass tube, and a lamp supporter contacts the diffuse reflection pattern to support the lamp.

On the other hand, another technical idea of the present invention for achieving the above object, the backlight unit including a lamp having a diffuse reflection pattern on the surface of the glass tube filled with the discharge gas, and the light supplied from the backlight unit It is achieved by a liquid crystal display device comprising a liquid crystal display panel for displaying an image by using.

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

First Example

1 is a perspective view showing a first embodiment of a lamp according to the present invention. Referring to the drawings, the lamp 10 is largely composed of a glass tube 12 and the electrode portion 14 formed on both ends of the glass tube. The glass tube 12 has a structure in which a phosphor is coated on an inner surface thereof to form a fluorescent layer 16, and a discharge gas is filled and sealed inside the glass tube 12, and the electrode part 14 includes a glass tube ( A lamp electrode (not shown) provided at both inner ends of the 12 and a lead wire (not shown) electrically connected to the lamp electrode.

The lamp 10 as described above is supplied with power to the lamp electrode through the lead wire from the outside, the electrons of the lamp electrode is excited with the discharge gas in the glass tube to generate ultraviolet light, the ultraviolet light to the glass tube 12 The lamp is converted into visible light while passing through the formed fluorescent layer 16, and a cold cathode fluorescent lamp (CCFL) is generally used.

In particular, the glass tube 12 is provided with a diffuse reflection pattern, the diffuse reflection pattern is projected or recessed from the surface of the glass tube 18 to cause diffuse reflection when visible light irradiated to the outside of the glass tube passes through the glass tube In accordance with the circumference and the length of the glass tube 12 may be formed on the outer surface of the glass tube 12 or formed on the inner surface or formed on the outer and inner surfaces.

These diffuse reflection patterns are cylindrical, conical, elliptical, elliptical, polygonal, polygonal, truncated cone, truncated ellipsoidal, truncated polygonal, spherical, hemispherical, ellipsoidal, and elliptic hemispheres. It may be formed in various shapes such as shape, polyhedron shape and half-polyhedron shape.

In addition, the uneven portion 18 may be formed by a straight line, an oblique line, a curve, a grating, or a combination thereof having a constant or irregular interval.

When the diffuse reflection pattern is provided in the glass tube 12 as described above, when the visible light passing through the fluorescent layer 16 formed on the glass tube 12 passes through the glass tube 12, the uneven portion formed on the surface of the glass tube 12 ( 18) visible light strikes and scatters in various directions, resulting in a uniform luminance distribution compared to a glass tube having a conventional smooth surface.

The diffuse reflection pattern provided in the glass tube as described above can be implemented in various ways will be described based on FIGS. 2 to 6. FIG. 2 further shows fine concavo-convex on the surface of the concave-convex portion formed on the outer surface of the glass tube, that is, the projection 28b is formed on the surface of the glass tube 12 but the minute projection 28a on the surface of the projection 28b. Is further formed. Accordingly, the visible light passing through the fluorescent layer 16 is refracted by the projections 28b, and the refracted visible light is refracted once again by the fine projections 28a, resulting in uniform luminance distribution.

In addition, the diffuse reflection pattern may be a groove 38 formed on the outer surface of the glass tube 12 and the fluorescent layer 16 is formed on the inner surface of the glass tube 12, as shown in FIG. As shown in FIG. 4, the projections 48 may be formed on the inner surface of the glass tube 12 without changing the external volume of the glass tube 12, and the fluorescent layer 16 may be formed on the surface of the protrusions 48. As described above, the fluorescent layer 16 may be formed on the inner surface of the glass tube, and the bead 58 of the light transmissive material may be attached to the outer surface of the glass tube 12.

In some cases, the groove 38 formed on the outer surface of the glass tube 12 described above, the projection 48 formed on the inner surface of the glass tube 12, and the bead 58 of the light transmissive material may be implemented in combination. have. In addition, fine grooves and protrusions are formed on the grooves 38, the protrusions 48, and the beads 58. The diffuse reflection pattern may be formed by mechanical or chemical processing on the surface of the glass tube 12 or deposit a predetermined material. Or may be formed by curing.

In addition, the diffuse reflection pattern may be formed in a predetermined thin film form and then bonded to the glass tube, thereby forming a fluorescent layer 16 by coating a phosphor on an inner surface of the glass tube 12 as shown in FIG. 6. The projection 68b is formed on a plane of the translucent film 68a surrounding the outer surface of the glass tube 12 so that an adhesive is applied to the rear surface of the translucent film 68a to be fixed to the outer surface of the glass tube 12. have. In some cases, a fluorescent layer may be positioned between the translucent film 68a and the outer surface of the glass tube 12.

