CN100514153C - Backlight assembly - Google Patents

Abstract

An array substrate has a first pixel unit and a second pixel unit adjacent to the first pixel unit. The first pixel unit has a first reflection area for reflecting a first light and a first transmission area for transmitting a second light, and the second pixel unit has a second reflection area for reflecting the first light and a second transmission area for transmitting the second light, wherein the second reflection area has a size different from that of the first reflection area, and the second transmission area has a size different from that of the first transmission area. The size ratio between the first reflection area and the first transmission area is different from the size ratio between the second reflection area and the second transmission area. Therefore, flickering due to an inverse driving method can be reduced.

Description

Backlight component

technical field

The present invention relates to a light-emitting element, and in particular to a backlight assembly, which can effectively reduce power consumption and has high safety.

Background technique

The multimedia technology in today's society is quite developed, most of which benefit from the progress of semiconductor elements or display devices. As far as displays are concerned, liquid crystal displays (Liquid crystal displays) with superior characteristics such as high image quality, good space utilization efficiency, low power consumption, and no radiation have gradually become the mainstream of the market. Since the liquid crystal display panel does not have the function of emitting light, a backlight assembly must be arranged under the liquid crystal display panel to provide a side light source so that the liquid crystal display panel can achieve the purpose of displaying.

FIG. 1 is a schematic cross-sectional view of a conventional liquid crystal display. Please refer to FIG. 1 , the conventional liquid crystal display 100 includes a liquid crystal display panel 110 , a backlight assembly 120 and an inverter circuit board 130 . Wherein, the liquid crystal display panel 110 is arranged above the backlight assembly 120, and the backlight assembly 120 can provide the surface light source required for the liquid crystal display panel 110 to display images, and the converter 130 is arranged beside the backlight assembly 120, which is suitable for converting direct current AC power required to drive the backlight assembly 120 .

Specifically, the backlight assembly 120 includes several cold cathode fluorescent lamps 122 (Cold Cathode Fluorescent Lamp, CCFL), a frame 124 and a diffusion plate (Diffusion Plate) 126, and the cold cathode fluorescent lamps 122 are disposed in the frame 124. In addition, the diffusion plate 126 is disposed on the frame 124 and located above the CCFL tubes 122 .

The above-mentioned frame 124 is composed of a plurality of side plates 124a and a metal back plate 124b, and the plurality of side plates 124a and the metal back plate 124b are connected to each other, and surrounded by the metal back plate 124b for arranging cold cathode fluorescent lamps. 122 , and the light emitted by each CCFL tube 122 will be initially mixed in the frame 124 , and then pass through the diffuser plate 126 to form a surface light source with relatively uniform brightness.

It should be noted that when the backlight assembly 120 is turned on, the CCFL tube 122 is very close to the metal back plate 124b. Therefore, the CCFL tube 122 and the metal back plate 124b will form a capacitor, and a parasitic capacitance will be generated therebetween. In this way, the current input to the cold cathode fluorescent lamp 122 will not only light the cold cathode fluorescent lamp 122, but also charge the capacitor at the same time, resulting in insufficient current for lighting the cold cathode fluorescent lamp 122, thus causing the cold cathode fluorescent lamp The brightness of the tube 122 cannot reach the originally required brightness. At this time, higher electric power must be provided to make the brightness of CCFL tube 122 reach the originally required brightness. In this way, more electric power must be consumed.

Generally speaking, the design of the backlight assembly 120 must be as thin and light as possible, so as to comply with the current trend of thinner and lighter displays. Therefore, on the premise of not increasing the total thickness of the backlight assembly 120, if the relative position between the cathode fluorescent lamp tube 122 and the metal back plate 124b is adjusted, that is, the distance H1 is widened so as to reduce the distance between the cold cathode fluorescent lamp tube 122 and the metal back plate 124b. If the parasitic capacitance between the back plates 124b is large, the distance H2 between the cathode fluorescent lamp tubes 122 and the diffusion plate 126 will be relatively reduced. This may cause the distance between the cathode fluorescent lamp tube 122 and the diffuser plate 126 to be too close, thus resulting in poor uniformity of the surface light source provided by the backlight assembly 120 .

