CN201062761Y - Backlight module - Google Patents

Abstract

The utility model discloses a backlight module, comprising: a light guide plate and a light source. The light guide plate comprises: a light emitting surface; a reflective surface, which is arranged opposite to the light emitting surface, and the reflective surface comprises a curved surface; and at least one notch, which is arranged on one side of the light guide plate, and the notch comprises a first plane and a second plane, wherein the first plane is connected to the light emitting surface, and the second plane is connected to the curved surface. The light source is accommodated in the notch of the light guide plate. Thus, the backlight module of the utility model can reduce the volume occupied by the light source, and increase the brightness and uniformity of the backlight module.

Description

Backlight module

technical field

The utility model relates to a backlight module, in particular to a backlight module suitable for a plane display device.

Background technique

In recent years, due to the increasing importance of displays in people's lives, in addition to using computers or the Internet, televisions, mobile phones, personal digital assistants (PDAs) and digital cameras, etc., must transmit information through display control. Compared with traditional kinescope displays, flat-panel displays of the new era have the advantages of light weight, small size and no radiation, but there is still room for improvement in problems such as brightness and power consumption.

Among many emerging flat panel display technologies, liquid crystal display (LCD) is currently the mainstream. Since the liquid crystal display is a non-self-illuminating display, the display function must be generated by an external light source. Therefore, the backlight module plays the role of the light source in the liquid crystal display and is one of the important components of the liquid crystal display.

Most of the traditional display backlights use cold cathode lamps (CCFL) to illuminate flat panel displays. The cold cathode fluorescent tube is limited in its application range because of its short service life, high power consumption, and mercury metal contained in the tube, which is easy to pollute the environment. The light emitting diode (LED) is a high-efficiency active light source, which has the advantages of low power consumption, high luminance output and small size, so it becomes an excellent light source.

Please refer to FIG. 1 , which is a perspective view of a conventional backlight module 10 , which mainly includes a light guide plate 11 and a plurality of LEDs 12 , which are light sources of the backlight module 10 . The light guide plate 11 of the existing backlight module 10 has a similar rectangular structure, and the thickness of the light guide plate 11 and the thickness of the light emitting diodes 12 are as equal as possible to prevent loss and attenuation of panel luminance. The light sources (light emitting diodes 12) of the backlight module 10 are arranged in the form of light bars (Light Bar) on the side of the light guide plate 11, so that light enters the light guide plate 11 from the side. Generally speaking, the closer the distance between the light emitting diodes 12 and the light guide plate 11 is, the higher the luminance of the obtained backlight module will be. Therefore, as shown in FIG. 1 , when the LED 12 is attached to the light guide plate 11 , the light utilization efficiency of the LED 12 is the highest, but it is easy to cause a bright band at or near the interface where the LED 12 enters the light guide plate 11 .

Moreover, the current demand for flat panel displays has become increasingly thinner. The existing backlight module 10 arranges light-emitting diodes 12 in the form of light bars (Light Bar) on the side of the light guide plate 11, which will inevitably increase the occupied space of the backlight module 10. To place the LED 12.

Therefore, how to increase the luminance and uniformity of the existing backlight module and reduce the occupied volume of the backlight module is an urgent problem to be solved at present.

Utility model content

In view of this, the purpose of this utility model is to provide a backlight module, including: a light guide plate and a light source, the light guide plate includes: a light-emitting surface; a reflective surface, which is arranged facing the light-emitting surface, the reflective surface It includes a curved surface; and at least one notch is arranged on one side of the light guide plate, the notch includes a first plane and a second plane, wherein the first plane is connected to the light-emitting surface, and the second plane is connected to the curved surface connected; the light source is accommodated in the gap of the light guide plate. Through this, the volume occupied by the light source of the backlight module is reduced, and the luminance and uniformity of the backlight module are increased.

In the backlight module of the present invention, the arrangement pattern of the notches of the light guide plate is not limited, and the number of the light sources is not limited, depending on the size of the light guide plate or the brightness requirement. In the backlight module of the present invention, at least one side of the light guide plate has a gap, preferably a single side of the light guide plate has a gap or two opposite sides of the light guide plate have gaps. In the backlight module of the present invention, preferably, there is a notch on one side. Moreover, the number of light sources accommodated in each notch is not limited, preferably, one notch accommodates several light sources or one notch accommodates one light source.

