CN100543555C - Side light source backlight module - Google Patents

Abstract

A side light source backlight module comprises a substrate, a light guide plate and a light source group. The light guide plate sets up in the upper surface of base plate and has a income plain noodles, and the light source group sets up on the base plate and the income plain noodles of next-door neighbour light guide plate, and wherein, the light source group includes: the white light LED packages comprise blue LED crystal grains and yellow fluorescent powder; a plurality of red LED packages for blending a red spectrum missing from the white LED package; and the driving chip also comprises a timing module and a storage unit, and the storage unit is internally provided with a decline parameter relation table. The invention can improve the problem that the white balance of the known side light source backlight module is easy to be out of order, and according to the invention, the possibility that the development chromaticity is not vivid due to lack of red spectrum in the white light LED package in the known side light source backlight module can be avoided.

Description

Side light backlight module

technical field

The present invention relates to an edge-type backlight module, in particular to an edge-type backlight module with a red light emitting diode (Light Emitting Diode, LED) regulating white balance mechanism.

Background technique

Please refer to FIG. 1A and FIG. 1B , FIG. 1A is a schematic side sectional view of a known side light source backlight module; FIG. 1B shows the light source group in FIG. 1A . The backlight module 10 includes a base (back bezel) 12 , a light guide plate 14 , multilayer optical films (not shown), a reflector 16 and a light source group 20 . The light source group 20 includes a circuit board 21 and a light emitting diode (LED) 22 . The function of the backlight module 10 is to provide a uniform surface light source to a display panel, such as a liquid crystal panel.

In the backlight module 10 , the base 12 has a substrate 122 and has an extension 124 extending from the peripheral portion of the substrate 122 , which can be used to install or cover other elements of the backlight module 10 .

The light guide plate 14 is disposed on the substrate 122 , and the light source group 20 is disposed on a side end of the light guide plate 14 , and the side end is the light incident surface of the light guide plate 14 . The light enters the light guide plate 14 from the side end of the light guide plate 14 and is scattered in the light guide plate 14 . The light guide plate 14 usually has a specific optical pattern, such as a v-cut pattern, so that the light scattered therein can exit the light guide plate 14 more uniformly. Multi-layer optical films, such as upper and lower diffusion films and upper and lower brightness enhancement films, are usually arranged on the light guide plate 14 to enhance the quality of the light provided by the backlight module 10 .

In order to enhance the light utilization efficiency of the backlight module 10 , a reflective sheet 16 is usually disposed on the inner surface of the base 12 or coated with a reflective material. Taking the reflective sheet 16 as an example, the reflective sheet 16 disposed on the inner surface of the extension portion 124 can be used to make the light from the light source group 20 enter the light guide plate 14 more efficiently, while the reflective sheet 16 disposed on the inner surface of the substrate 122 can make the light more efficient. Efficiently applied to the backlight module 10 .

Among the light source group 20, the light emitting diode 22 is a component that mainly converts electrical energy into light energy. Currently, the commonly used illuminant is a white light LED; and the circuit board 21 has a circuit required for operating the light emitting diode 22. The two usually After the manufacturing is completed, the light emitting diodes 22 are installed on the circuit board 21 to complete the light source group 20 to facilitate the assembly of the backlight module 10 .

At present, in the side light backlight module, the mainstream white LED production method is the packaging structure obtained by adding blue LED grains (430nm) to YAG phosphor powder (555nm). This method uses the lens principle to mix complementary blue light and yellow light to obtain white light seen by the naked eye. The luminous efficiency (301m/W) of the blue LED chip is excellent compared with other monocrystalline LED chips, and compared with RGB polycrystalline chips, it has the advantages of simple drive circuit design and low production cost; however, its spectrum The red band is extremely weak, which will cause the lack of red in the spectrum, and when it illuminates a red object, it will show a yellowish red. As for the liquid crystal display, it will make the overall displayed color particularly weak when the red signal is present, and the overall color is not bright enough.

In view of the defects of the above-mentioned packaging structure of white light LEDs, related companies have also proposed some corresponding solutions in the hope of solving the lack of red light. For example, when making white LED packages, red or orange phosphors are added to YAG phosphors to improve the lack of red spectrum.