In addition, as the size of the liquid crystal display panel 110 increases day by day, the size of the CCFL tube 122 will increase correspondingly, and the electric power for lighting the CCFL tube 122 must also increase accordingly. However, the above parasitic capacitance is directly proportional to the surface area of the CCFL 122 , and the higher the driving voltage of the CCFL 122 is, the more charges are accumulated on the metal back plate 124 b. In other words, the larger the surface area of the CCFL tube 122 or the higher its driving voltage, the larger the parasitic capacitance between the CCFL tube 122 and the metal back plate 124b. In this way, the leakage current between the metal back plate 124b and the cold cathode fluorescent lamp 122 will be larger, which will reduce the safety of the overall liquid crystal display 100 in use, and the electric power consumption of the backlight assembly 120 (power consumption) is also bound to increase with the leakage current. In addition, the existing converter 130 cannot accurately control the current output to the CCFL tube 122 due to the influence of parasitic capacitance and leakage current.

Contents of the invention

In view of this, the purpose of the present invention is to provide a backlight assembly to solve the problems of leakage current and excessive power consumption of the existing backlight assembly.

Another object of the present invention is to provide a backlight assembly to improve the safety of the overall liquid crystal display in use.

To achieve the above and other purposes, the present invention provides a backlight assembly, which includes a frame, a plurality of light sources and an optical film. Wherein, the frame has a bottom surface and a plurality of side surfaces, the bottom surface has a plurality of through holes and is separated from each other, and the bottom surface and the side surfaces are connected. The above-mentioned light sources are respectively fixed in the frame corresponding to the through holes, and the optical film is arranged on the frame and located above the light source.

In one embodiment of the present invention, the backlight assembly further includes an insulating reflection sheet disposed on the bottom surface.

In the backlight assembly according to an embodiment of the present invention, the material of the insulating reflective sheet includes polypropylene or saturated polyester.

In the backlight assembly according to an embodiment of the present invention, the above-mentioned light sources include cold cathode fluorescent lamps, external electrode cold cathode lamps, cold cathode fluorescent flat lamps or light emitting diodes.

In the backlight assembly according to an embodiment of the present invention, the optical film includes a diffusion film, a brightness enhancement film, a prism film or a combination of these films.

The present invention provides a liquid crystal display, which includes the above-mentioned backlight assembly and a liquid crystal display panel, and the liquid crystal display panel is arranged above the optical film of the backlight assembly.

The invention provides a backlight assembly, which includes a frame, a plurality of light sources and an optical film. Wherein, the frame has a bottom surface and a plurality of side surfaces, and the bottom surface has a plurality of recesses separated from each other, and the bottom surface and the side surfaces are connected. The above-mentioned light sources are respectively fixed in the frame corresponding to the recessed parts, and the optical film is arranged on the frame and located above the light source.

In the backlight assembly according to an embodiment of the present invention, the above-mentioned concave portion is a concave surface.

In the backlight assembly according to an embodiment of the present invention, the above-mentioned concave surface is an arc surface.

In the backlight assembly according to an embodiment of the present invention, the above-mentioned light source is located at the center of the concave surface.

The backlight assembly according to an embodiment of the present invention further includes an insulating reflection sheet disposed on the bottom surface.

In the backlight assembly according to an embodiment of the present invention, the material of the insulating reflective sheet includes polypropylene or saturated polyester.

In the backlight assembly according to an embodiment of the present invention, the above-mentioned light sources include cold cathode fluorescent lamps, external electrode cold cathode lamps, cold cathode fluorescent flat lamps or LED arrays.

In the backlight assembly according to an embodiment of the present invention, the above-mentioned optical film includes a diffusion film, an enhancement film, a prism film or a combination of these films.

一第二方向呈交错排列，上述的第一方向与第二方向实质上垂直。此外，光源分别对应于第一方向而固定于框架内，而光学膜片配置于框架上，且位于光源上方。The invention provides a backlight assembly, which includes a frame, a plurality of light sources and an optical film. Wherein, the frame has a bottom surface and multiple side surfaces, and the bottom surface and the side surfaces are connected. The above-mentioned bottom surface has a plurality of through holes and a plurality of depressions, and the through holes and depressions are arranged in a staggered manner along a first direction, and the through holes and the depressions

A second direction is staggered, and the above-mentioned first direction is substantially perpendicular to the second direction. In addition, the light sources are respectively fixed in the frame corresponding to the first direction, and the optical film is arranged on the frame and located above the light source.

In the backlight assembly according to an embodiment of the present invention, the above-mentioned concave portion may be a concave surface.

In the backlight assembly according to an embodiment of the present invention, the above-mentioned concave surface may be an arc surface.