2nd Example

FIG. 7 is an exploded perspective view showing a second embodiment in which a lamp according to the present invention is applied to a backlight unit, and FIG. 8 is an enlarged perspective view of the lamp shown in FIG. 7. In the following description, a description overlapping with the above-described first embodiment will be omitted.

Referring to the drawings, the backlight unit 100 includes a lamp unit 110 for generating light, a reflector 130 disposed under the lamp unit 110, and the lamp unit 110. The diffuser plate 140 and the prism sheet 150 disposed on the upper portion, and the lower chassis 160 for accommodating the lamp unit 110, the reflector plate 130, the diffuser plate 140, and the prism sheet 150. do.

The lamp unit 110 includes a plurality of lamps 10 arranged in parallel, a plurality of lamp fixing units 20 for fixing the lamps 10, and the plurality of lamp fixing units 20. Lamp support 30 is included. The lamp 10 generates light by a driving voltage applied from the outside, and each of the lamps 10 includes a discharge gas included in the glass tube 12 and the glass tube 12, and both ends of the glass tube 12. It consists of an electrode part 14 provided in the.

In this case, the glass tube 12 is provided with a diffuse reflection pattern, and is excited with the discharge gas in the glass tube 12 by the driving voltage applied from the outside of the lamp 10 to generate ultraviolet light. In addition, the ultraviolet light is converted into visible light while passing through the fluorescent layer 16 formed on the glass tube 12, and the converted visible light is scattered in various directions by the diffuse reflection pattern when passing through the glass tube 12. Resulting in a uniform luminance distribution.

In addition, the glass tube 12 is provided with a plurality of lamp supporters 40 in the longitudinal direction of the glass tube 12 so as to be spaced apart from the glass tube 12 and the reflecting plate 130 in direct contact with each other. By providing a diffuse reflection pattern on the outer surface, the area in which the lamp supporter 40 and the glass tube 12 contact each other is minimized.

That is, the diffuse reflection pattern is formed to protrude or recess from the outer surface of the glass tube 12, and the annular lamp supporter 40 is seated on the diffuse reflection pattern protruded or recessed from the outer surface of the glass tube 12, The contact area between the glass tube 12 and the lamp supporter 40 is minimized. Accordingly, the contact area between the lamp supporter 40 and the glass tube 12 is reduced by the shape of the diffuse reflection pattern, so that the heat of the glass tube 12 is lost to the lamp supporter 40 to improve dark spots for a certain time.

Each of the lamp fixing parts 20 includes a base substrate (not shown) on which one end of the lamp 10 is seated, and a fixing clip and a fixing protrusion (not shown) for protruding from the base substrate to fix the lamp 10. The lamp support part 30 includes a bottom surface 32 on which the plurality of lamp fixing parts 20 are mounted, and a side wall 34 extending vertically from the bottom surface 32. In this case, the lamp fixing part 20 may be formed of a conductive material to apply power to the electrode part 14 of the lamp 10. In this case, the lamp support 30 must be formed of an insulating material to electrically insulate the electrode 14 and the lower chassis 160 of the lamp 10.

The reflective plate 130 reflects the light incident from the lamp 10, which is the light source, to the light emitting surface of the backlight to increase light utilization efficiency, and to lower the lamp unit 110 so that the entire light emitting surface has a uniform luminance distribution. It is located at. The reflective plate 130 generally uses a polyester film, and has a structure in which a reflective layer and a packing layer are coated on both sides of the polyester film to prevent incident light from leaking out, and to improve luminance characteristics with a high reflection layer structure having excellent concealability. The reflective plate 130 may be attached to the lower chassis 160 by an adhesive, a double-sided adhesive tape, or the like. Furthermore, the reflector plate 130 may be integrally formed with the lower chassis 160.

The diffusion plate 140 directs the light incident from the lamp 10 to the front, and diffuses and irradiates the light to have a uniform distribution in a wide range. As the diffusion plate 140, it is preferable to use a film made of a transparent resin coated with a predetermined light diffusion member on both surfaces.

The prism sheet 150 serves to change the light incident from the diffuser plate 140 to be vertically emitted from the light incident from the diffuser plate 140 to vertically convert the light emitted from the diffuser plate 140. At least one prism sheet 150 may be disposed on the diffusion plate 140.