In the backlight module of the present invention, the angle between the first plane and the second plane of the notch of the light guide plate is not limited, preferably the angle between the first plane of the notch and the second plane is a right angle, and the notch The second plane is lower than the light emitting surface of the light guide plate.

In the backlight module of the present invention, the thickness of the notch of the light guide plate is not limited, and is preferably equal to or smaller than the thickness of the light source so that the light source can be completely accommodated in the notch to facilitate space use.

In the backlight module of the present invention, the form of the curved surface of the light guide plate is not limited, and it is preferably a smooth curved surface, so as to facilitate light to achieve a good reflection effect.

In the backlight module of the present invention, the light source is not limited to be attached to the light guide plate, as long as it is as close as possible to the light guide plate, preferably the light source is attached to the light guide plate to reduce light intensity loss.

Moreover, in the backlight module of the present invention, the material of the light guide plate can be any transparent material, preferably acrylic resin or polycarbonate resin. The light guide plate can also be other transparent materials, including acrylic ester, polyester, thermoplastic resin, transparent resin, transparent glass and transparent ceramic ).

In the backlight module of the present invention, the types of these light sources are not limited, and are preferably light emitting diodes (LEDs). Moreover, the light emitting colors of these light sources are not limited, and they are preferably white light sources.

In the backlight module of the present invention, the backlight module may optionally include at least one optical film set disposed on the light-emitting surface of the light guide plate, the optical film set is preferably a prism sheet, a diffusion sheet or combination.

In addition, the present invention provides a flat display device, including: a display panel; and a backlight module located on one side of the display panel; wherein, the backlight module includes a light guide plate and a light source, and the light guide plate includes a light output surface; a reflective surface is arranged facing the light-emitting surface, and the reflective surface includes a curved surface; at least one notch is arranged on one side of the light guide plate, and the notch includes a first plane and a second plane, wherein The first plane is connected to the light-emitting surface, and the second plane is connected to the curved surface; the light source is accommodated in the gap of the light guide plate.

The flat display device adopting the backlight module can reduce the volume occupied by the light source because the light source can be accommodated in the gap, so the volume of the flat display device is also reduced accordingly. Moreover, when the light from the light source enters the light guide plate, it can be reflected by the curved surface of the light guide plate, so the luminance and uniformity of the backlight module can be increased, and the luminance and uniformity of the display screen can be improved accordingly.

In the flat display device of the present invention, the display panel can be any non-self-illuminating display panel, preferably a liquid crystal display panel.

In the flat panel display device of the present invention, the arrangement pattern of the notches of the light guide plate is not limited, and the number of the light sources is not limited, but depends on the size of the light guide plate or the brightness requirement. In the flat panel display device of the present invention, at least one side of the light guide plate has a notch, preferably a single side of the light guide plate has a notch, or two opposite sides of the light guide plate have notches. In the flat panel display device of the present invention, preferably, one side has a notch. Moreover, the number of light sources accommodated in each notch is not limited, preferably, one notch accommodates several light sources or one notch accommodates one light source.

In the flat panel display device of the present invention, the angle between the first plane and the second plane of the notch of the light guide plate is not limited, preferably the angle between the first plane of the notch and the second plane is a right angle, and the The second plane of the notch is lower than the light emitting surface of the light guide plate.

In the flat-panel display device of the present invention, the thickness of the notch of the light guide plate is not limited, and is preferably equal to or smaller than the thickness of the light source so that the light source can be completely accommodated in the notch to facilitate the use of space.

In the flat panel display device of the present invention, the curved surface of the light guide plate is not limited, and is preferably a smooth curved surface, so as to achieve a good reflection effect of light.

In the flat panel display device of the present invention, the light source is not limited to be attached to the light guide plate, as long as it is as close as possible to the light guide plate. It is preferable that the light source is attached to the light guide plate to reduce light intensity loss.

Moreover, in the flat panel display device of the present invention, the material of the light guide plate can be any transparent material, preferably acrylic resin or polycarbonate resin. The light guide plate can also be other transparent materials, including acrylic ester, polyester, thermoplastic resin, transparent resin, transparent glass and transparent ceramic ).

In the flat panel display device of the present invention, the types of these light sources are not limited, and are preferably light emitting diodes (LEDs). Moreover, the light emitting colors of these light sources are not limited, and they are preferably white light sources.