In the backlight assembly according to an embodiment of the present invention, each light source mentioned above may be located at the center of each concave surface.

The backlight assembly according to an embodiment of the present invention further includes an insulating reflection sheet disposed on the bottom surface.

In the backlight assembly according to an embodiment of the present invention, the material of the insulating reflective sheet may include polypropylene or saturated polyester.

In the backlight assembly according to an embodiment of the present invention, the above-mentioned light sources may include cold cathode fluorescent lamps, external electrode cold cathode lamps, cold cathode fluorescent flat lamps or light emitting diodes.

In the backlight assembly according to an embodiment of the present invention, the above-mentioned optical film may include a diffusion film, an enhancement film, a prism film or a combination of films.

The present invention provides a liquid crystal display, which includes the above-mentioned backlight assembly and a liquid crystal display panel. Wherein, the liquid crystal display panel is disposed above the optical film of the above-mentioned backlight assembly.

To sum up, in the backlight assembly of the liquid crystal display of the present invention, the light source is fixed in the frame corresponding to the through hole or the recessed portion, so as to effectively improve the distance between the light source and the bottom surface of the frame without changing the thickness of the backlight assembly. The problem of parasitic capacitance is generated due to too close distance, so that the backlight assembly can reduce the consumption of electric power and avoid the phenomenon of leakage current. In addition, the security of the overall liquid crystal display can also be improved accordingly.

In order to make the above and other objects, features and advantages of the present invention more comprehensible, preferred embodiments are exemplified below and described in detail with accompanying drawings.

Description of drawings

FIG. 1 is a schematic cross-sectional view of a conventional liquid crystal display.

FIG. 2 is a schematic cross-sectional view of a liquid crystal display according to a first embodiment of the present invention.

FIG. 3 is a schematic cross-sectional view of a liquid crystal display according to a second embodiment of the present invention.

FIG. 4A is a bottom rear view of a liquid crystal display according to a third embodiment of the present invention.

Fig. 4B is a schematic cross-sectional view along the section line A-A' in Fig. 4A.

Detailed ways

first embodiment

FIG. 2 is a schematic cross-sectional view of a liquid crystal display according to a first embodiment of the present invention. Please refer to FIG. 2 , the liquid crystal display 200 of the present invention includes a liquid crystal display panel 210 and a backlight assembly 220 . Wherein, the liquid crystal display panel 210 is disposed above the backlight assembly 220 , and the backlight assembly 220 is suitable for providing a side light source to the liquid crystal display panel 210 so that the liquid crystal display panel 210 can achieve display purposes. Generally speaking, an inverter 230 can be disposed next to the backlight assembly 220 , and the inverter 230 is suitable for converting DC power into AC power required to light the backlight assembly 220 .

Please refer to FIG. 2 again, the backlight assembly 220 includes a plurality of light sources 222 , a frame 224 and an optical film 226 . Wherein, the frame 224 has a plurality of side surfaces 224a and a bottom surface 224b. It is worth noting that the bottom surface 224b has a plurality of through holes C and is separated from each other, and the bottom surface 224b is connected to the side surface 224a. The light sources 222 mentioned above are respectively fixed in the frame 224 corresponding to the through holes C. Common light sources 222 include cold cathode fluorescent lamps (Cold Cathode Fluorescent Lamp, CCFL), external electrode cold cathode lamp tubes (External Electrode Fluorescent Lamp, EEFL), Cold cathode fluorescent flat lamp (Cold Cathode Fluorescence Flat Lamp, CCFFL) or light emitting diode (LED), etc. Those skilled in the art can select different types of light sources 222 according to actual needs, and there is no limitation here.

In addition, the above-mentioned optical film 226 is disposed on the frame 224 and located above the light source 222 . The optical film 226 includes a diffusion film, an enhancement film, a prism film or a combination of these films. Specifically, the liquid crystal display panel 210 will be disposed above the optical film 226. If the optical film 226 is a diffuser, the light emitted by the light source 222 will pass through the optical film 226 to form a more uniform brightness. surface light source. If the optical film 226 is a prism sheet, the direction of the light emitted by the light source 222 can be adjusted by means of the prism sheet.

It will be explained in detail here that in this embodiment, a through hole C is formed on the bottom surface 224b, and the light source 222 is arranged corresponding to the through hole C, so that the overall thickness H of the backlight assembly 220 and the connection between the light source 222 and the bottom surface can be maintained. In the case of the relative position of 224b, the parasitic capacitance value between the CCFL tube 122 and the metal back plate 124b is effectively reduced. Of course, the shape of the above-mentioned through hole C is not limited here, and the shape of the through hole C can be appropriately adjusted according to the size, shape or quantity of the light source 222 used.

