TWI435145B - Light source circuit module, backlight module, and display apparatus with reflective structure of light - Google Patents

Description

Light source circuit module, backlight module and display with light reflection structure

The invention relates to a light source circuit module and a backlight module and a display having the light source circuit module, in particular to a light source circuit module, a backlight module and a display with a light reflecting structure.

With the rapid development of liquid crystal display (LCD) manufacturing technology, it has the advantages of lightness, power saving and no radiation, so that liquid crystal displays are widely used in various electronic devices with display requirements, such as personal digital assistants. Personal Digital Assistant (PDA), notebook computer, digital camera, digital video camera, computer screen and LCD TV. Since the liquid crystal display panel in the liquid crystal display device is a non-self-luminous display panel, it is necessary to use the light provided by the backlight module to generate a display screen.

With the improvement of the light-emitting diode (LED) illumination technology, the LED illumination power is increasing, so many backlight modules have been used as LEDs. In a smaller display screen, it uses a smaller number of LEDs to provide sufficient brightness; however, in larger display screens, such as LCD TVs, it must use a larger number of LEDs to enable the entire display. The panel provides sufficient backlighting. Taking a liquid crystal television as an example, the direct type backlight module mainly comprises a circuit board, a plurality of LED light sources uniformly distributed on the circuit board, and a diffusion plate. After the light emitted by the plurality of LED light sources enters the diffusing plate, the diffusing plate is emitted after being diffused and mixed to provide a uniform backlight required for the liquid crystal module.

However, at present, liquid crystal televisions are continuously designed to reduce the thickness of the body. In addition to the limitation of the thickness of the liquid crystal module, the thickness of the backlight module is also limited. The thickness of the backlight module is reduced by the thickness of the diffuser and the distance between the LED and the diffuser. Although the thickness reduction of the diffuser plate will affect the light mixing effect, the shortening of the distance between the LED and the diffuser plate is greater, and the light intensity distribution into the diffuser plate is rather uneven, so that the diffusion plate has a limited effect of improving the light distribution, and the most common. The phenomenon that the LCD TV produces mura is such that the display quality of the LCD TV is not good.

In response to this problem, although there is a backlight module coated with a reflective material on a circuit board, light can be reflected in a place where there is no light source, so as to improve the uneven distribution of light intensity entering the diffusion plate. Although this method can improve the phenomenon of moiré, the reflectivity of the board is fixed, and the intensity of the light reaching the board is weakened as the distance from the source increases, causing the light reflected from the board. The intensity also decreases with the distance from the distance source, so the overall intensity of the light reflected from the circuit board farther away from the light source is still weaker, so that the overall light distribution is still concentrated, and the phenomenon of moiré remains. Exist, the improvement effect is limited. Therefore, there is a need to provide a light-emitting architecture that can provide a light source of sufficient uniformity to solve the above problems under the condition that the thickness of the backlight module is reduced.

One of the objectives of the present invention is to provide a light source circuit module that utilizes a plurality of reflective layers to form a light reflecting structure that utilizes a change in area of a highly reflective reflective block to improve the uniformity of light generated by the light source circuit module.

The light source circuit module of the present invention comprises a circuit board, a first reflective layer and a second reflective layer. The circuit board includes a plurality of electrical connection regions, each of which is electrically fixed to a light-emitting diode. The first reflective layer is formed directly on a surface of the circuit board, and the first reflective layer has a first reflectivity. The second reflective layer is directly formed on the first reflective layer to partially cover the first reflective layer. The second reflective layer has a second reflectivity, and the second reflectance is greater than the first reflectivity. The two reflective layer includes a plurality of reflective blocks distributed on the first reflective layer, and the area of the reflective block increases as the distance between the electrical connection regions closest to the distance increases.

Thereby, the larger the area of the reflective block farther from the plurality of electrical connection regions, the stronger the intensity of the light that can be reflected by the reflective block, so that the region farther away from the plurality of electrical connection regions can be compensated for. The problem of insufficient distribution further enables the light source circuit module as a whole to provide a light source that is more uniform than the light source module of the prior art which only forms a single reflective reflectance layer on the circuit board.

Another object of the present invention is to provide a light source circuit module in which a light reflection structure is formed by using a plurality of reflective layers, which utilizes a change in area of a high reflectance hollow region to improve the uniformity of light generated by the light source circuit module.