In addition, in the flat display device of the present invention, the backlight module may optionally include at least one optical film disposed on the light-emitting surface of the light guide plate, and the optical film group is preferably a prism sheet, a diffusion sheet or its combination.

The beneficial effect of the utility model is that the luminance and uniformity of the existing backlight module are increased, and the occupied volume of the backlight module is reduced.

Description of drawings

FIG. 1 is a three-dimensional schematic diagram of an existing backlight module;

Fig. 2 is a three-dimensional schematic diagram of a backlight module in a preferred embodiment of the present invention;

Fig. 3 is a schematic cross-sectional view of Fig. 2;

4 is a side view of a liquid crystal display device in a preferred embodiment of the present invention;

5 is a three-dimensional schematic diagram of a backlight module in another preferred embodiment of the present invention;

FIG. 6 is a three-dimensional schematic diagram of a backlight module in another preferred embodiment of the present invention.

[Description of main component symbols]

Backlight module 10, 20, 40, 50 Light guide plate 11, 21, 41, 51

Light-emitting diodes 12, 22, 44, 53 Light-emitting surface 23

curved surface 24 reflective surface 25

Gap 26, 42, 43, 52 First plane 27

Second plane 28 diffuser 29, 31

Prism sheet 30 LCD panel 60

Detailed ways

These drawings in the embodiments of the present utility model are simplified schematic diagrams. These icons only show the components related to the utility model, the components shown are not the actual implementation, the number and shape of the components in the actual implementation are a selective design, and the layout of the components Possibly more complicated.

Embodiment one

Please refer to FIG. 2 and FIG. 3 at the same time. FIG. 2 is a schematic perspective view of a backlight module 20 according to a preferred embodiment of the present invention, and FIG. 3 is a schematic cross-sectional view along line AA' of FIG. 2 . The backlight module 20 of this embodiment mainly includes a light guide plate 21 and a plurality of light sources, the light sources are white light emitting diodes 22, and the light guide plate 21 is made of acrylic resin.

Please refer to FIG. 3 , the light guide plate 21 of this embodiment mainly has a light emitting surface 23 , a reflecting surface 25 and a notch 26 . The reflective surface is opposite to the light emitting surface 23 , and the reflective surface includes a curved surface 24 . The notch 26 is disposed on a side of the light guide plate 21 . The light guide plate 21 of this embodiment has a notch 26 on only one side, and the notch 26 includes a first plane 27 and a second plane 28, the first plane 27 is connected to the light emitting surface 23, and the second plane 28 is connected to the light emitting surface 23. Surface 24 is connected. The notch 26 accommodates a plurality of light emitting diodes 22, and in this embodiment the depth H of the notch 26 is slightly greater than the height h of the light emitting diodes 22, so the light emitting diodes 22 will be completely accommodated in the notch 26 without additional increase. The volume occupied by the entire backlight module 20 . The light emitting diodes 22 of this embodiment are attached to the light guide plate 21 to reduce the loss of light intensity.

In the backlight module 20 of this embodiment, the reflective surface 25 of the light guide plate 21 can optionally be provided with dots (not shown in the figure) or a reflective layer (not shown in the figure). In this embodiment, the reflective surface 25 of the light guide plate 21 can selectively form dots by printing or use sandblasting, etching, cutting, etc. to make the reflective surface 25 a rough surface, so as to scatter the light guided into the light guide plate 21 . The reflective surface 25 of this embodiment is formed by printing dots (not shown in the figure). In this embodiment, the reflective layer (not shown in the figure) can be a metal layer deposited under the reflective surface 25 or a thin film disposed under the reflective surface 25 . The reflective sheet under the reflective surface 25 in this embodiment is an aluminum metal layer (not shown) deposited under the reflective surface 25 .

In addition, in this embodiment, two diffusion sheets 29 , 31 and a prism sheet 30 are optionally arranged on the light-emitting surface 23 of the light guide plate 21 to uniformize the light output of the backlight module 20 .