The lower chassis 160 serves to surround and protect the side and bottom surfaces of the lamp unit 110. The lower chassis 160 is formed in a box shape of an open rectangular parallelepiped, and a storage space having a predetermined depth is formed therein. Here, a lamp driving circuit board 170 for driving the lamp 10 is installed below the lower chassis 160. The lamp driving circuit board 170 generates a plurality of driving voltages to generate driving voltages. It includes a portion (not shown). The driving voltage generation unit may include at least one inverter for boosting an AC voltage having a low voltage applied from the outside to an AC voltage having a high voltage for driving the lamp 10. The driving voltage generation unit and the lamp 10 may be electrically connected. Is connected.

When the diffuse reflection pattern is provided in the glass tube 12 as described above, it is possible to prevent the bright lines appearing in the shape of the lamp on the diffusion plate 140 and the prism sheet 150 when the lamp 10 emits light.

3rd Example

9 is an exploded perspective view of a liquid crystal display showing a state in which a lamp according to the present invention is applied. In the following description, overlapping descriptions of the above-described first and second embodiments will be omitted.

Referring to the drawings, the liquid crystal display 200 includes a backlight unit 100 having a diffuse reflection pattern on a lamp 10, a mold frame 210 for accommodating the backlight unit 100, and a liquid crystal display. An upper chassis 230 is formed to surround a predetermined area and a side portion of the display panel 220 and the backlight unit 100.

The liquid crystal display panel 220 includes a thin film transistor substrate 222, a data side and gate side tape carrier package (TCP) 224a and 224b connected to the thin film transistor substrate 222, and data. Data side and gate side printed circuit boards 226a and 226b connected to the side and gate side tape carrier packages 224a and 224b, the color filter substrate 228 corresponding to the thin film transistor substrate 222, and the thin film transistor. And a liquid crystal layer (not shown) injected between the substrate 222 and the color filter substrate 228. In addition, the display device may further include a polarizer (not shown) corresponding to the upper portion of the color filter substrate 228 and the lower portion of the thin film transistor substrate 222.

Here, the color filter substrate 228 is a substrate in which RGB pixels, which are color pixels in which a predetermined color is expressed while light passes, are formed by a thin film process. A common electrode (not shown) made of a transparent conductor such as indium tin oxide (ITO) or indium zinc oxide (IZO), which is a transparent conductive thin film, is formed on the front surface of the color filter substrate 228. .

The thin film transistor substrate 222 is a transparent glass substrate in which a thin film transistor (TFT) and a pixel electrode are formed in a matrix form. The data line is connected to the source terminal of the thin film transistors, and the gate line is connected to the gate terminal. In addition, a pixel electrode (not shown) made of a transparent electrode made of a transparent conductive material is connected to the drain terminal. When an electrical signal is input to the data line and the gate line, each thin film transistor is turned on or turned off to apply an electrical signal necessary for pixel formation to a drain terminal.

That is, when the power is applied to the gate terminal and the source terminal of the thin film transistor substrate 222 as described above and the thin film transistor is turned on, an electric field is formed between the pixel electrode and the cavity electrode of the color filter substrate 228. Due to this electric field, the arrangement of the liquid crystal injected between the thin film transistor substrate 222 and the color filter substrate 228 is changed, and the light transmittance is changed according to the changed arrangement to obtain a desired image.

The data side and gate side tape carrier packages 224a and 224b are respectively connected to data lines and gate lines of the thin film transistor substrate 222 to apply a data driving signal and a gate driving signal to the thin film transistor. In this case, an integrated circuit (IC) may be mounted in the data side and gate side tape carrier packages 224a and 224b. The data side and gate side printed circuit boards 226a and 226b are connected to the data side and gate side tape carrier packages 224a and 224b to apply external image signals and gate driving signals.

The backlight unit 100 may include a lamp unit 110 that generates light, a reflector plate 130 disposed below the lamp unit 110, a diffuser plate 140 disposed above the lamp unit 110, and A lower chassis 160 for accommodating the prism sheet 150, the reflector plate 130, the lamp unit 110, the diffusion plate 140, and the prism sheet 150, and for driving the lamp 10. The lamp driving circuit board 170 is included.

The mold frame 210 is formed in a rectangular frame shape and includes a planar portion 212 and sidewall portions 216 bent at right angles therefrom. The mounting part 214 may be formed on the flat part 212 so that the liquid crystal display panel 220 may be mounted. The seating part 214 may use a fixing protrusion for contacting each of the edge side surfaces of the liquid crystal display panel 220 and aligning them, or may be formed using a predetermined stepped step surface. In addition, a lamp unit 110, a reflector plate 130, a diffusion plate 140, and a prism sheet 150 may be disposed between the mold frame 210 and the lower chassis 160.