The light source circuit module of the present invention comprises a circuit board, a first reflective layer and a second reflective layer. The circuit board includes a plurality of electrical connection regions, each of which is electrically fixed to a light-emitting diode. The first reflective layer is formed directly on a surface of the circuit board, and the first reflective layer has a first reflectivity. The second reflective layer is directly formed on the first reflective layer to partially cover the first reflective layer. The second reflective layer has a second reflectivity, and the second reflectance is greater than the first reflectivity. The two reflective layers comprise a plurality of hollowed out regions distributed over the first reflective layer, the area of the hollowed out regions decreasing as the distance between the electrically connected regions closest to them is increased.

Thereby, the smaller the area of the hollow region farther from the plurality of electrical connection regions, the stronger the intensity of the light that can be reflected by the second reflective layer, so that it can be used to compensate the region farther from the plurality of electrical connection regions. The problem of insufficient light distribution further enables the light source circuit module as a whole to provide a light source that is more uniform than the light source module of the prior art which only forms a single reflective reflectance layer on the circuit board.

Another object of the present invention is to provide a backlight module using the light source circuit module of the present invention to provide a more uniform backlight than the backlight module of the prior art.

The backlight module of the present invention comprises a light source circuit module and a diffusion plate of the invention. The diffusion plate is disposed on a circuit board of the light source circuit module. Since the light source circuit module improves the uniformity of the provided light, as described above, the light entering the diffusing plate is diffused and mixed by the diffusing plate, and then the diffusing plate is emitted to exhibit a backlight according to the prior art. The module has a more uniform backlight to avoid the generation of moiré.

Another object of the present invention is to provide a display employing the backlight module of the present invention to provide a more uniform image display than the display of the prior art.

The backlight module of the present invention comprises a backlight module of the invention and a display panel. The display panel is disposed on the diffusion plate of the backlight module. Since the backlight module can provide a more uniform backlight than the backlight module of the prior art, as described above, the display panel can use the uniform backlight to display high-quality images with more uniform brightness and more saturated colors.

Compared with the foregoing technology, the light source circuit module of the present invention forms a light reflection structure by using a plurality of reflective layers, and the ratio of the coverage area of the second reflective layer to the first reflective layer is changed to achieve adjustment by the first reflective layer. And an effect of the reflectivity of the reflective structure formed by the second reflective layer, so that the intensity of the light reflected from the region farther from the plurality of electrical connection regions is stronger, so as to overcome the problem of insufficient light distribution, thereby making the light source circuit The module as a whole can provide a more uniform light distribution than prior art light source modules that only form a single reflective reflective layer on the board. In short, the light source circuit module of the present invention utilizes a light reflection structure with a variable reflectivity as a variable or design freedom for improving the uniformity of the backlight, thereby increasing the design flexibility of the backlight structure. The backlight module of the present invention utilizes the light provided by the diffusion plate to diffuse and mix light, thereby providing a more uniform backlight than the backlight module of the prior art, and effectively suppressing moiré; further, the display of the present invention That is, the backlight module is utilized to provide high-quality image display with more uniform brightness and more saturated colors.

The advantages and spirit of the present invention will be further understood from the following detailed description of the invention.

Referring to FIG. 1 and FIG. 2, FIG. 1 is a plan view of a light source circuit module 1 according to a first preferred embodiment of the present invention, and FIG. 2 is a view of the light source circuit module 1 along the first embodiment. Cutaway line XX section view. The light source circuit module 1 includes a circuit board 12, a first reflective layer 14, and a second reflective layer 16. The circuit board 12 includes a plurality of electrical connection regions 122 (represented by a square). Each of the electrical connection regions 122 can include two electrode pads 1222 electrically connected to and fixed to the light-emitting diode 2. The first reflective layer 14 is formed directly on one surface 124 of the circuit board 12 and has a first reflectivity R1. The second reflective layer 16 is directly formed on the first reflective layer 14 to partially cover the first reflective layer 14 and has a second reflectivity R2 that is greater than the first reflectivity R1. The second reflective layer 16 includes a plurality of reflective blocks 162 distributed on the first reflective layer 14. The area of the reflective block 162 increases as the distance D between the electrical connection regions 122 closest to the distance increases. In the second figure, the reflection block 162 is indicated by hatching. In addition, in the embodiment, the distance D may be defined as the distance between the centroid of the reflective block 162 and the centroid of the closest electrical connection region 122; however, the invention is not limited thereto.