Therefore, when the incident light from the LED 22 enters the light guide plate 21, most of the incident light will hit the curved surface 24 of the light guide plate 21 first, and the curved surface 24 will totally reflect the incident light, thereby reducing the loss of the incident light, and at the same time The incident light is scattered to make the light guided into the light guide plate 21 more uniform, and the guided light can be used more effectively. Then, the light guided into the light guide plate 21 will repeatedly perform total reflection in the light guide plate 21 until it encounters the dots (not shown) on the reflective surface 25 of the light guide plate 21 and destroys the total reflection, allowing the light to pass through the light guide plate 21. The light is emitted from the light emitting surface 23 of 21, and finally the light is uniformly emitted by optical films such as diffusion sheets 29, 31 and prism sheet 30, so that the light emitted by the backlight module 20 with good luminance and uniformity can be obtained. In this embodiment, the curved surface 24 of the light guide plate 21 is a smooth curved surface, which can obtain better reflection effect.

Please refer to Table 1, which shows the results of light simulations performed by optical simulation software under the same parameter conditions for the existing backlight module 10 (see FIG. 1 ) and the backlight module 20 of this embodiment.

Table 1

The backlight module of Embodiment 1 Existing backlight module Center brightness Center brightness

6555nit 2410nit overall brightness overall brightness 5143nit 2270nit

As can be seen from Table 1, compared with the existing backlight module 10 (refer to FIG. 1), the backlight module 20 of this embodiment can not only prevent the light emitting diodes 22 from increasing the occupied space of the entire backlight module, but also increase the luminance and brightness of the backlight module. Evenness.

FIG. 4 is a schematic side view of a liquid crystal display device using the backlight module 20 of this embodiment. As shown in FIG. 4 , the backlight module 20 is disposed on one side of the liquid crystal display panel, so that the liquid crystal display panel 60 is adjacent to the light emitting surface 23 of the backlight module 20 . Therefore, the light emitted from the backlight module 20 can enter the liquid crystal display panel 60 to provide a uniform light source for the liquid crystal display panel.

Embodiment two

The backlight module of the present utility model can be changed and modified depending on the size of the light guide plate or the brightness requirement. Please refer to the perspective view of the backlight module in Fig. 5, the structure of the backlight module 40 of this embodiment is roughly the same as that shown in Embodiment 1, the only difference is that the light guide plate 41 of the backlight module 40 of this embodiment has two The notches 42 and 43 on the two opposite sides of the light board 41 and other structures are the same as those in the first embodiment.

Likewise, the backlight module 40 of this embodiment can prevent the LEDs 44 from increasing the occupied space of the entire backlight module, and can increase the brightness and uniformity of the backlight module.

Embodiment three

The backlight module of the present utility model can be changed and modified depending on the size of the light guide plate or the brightness requirement. Please refer to the perspective view of the backlight module 50 in FIG. Notch 52, and each notch 52 accommodates a light emitting diode 53, the rest of the structure is the same as the first embodiment.

Likewise, the backlight module 50 of this embodiment can prevent the LEDs 53 from increasing the occupied space of the entire backlight module, and can increase the brightness and uniformity of the backlight module.

The above-mentioned embodiments are only examples for convenience of description, and the scope of rights claimed by the utility model shall be subject to the description of the scope of patent application, rather than limited to the above-mentioned embodiments.

Claims (9)

1. backlight module comprises:

One LGP is characterized in that comprising:

One exiting surface;

One reflecting surface is and this exiting surface subtend setting that this reflecting surface comprises a curved surface; And

At least one breach is arranged at a side of this LGP, and this breach comprises one first plane and one second plane, and wherein this first plane is connected with this exiting surface, and this second plane is connected with this curved surface; And

One light source is in this breach of ccontaining this LGP.

2. backlight module as claimed in claim 1 is characterized in that, this light source is a light emitting diode.

3. backlight module as claimed in claim 1 is characterized in that, a degree of depth of this breach is more than or equal to a height of this light source.

4. backlight module as claimed in claim 1 is characterized in that, the single side of this LGP has this breach.

5. backlight module as claimed in claim 1 is characterized in that, two relative sides of this LGP have this breach.

6. backlight module as claimed in claim 1 is characterized in that this backlight module also comprises at least one optical diaphragm group, is disposed on this exiting surface of this LGP.

7. backlight module as claimed in claim 6 is characterized in that, this optical diaphragm group is prismatic lens, diffusion sheet or its combination.

8. backlight module as claimed in claim 1 is characterized in that, the material of this LGP is acrylic resin or polycarbonate resin.

9. backlight module as claimed in claim 1 is characterized in that, this backlight module is the side entrance back module.

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