In other words, the backlight assembly 220 of the present invention can not only effectively suppress the leakage current caused by the charge accumulation on the bottom surface 224 b due to the parasitic capacitance effect, but also further improve the safety of the backlight assembly 220 in use. In addition, the converter 230 can also accurately control the current to be output to the light source 222 , so that the operation of the light source 222 can meet the needs of displaying images on the liquid crystal display panel 210 .

What should be emphasized here is that the present invention does not need to change the position of the light source 222, so the original relative position between the light source 222 and the optical film 226 can be maintained, so as to avoid making it too close to the optical film 226 due to improper adjustment of the position of the light source 222 , causing the phenomenon that the light emitted by the optical film 226 is not uniform.

In addition, in this embodiment, an insulating reflective sheet R can also be disposed on the bottom surface 224b, so that the light emitted by the light source 222 can be effectively reused through the reflection of the insulating reflective sheet R. The insulating reflection sheet R is made of polypropylene (PP) or saturated polyester (PolyethyleneTerephthalate, PET).

second embodiment

FIG. 3 is a schematic cross-sectional view of a liquid crystal display according to a second embodiment of the present invention. Please refer to FIG. 3 , the liquid crystal display 300 of the second embodiment of the present invention is very similar to the first embodiment, and the main difference between the two is that: the bottom surface 224c of the backlight assembly 220 of this embodiment has a plurality of depressions C1, and separated from each other. The light sources 222 are respectively fixed in the frame 224 corresponding to the recesses C1. The above-mentioned concave portion C1 can be designed as a concave surface, such as an arc surface, and the light source 222 can be disposed at the center of the concave surface. In other words, this embodiment improves the prior art by forming the recessed portion C1. The cold cathode fluorescent lamp 122 (as shown in FIG. 1 ) is too close to the metal back plate 124b (as shown in FIG. 1 ), which causes parasitic lighting during lighting. Capacitance and leakage current issues. Certainly, the shape of the above-mentioned recessed portion C1 is not limited here, and the shape of the recessed portion C1 can be properly adjusted according to the size, shape or quantity of the light source 222 used.

third embodiment

FIG. 4A is a bottom rear view of a liquid crystal display according to a third embodiment of the present invention, and FIG. 4B is a schematic cross-sectional view along line A-A' in FIG. 4A. Please refer to FIG. 4A and FIG. 4B. In the example of the liquid crystal display 400 of the embodiment of the present invention, a plurality of depressions C1 and through holes C are simultaneously formed on the bottom surface 224d, and the depressions C1 and the through holes C are formed along a first direction X. are alternately arranged, and the recessed portions C1 and the through holes C are also arranged alternately along a second direction Y. Wherein, the first direction X and the second direction Y may be perpendicular to each other.

Specifically, the first direction X may be a horizontal direction, and the second direction Y is a vertical direction, but it is not limited here. In addition, the extension direction of each light source 222 can be selected to correspond to the first direction X or the second direction Y. It is worth noting that the alternate arrangement of the recesses C1 and the through holes C can effectively reduce the parasitic capacitance between the light source 222 and the corresponding bottom surface 224d. The above-mentioned concave portion C1 is, for example, a concave surface, and the concave surface can be designed as an arc surface, and the above-mentioned light source 222 can be disposed at the center of the concave surface. Of course, the shape of the recessed portion C1 and the through hole is not limited here, and the shape of the recessed portion C1 and the through hole can be adjusted appropriately according to the size, shape or quantity of the light source 222 used.

It should be noted here that, on the premise that the overall thickness H of the backlight assembly 220 remains unchanged, the shape of the current transformer 230 can be appropriately changed according to the shape of the concave portion C1 .

In summary, the liquid crystal display and the backlight assembly of the present invention have at least the following advantages:

1. Since the light source is fixed in the frame corresponding to the through-hole or the concave surface, under the premise of maintaining the original thickness of the backlight assembly and not changing the relative position of the light source and the optical film, it can effectively improve the distance between the light source and the bottom surface of the frame due to the close distance between the light source and the frame. There is a problem of parasitic capacitance during lighting. Therefore, the backlight assembly can reduce electric power consumption and avoid electric leakage. In addition, since the relative position of the light source and the optical film will not change, this helps to maintain the uniformity of the surface light source formed by the light emitted by the light source passing through the optical film.