In general, the regions on the circuit board 12 have different reflectivities due to the different distribution of the reflective blocks 162. The reflectivity is determined by the first reflective layer 14 and the second reflective layer 16. The common contribution of the reflective block 162, for example, the operational definition of the reflectivity of a certain region may be that the area ratio P1 of the first reflective layer 14 exposed in the region is multiplied by the first reflectivity R1 and the second reflective layer 16 The area ratio P2 exposed by the reflective block 162 is multiplied by the sum of the second reflectances R2 (P1×R1+P2×R2), and its property is an average reflectance, wherein the size of the region is set to consider the actual reflective region. The size of the block 162 is to avoid distortion of the reflectance calculation due to improper selection of the target area. In this embodiment, since the area of the reflective block 162 that is far from the electrical connection region 122 is large, the reflectance of the region of the circuit board 12 that is far from the electrical connection region 122 is large. In application, the light emitted from the self-luminous diode 2 is partially reflected by other components combined with the light source circuit module 1, such as the light guide plate of the backlight module, and the reflected light can be reflected by multiple reflections. Far from the light-emitting diode 2. Although the light reaching the square farther from the light-emitting diode 2 is weaker, the reflectance of the circuit board 12 farther from the light-emitting diode 2 or the electrical connection region 122 is larger, which is relative to The incident light reflects a strong reflected light, so that the intensity attenuation can be compensated, so that the light reflected from the light-emitting diode 2 can be maintained at a certain distance even if it is far away from the light-emitting diode 2 In other words, the light source circuit module 1 can provide a relatively uniform light distribution to the outside, and solves the problem that the backlight module of the prior art only forms a single reflectivity on the circuit board cannot effectively improve the concentrated distribution of light.

In addition, since the reflective block 162 is discretely distributed, the introduction of the average reflectance is only for facilitating analysis and understanding of the light reflecting structure formed by the first reflective layer 14 and the second reflective layer 16, which is not intended to be In the embodiment, the reflective block 162 and the first reflective layer 14 form a structure that is homogeneously reflective. In addition, reflected light or light transmission after multiple reflections It is usually accompanied by a phenomenon of intensity attenuation. If the degree of attenuation is significant, in practice, the area of the reflective block 162 should be further increased to compensate for the aforementioned attenuation.

In addition, in this embodiment, the first reflectivity R1 ranges between 30% and 98%, and the second reflectance R2 ranges between 90% and 100%. When the first reflective layer 14 and the second reflective layer 16 are used, it should be noted that the second reflectivity R2 should be greater than the first reflectivity R1. For example, the material of the first reflective layer 14 is selected to include a metal or a metal compound, such as barium sulfate ( The reflectance is about 98%), and the material of the second reflective layer 16 is silver powder (reflectance greater than 99%); however, the invention is not limited thereto. Moreover, the first reflective layer 14 and the second reflective layer 16 may be sequentially applied to the circuit board 12 by means of printing. However, the present invention is not limited thereto, and for example, the sheet may be disposed on the circuit board 12.

Referring to FIG. 3 and FIG. 4, FIG. 3 is a plan view of a light source circuit module 3 according to a second preferred embodiment of the present invention, and FIG. 4 is a third embodiment of the light source circuit module 3 along the third embodiment. Cutaway line YY section view. The light source circuit module 3 includes a circuit board 32, a first reflective layer 34 and a second reflective layer 36. The circuit board 32 includes a plurality of electrical connection regions 322 (represented by a square). Each of the electrical connection regions 322 includes two electrode pads 3222 electrically connected and fixed to the light-emitting diode 2. The first reflective layer 34 is formed directly on one surface 324 of the circuit board 32 and has a first reflectivity R1. The second reflective layer 36 is directly formed on the first reflective layer 34 to partially cover the first reflective layer 34 and has a second reflectivity R2 that is greater than the first reflectivity R1. The second reflective layer 36 includes a plurality of hollow regions 362 distributed in the first reflective layer 34, the area of the hollowed out area 362 decreases as the distance D between the electrical connection areas 322 closest to the distance increases, wherein for ease of illustration, the hollowed out area 362 is hatched in the third figure, and the hollowed out area 362 The first reflective layer 34 exposed therein is not otherwise marked. Similarly, in the present embodiment, the distance D may be defined as the distance between the centroid of the hollow region 362 and the centroid of the closest electrical connection region 322; however, the invention is not limited thereto.