However, the above-mentioned solutions can easily affect the service life of the packaged white LED. Different additive materials will react with the existing yellow phosphor to some extent. In practice, it is found that there will be problems such as by-products and easy hydrolysis. Further research Affect the lifespan and brightness of white LEDs.

In addition to making improvements in the production of white LED packages, there are also other companies that improve other components in the process of assembling side light backlight modules. For example, Nichia in Japan has processed the color filter to solve The color cast problem mentioned above. The lack of red spectrum reinforcement is performed after the white LED package is completed. The advantage is that it will not affect the excellent luminous efficiency and service life of the white LED package; however, the processing on the color filter will cause the overall side light source backlight module process cumbersome and rising costs.

Therefore, how to improve the lack of red spectrum in known side light backlight modules, and further avoid the cumbersome process and cost increase of the overall backlight module is necessary for current development.

Contents of the invention

The main purpose of the present invention is to improve the white balance imbalance problem of the known side light source backlight module.

Another object of the present invention is to avoid the problem of lack of red spectral band in the side light backlight module.

Another object of the present invention is to avoid the problem that the brightness of the side light source backlight module decreases due to the time of use.

The invention provides a side light source backlight module, which includes a substrate, a light guide plate and a light source group. The light guide plate is arranged on the upper surface of the substrate and has a light incident surface, and the light source group is arranged on the substrate and is adjacent to the light incident surface of the light guide plate, wherein the light source group includes: a plurality of white LED packages, and the white LED packages are composed of blue color LED crystal grains plus yellow phosphor; multiple red LED packages, the multiple red LED packages are used to reconcile the red spectrum that the white LED package lacks; and a driver chip, the driver chip also includes A timing module and a storage unit, the storage unit builds a decay parameter relation table. The light source group is further connected with a flexible circuit board, and the driving chip on the flexible circuit board applies current to the light source group to convert electric energy into light energy, so as to achieve the effect of light.

From the above, the present invention has indeed solved the problem that the white balance of the known side light source backlight module is easy to be out of adjustment. According to the present invention, the white LED package in the known side light source backlight module lacks the red spectrum, resulting in indistinct chromaticity. The possibility of the problem has been avoided. In addition, the present invention further adds a timing module to the driver chip to maintain the consistency of the brightness of the light source module.

The advantages and spirit of the present invention, as well as more detailed implementations, can be further understood through the following implementations and the accompanying drawings.

Description of drawings

Through the following detailed description combined with the accompanying icons, the above content and many advantages of this invention can be easily understood, wherein:

FIG. 1A is a schematic side sectional view of a known side light source backlight module;

Figure 1B shows the light source group in Figure 1A;

FIG. 2A is a schematic top view of the side light source backlight module disclosed in the present invention;

FIG. 2B is a schematic side sectional view of the side light source backlight module disclosed in the present invention.

Description of main component symbols:

10 Backlight module 12 Base

122 base plate 124 extension

14 Light guide plate 16 Reflector

20 light source group 21 circuit board

22 Light-emitting diodes 3 Backlight module

31 Substrate 311 Upper surface

32 Light guide plate 321 Light-emitting surface

322 Light incident surface 33 Light source group

331 white LED package 332 red LED package

4 flexible circuit board

Detailed ways

Please refer to FIGS. 2A-2B , which are respectively a schematic top view and a schematic side sectional view of the side light source backlight module disclosed in the present invention. The backlight module 3 includes a substrate 31 , a light guide plate 32 and a light source group 33 . The light guide plate 32 is a light-permeable acrylic flat plate, the upper surface of which is a light-emitting surface 321 , and the lower surface thereof is combined with the substrate 31 ; one side surface of the light guide plate 32 is a light-incoming surface 322 .

The light source group 33 is arranged on the upper surface 311 of the substrate 31 and is adjacent to the light incident surface 322 of the light guide plate 32; The light source group 33 applies current to convert electrical energy into light energy, so as to achieve the effect of lighting.

After entering the light guide plate 32 , the light emitted by the light source group 33 is scattered by the light guide plate 32 and output from the primary light surface 321 of the light guide plate 32 to assist the liquid crystal panel (not shown) to display images.

In one embodiment, a multilayer optical film (not shown) is provided on the light guide plate 32. The multilayer optical film can be an upper diffusion sheet, an upper brightness enhancement sheet, a lower diffusion sheet, a lower brightness enhancement sheet or a combination thereof, which can enhance The quality of light provided by the overall backlight module 3 .