The upper chassis 230 is configured in the form of a rectangular window frame having a flat portion and sidewall portions bent at right angles therefrom. The planar portion of the upper chassis 230 supports a portion of an edge of the liquid crystal display panel 220 at a lower portion thereof, and the sidewall portion is coupled to face the sidewalls of the lower chassis 160.

In particular, the lamp unit 110 includes a plurality of lamps 10 having a diffuse reflection pattern, a plurality of lamp fixing units 20 for fixing the lamps 10, and a plurality of lamp fixing units 20. The lamp support unit 30 is accommodated, the diffuse reflection pattern is provided in the lamp, the lamp unit 110 and the diffusion plate 140 to have a uniform luminance distribution compared to the glass tube having a conventional smooth surface. Can be installed closer.

For example, the lamp support 30 may include a bottom surface 32 on which a plurality of lamp fixing parts 20 are mounted, and a side wall 34 extending vertically from the bottom surface 32. If the diffusion plate 140 is fixedly installed, and the height of the side wall 34 is a separation distance for maintaining the distance between the lamp 10 and the diffusion plate 140, the lamp 10 by the diffuse reflection pattern ), The height of the sidewalls 34 of the lamp support part 30 is made low as the luminance distribution of the light emitting device becomes uniform, so that the distance between the lamp 10 and the diffuser plate 140 can be set closer.

That is, as shown in the drawing, if the height of the sidewall 34 for maintaining the distance between the lamp and the diffuser plate having a conventional uniform luminance distribution is A, the lamp 10 provided with the diffuse reflection pattern As a result, the height of the sidewalls 34 of the fixed support part 30 may be as low as B.

In addition, the mold frame 210 and the lower chassis 160 are matched, and the lamp unit 110, the reflecting plate 130, the diffusion plate 140, and the prism are disposed between the mold frame 210 and the lower chassis 160. If the seat 150 is fixedly installed, the height of the side wall portion 216 bent at right angles in the planar portion 212 of the mold frame may be lowered by the distance between the lamp 10 and the diffusion plate 140. It is possible to form a thin liquid crystal display device.

On the other hand, the present invention is not limited only to the above-described embodiment, but can be modified and modified within the scope not departing from the gist of the present invention, it should be seen that such modifications and variations are included in the technical idea of the present invention. do.

For example, in the above-described embodiment, the fluorescent layer is formed on the glass tube of the lamp. Alternatively, the fluorescent layer may be formed on any one of several optical sheets disposed outside the lamp.

The lamp according to the present invention, the backlight unit and the liquid crystal display using the same have a diffuse reflection pattern in the glass tube of the lamp, and thus have a uniform luminance distribution compared to a glass tube having a conventional smooth surface, so that when the lamp emits light, There is an effect that can prevent the bright line appearing.

In addition, since the lamp with the diffuse reflection pattern is applied to the backlight unit, the contact area between the lamp supporter and the glass tube of the lamp is minimized to prevent dark spots.

In addition, as the luminance distribution of the backlight unit becomes uniform, the lamp unit and the diffusion plate may be installed closer to each other, thereby achieving a thinner LCD.

Claims (10)

The lamp characterized in that the diffuse reflection pattern is provided on the surface of the glass tube filled with the discharge gas. The lamp of claim 1, wherein the diffuse reflection pattern includes an uneven portion protruding or recessed from the surface of the glass tube. The lamp according to claim 2, further comprising fine concavo-convex on the surface of the concave-convex portion. The lamp of claim 1, wherein the diffuse reflection pattern is formed on an outer surface or an inner surface of the glass tube. The lamp of claim 1, wherein the diffuse reflection pattern is formed by mechanical or chemical processing or by depositing or curing a predetermined material to be integrally formed with a glass tube. The lamp of claim 1, wherein the diffuse reflection pattern comprises a light transmissive film having uneven portions. The lamp according to claim 1, wherein a fluorescent layer is formed on the glass tube. And a lamp having a diffuse reflection pattern on the surface of the glass tube filled with the discharge gas. The backlight unit of claim 8, wherein a diffuse reflection pattern is provided on an outer surface of the glass tube, and a lamp supporter contacts the diffuse reflection pattern to support the lamp. A backlight unit including a lamp having a diffuse reflection pattern on a surface of the glass tube filled with discharge gas; And a liquid crystal display panel which displays an image by using the light supplied from the backlight unit.

Images