In this embodiment, the regions on the circuit board 32 have different reflectivities due to the different distribution of the hollow regions 362. The reflectivity is similarly contributed by the first reflective layer 34 and the second reflective layer 36. The operational definition of the reflectance of the region may also be based on the ratio of the area exposed by the first reflective layer 34 and the second reflective layer 36 respectively, as described in the foregoing first preferred embodiment regarding the reflectance. Narration. In this embodiment, the area of the hollow region 362 that is far from the electrical connection region 122 is small, in other words, the proportion of the second reflective layer 36 covering the first reflective layer 34 is higher in this region, so the circuit board 32 is on the circuit board 32. The area farther from the electrical connection region 322 has a higher reflectance. It is to be noted that, in the first preferred embodiment, the light source circuit module 1 changes the area of the reflective block 162 to increase the proportion of the second reflective layer 16 covering the first reflective layer 14, thereby achieving the purpose of controlling the reflectance. In the second preferred embodiment, the light source circuit module 3 changes the area of the hollow region 362 to increase the proportion of the second reflective layer 36 covering the first reflective layer 34, and the same can be achieved for controlling the reflectivity. In short, both of them use the ratio of changing the exposed areas of the first reflective layers 14, 34 and the second reflective layers 16, 36 to achieve the purpose of controlling the reflectance, so the basic spirit of the two technical means is not different. Therefore, other descriptions about the first reflective layer 34 and the second reflective layer 36 can be referred to the foregoing. The description of the first preferred embodiment will not be repeated.

Please refer to FIG. 5, which is a partial cross-sectional view of a backlight module 5 according to a third preferred embodiment of the present invention. The backlight module 5 includes the light source circuit module 1 and a diffusion plate 52. The diffusion plate 52 is disposed on the circuit board 12. For the description of the components of the light source circuit module 1, please refer to the foregoing first preferred embodiment. For the sake of explanation, in FIG. 5, the light emitted from the light-emitting diode 2 is represented by a broken line and includes paths such as refraction and reflection.

As shown in FIG. 5, not all of the light emitted from the light-emitting diode 2 directly enters the diffusing plate 52, and at least a portion thereof is reflected by the diffusing plate 52 toward the circuit board 12. The reflected light will be reflected by the light reflecting structure formed by the first reflective layer 14 and the second reflective layer 16, and the secondary reflected light still only partially enters the diffusing plate 52, and the remaining portion is diffused by the diffusing plate 52. The reflected, multi-reflected light can reach a region far from the light-emitting diode 2. Thereby, the diffusing plate 52 can receive light not only near the light-emitting diode 2 but also light reflected by the first reflective layer 14 and the second reflective layer 16 away from the light-emitting diode 2, so that the diffusion plate 52 The board 52 receives more uniform incident light than the backlight module of the conventional point source, and the light distribution received by the diffuser 52 is more uniform than the backlight module which is known to form only a single reflectivity reflective layer on the board. Further, the diffusion plate 52 can provide a more uniform backlight than the conventional backlight module; in other words, the backlight module of the present invention can reduce the moiré phenomenon by designing the degree of change of the reflectance of the light reflection structure. Greatly improve the uniformity of the backlight.

In addition, in the embodiment, the diffusing plate 52 may further include a plurality of opaque dots 522, which can block the amount of light entering the diffusing plate 52, so as to reduce the difference between the intensities of the light entering from the respective regions of the surface of the diffusing plate 52. It also contributes to the uniformity of the backlight provided by the backlight module 5. Moreover, if the opaque dots 522 are composed of a reflective material, the light reflected by the opaque dots 522 can be further transmitted to a region farther from the illuminating diode 2 to increase the distance from the illuminating diode 2 The intensity of the light reflected by the light reflecting structure can further improve the uniformity of the backlight provided by the backlight module 5. It is to be noted that the backlight module of the present invention is not limited to the light source circuit module 1 as a light source providing device, and the embodiments of the various light source circuit modules, or variations and combinations thereof, can be used as the backlight module of the present invention. The set of light source provides a device.

Referring to Figure 6, a partial cross-sectional view of a display 7 in accordance with a fourth preferred embodiment of the present invention. The display 7 includes the backlight module 5 and a display panel 72. The display panel 72 is disposed on the diffuser 52. For the description of the backlight module 5, refer to the description of the third preferred embodiment. Let me repeat. As shown in FIG. 6 , the backlight module 5 can provide a relatively uniform backlight (the light path is indicated by a broken line) by the diffusing and mixing light of the diffusing plate 52. The generating mechanism is as described above, and will not be described again. . Thereby, the display panel 72 of the display 7 of the present invention can utilize the uniform backlight provided by the backlight module 5 to display a uniform brightness of the display than the light reflecting structure of the reflective layer which only forms a single reflectivity on the circuit board. High-quality images with more saturated colors. It is to be noted that the backlight module of the display of the present invention is not limited to the backlight module 5 in FIG. 6 , and other backlight modules formed based on the embodiments of the foregoing various light source circuit modules or their variants and combinations , can also be applied to the display of the present invention Display.