To further illustrate, the light source group 33 of the side light source backlight module disclosed in the present invention is composed of a plurality of white LED packages 331 and a plurality of red LED packages 332. In this embodiment, the white LED packages 331 and the red LED packages 332 For interleaved configuration. The white LED package 331 is composed of blue LED crystal grains plus yellow phosphor powder. As mentioned in the background art, the white LED package composed of blue LED crystal grains and yellow phosphor powder has excellent luminous efficiency. However, The red band of its spectrum is extremely weak, which will cause the lack of red in the spectrum, and when it illuminates a red object, it will show a yellowish red. As for the liquid crystal display, it will make the overall displayed color particularly weak when the red signal is present, and the overall color is not bright enough. The light source group in the present invention is interlaced between the white LED packages 331 by a plurality of red LED packages 332 to reconcile the red spectrum lacking in the white LED packages 331 and maintain the white balance of the overall backlight module 3 . Display panels of different sizes and different application fields will have different LED luminance and brightness requirements. In the embodiment of the present invention, the ratio of the configuration amount of the red LED package to the white LED package is not limited, because the ratio should be due to different It can be adjusted according to the needs of the panel.

In one embodiment, the driver chip on the flexible circuit board further includes a timing module and a storage unit, wherein the storage unit has a built-in decay parameter relationship table. The decay parameter relation table is a relation table of light source usage time versus reinforcing current. The decay parameter relation table is created by detecting and recording the curve of the light source group 33 usage time versus decay brightness in advance. The driver chip can actively calculate the use time of the light source group 33 through the timing module, and perform current reinforcement of a specific magnitude after a specific use time through the decay parameter relationship table to maintain the light source group 33 at a predetermined brightness.

In the prior art, whether it is improving the packaging process of white light LEDs or improving other optical elements during the assembly process of the backlight module, there are problems that affect the service life of the entire backlight module or increase the production cost. However, in the present invention, through the setting of the single-chip red LED package 332, the light source group 33 does not need to be additionally processed in the process, and the backlight module does not need to add more related processing processes to the existing optical film. Adding red LED packaging to the configuration, adding this step at the technical end of the backlight module assembly process, successfully solved the known problem of white balance imbalance without increasing the production cost too much.

To sum up, the present invention has indeed improved the problem that the white balance of the known side light source backlight module is easy to be out of adjustment. According to the present invention, the white LED package in the known side light source backlight module lacks the red spectrum, resulting in indistinct chromaticity. The possibility of the problem has been avoided. In addition, the present invention further adds a timing module to the driver chip to maintain the consistency of the brightness of the light source module.

Although the present invention has been described above with preferred examples, it is not intended to limit the spirit and entities of the present invention to the above-mentioned examples. Those skilled in the art can easily understand and use other elements or methods to produce the same effect. Therefore, modifications made without departing from the spirit and scope of the present invention should be included in the scope of the claims.

Claims (6)

1. A side light source backlight module, comprising: a substrate; A light guide plate is arranged on the upper surface of the substrate, and the light guide plate has a light incident surface; A light source group, arranged on the substrate and adjacent to the light incident surface of the light guide plate; It is characterized in that the light source group includes: A plurality of white light LED packages, the white light LED package is composed of blue LED crystal grains plus yellow phosphor; a plurality of red LED packages for reconciling the red spectrum lacking in the white LED package; and A drive chip, the drive chip also includes a timing module and a storage unit, the storage unit is built with a decay parameter relationship table. 2 . The side light source backlight module according to claim 1 , wherein the decay parameter relationship table is a relationship table of light source usage time versus reinforcement current. 3 . 3. The side light source backlight module according to claim 2, wherein the driver chip performs current reinforcement at a specific time through the timing module and the decay parameter relationship table to maintain the light source group at a predetermined brightness. 4. The side light source backlight module according to claim 1, further comprising a multi-layer optical film disposed on the surface of the light guide plate. 5 . The side light source backlight module according to claim 4 , wherein the multilayer optical film is selected from an upper diffusion sheet, an upper brightness enhancement sheet, a lower diffusion sheet, a lower brightness enhancement sheet or a combination thereof. 6. The side light backlight module according to claim 4, further comprising a reflective sheet or a reflective material disposed on the upper surface of the substrate.

Images