2. Since the backlight assembly can effectively suppress the occurrence of leakage current, the overall power consumption of the liquid crystal display of the present invention will be greatly reduced.

3. Because the backlight assembly of the present invention can effectively suppress parasitic capacitance and leakage current. Therefore, the converter can more accurately control the current to be output to the light source.

Although the present invention has been disclosed above with preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art may make some changes and modifications without departing from the spirit and scope of the present invention. Therefore, the present invention The scope of protection should be defined by the claims.

Claims (21)

1. backlight assembly comprises:

One framework has a bottom surface and a plurality of side, and wherein this bottom surface has a plurality of perforations and is separated from each other, and this bottom surface is connected with those sides;

A plurality of light sources correspond respectively to those perforations and are fixed in this framework; And

One blooming piece is disposed on this framework, and is positioned at those light source tops.

2. backlight assembly as claimed in claim 1 is characterized in that, also comprises an insulation reflector plate, is disposed on this bottom surface.

3. backlight assembly as claimed in claim 2 is characterized in that, the material of this insulation reflector plate comprises polypropylene or saturated polynary ester.

4. backlight assembly as claimed in claim 1 is characterized in that, those light sources comprise cathode fluorescent tube, outer electrode cold cathode fluorescent lamp, cold-cathode fluorescent plant lamp pipe or light emitting diode.

5. backlight assembly as claimed in claim 1 is characterized in that this blooming piece comprises the combination of diffusion sheet, brightening piece, prismatic lens or those diaphragms.

6. backlight assembly comprises:

One framework has a bottom surface and a plurality of side, and wherein this bottom surface has a plurality of depressed parts and is separated from each other, and this bottom surface is connected with those sides;

A plurality of light sources correspond respectively to those depressed parts and are fixed in this framework; And

One blooming piece is disposed on this framework, and is positioned at those light source tops.

7. backlight assembly as claimed in claim 6 is characterized in that, those depressed parts are concave surface.

8. backlight assembly as claimed in claim 7 is characterized in that, those concave surfaces are arc surface.

9. backlight assembly as claimed in claim 8 is characterized in that, respectively this light source is positioned at the respectively center of this concave surface.

10. backlight assembly as claimed in claim 6 is characterized in that, also comprises an insulation reflector plate, is disposed on this bottom surface.

11. backlight assembly as claimed in claim 10 is characterized in that, the material of this insulation reflector plate comprises polypropylene or saturated polynary ester.

12. backlight assembly as claimed in claim 6 is characterized in that, those light sources comprise cathode fluorescent tube, outer electrode cold cathode fluorescent lamp, cold-cathode fluorescent plant lamp pipe or light emitting diode.

13. backlight assembly as claimed in claim 6 is characterized in that, this blooming piece comprises the combination of diffusion sheet, brightening piece, prismatic lens or those diaphragms.

14. a backlight assembly comprises:

One framework, have a bottom surface and a plurality of side, this bottom surface is connected with those sides, wherein this bottom surface has a plurality of perforations and a plurality of depressed part, those perforations and those depressed parts are staggered along a first direction and arrange, and those perforations and those depressed parts are staggered along a second direction to be arranged, and this first direction is vertical in fact with this second direction;

A plurality of light sources correspond respectively to this first direction and are fixed in this framework; And

One blooming piece is disposed on this framework, and is positioned at those light source tops.

15. backlight assembly as claimed in claim 14 is characterized in that, those depressed parts are concave surface.

16. backlight assembly as claimed in claim 15 is characterized in that, those concave surfaces are arc surface.

17. backlight assembly as claimed in claim 16 is characterized in that, respectively this light source is positioned at the respectively center of this concave surface.

18. backlight assembly as claimed in claim 14 is characterized in that, also comprises an insulation reflector plate, is disposed on this bottom surface.

19. backlight assembly as claimed in claim 18 is characterized in that, the material of this insulation reflector plate comprises polypropylene or saturated polynary ester.

20. backlight assembly as claimed in claim 14 is characterized in that, those light sources comprise cathode fluorescent tube, outer electrode cold cathode fluorescent lamp, cold-cathode fluorescent plant lamp pipe or light emitting diode.

21. backlight assembly as claimed in claim 14 is characterized in that, this blooming piece comprises the combination of diffusion sheet, brightening piece, prismatic lens or those diaphragms.

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