Compared with the foregoing technology, the light source circuit module of the present invention uses a plurality of reflective layers to form a light reflection structure with a change in reflectance, so that the intensity of the light that can be reflected from the region farther from the plurality of electrical connection regions is stronger, so that the light source The circuit module as a whole can provide a more uniform light distribution than the prior art light source module that only forms a single reflective reflective layer on the board. In short, the light source circuit module of the present invention has a light reflection structure with a variable reflectivity as a variable or design freedom for improving the uniformity of the backlight, so that the design flexibility of the backlight structure can be increased. The backlight module of the present invention utilizes the light source module to provide a more uniform backlight than the backlight module of the prior art, and effectively suppresses moiré. The display of the present invention utilizes the backlight module to provide a high quality image display with more uniform brightness and more saturated colors.

The above are only the preferred embodiments of the present invention, and all changes and modifications made to the scope of the present invention should be within the scope of the present invention.

1, 3‧‧‧Light source circuit module

2‧‧‧Lighting diode

5‧‧‧Backlight module

7‧‧‧ display

12, 32‧‧‧ circuit board

14, 34‧‧‧ first reflective layer

16, 36‧‧‧ second reflective layer

52‧‧‧Diffuser

72‧‧‧ display panel

122, 322‧‧‧Electrical connection area

124, 324‧‧‧ surface

162‧‧‧Reflecting blocks

362‧‧‧ hollow area

522‧‧‧ opaque outlets

1222, 3222‧‧‧ electrode pad

D‧‧‧Distance

1 is a top plan view of a light source circuit module in accordance with a first preferred embodiment of the present invention.

Fig. 2 is a cross-sectional view of the light source circuit module along the cut surface line X-X in Fig. 1.

3 is a top plan view of a light source circuit module in accordance with a second preferred embodiment of the present invention.

Fig. 4 is a cross-sectional view of the light source circuit module along the cut surface line Y-Y in Fig. 3.

Figure 5 is a cross-sectional view showing a backlight module in accordance with a third preferred embodiment of the present invention.

Figure 6 is a partial cross-sectional view of a display in accordance with a fourth preferred embodiment of the present invention.

1. . . Light source circuit module

2. . . Light-emitting diode

5. . . Backlight module

12. . . Circuit board

14. . . First reflective layer

16. . . Second reflective layer

52. . . Diffuser

122. . . Electrical connection area

162. . . Reflective block

522. . . Opaque dot

1222. . . Electrode pad

Claims (10)

A light source circuit module comprising: a circuit board comprising a plurality of electrical connection regions, each of the electrical connection regions being capable of electrically fixing a light emitting diode; a first reflective layer directly formed on the circuit board a first reflective layer having a first reflectivity; and a second reflective layer directly formed on the first reflective layer to partially cover the first reflective layer, the second reflective layer having a first The second reflectivity is greater than the first reflectivity, and the second reflective layer includes a plurality of reflective blocks distributed on the first reflective layer, and the area of the reflective block is the closest to the distance The distance between the connection areas increases and increases. The light source circuit module of claim 1, wherein the first reflectance ranges between 30% and 98%. The light source circuit module of claim 1, wherein the second reflectivity ranges between 90% and 99%. The light source circuit module of claim 1, wherein the material of the first reflective layer comprises a metal or a metal compound. The light source circuit module of claim 1, wherein the first reflective layer is made of barium sulfate. The light source circuit module of claim 1, wherein the material of the second reflective layer comprises a metal or a metal compound. The light source circuit module of claim 1, wherein the second reflective layer is made of silver powder. A light source circuit module comprising: a circuit board comprising a plurality of electrical connection regions, each of the electrical connection regions being capable of electrically fixing a light emitting diode; a first reflective layer directly formed on the circuit board a first reflective layer having a first reflectivity; and a second reflective layer directly formed on the first reflective layer to partially cover the first reflective layer, the second reflective layer having a first The second reflectivity is greater than the first reflectivity, and the second reflective layer includes a plurality of hollow regions distributed on the first reflective layer, and the area of the hollowed out region is closest to the electrical connection region The distance between them increases and decreases. A backlight module, comprising: the light source circuit module according to any one of claims 1 to 8, and a diffusion plate disposed on the circuit board. A display comprising: a backlight module as claimed in claim 9; and a display panel disposed on the diffuser.