CN103969893A - A partition device and a direct-lit backlight module comprising the same - Google Patents

Abstract

The invention provides a separating device and a direct type backlight module comprising the same. The direct type backlight module comprises a bottom plate, a plurality of backlight sources and an optical element plate, wherein the backlight sources are positioned between the bottom plate and the optical element plate. The direct type backlight module further comprises a plurality of separating devices, each separating device is arranged around the corresponding backlight source, and the separating devices comprise: a support column for supporting the optical element board; the rotating motor is positioned below the supporting column; and the partition plate is fixedly connected with the rotary motor. The rotary motor drives the partition sheet to rotate around the backlight source so as to form an independent area to be matched with the picture partition lighting of the liquid crystal screen. Compared with the prior art, the invention can eliminate dark lines on the contact surface of the existing clapboard and the optical element plate, can blur the boundary of unnatural light and dark boundaries in the existing module and reduce the light leakage situation.

Description

A partition device and a direct-lit backlight module comprising the same

technical field

The invention relates to a direct-type backlight module in a liquid crystal display device, in particular to a separating device for the direct-type backlight module.

Background technique

Liquid Crystal Display (LCD) technology has always been applied in portable electronic products such as notebook computers, mobile phones, digital cameras, camcorders, and personal digital assistants (Personal Digital Assistance, PDA). In addition to these small portable products, the manufacturing technology of large-size LCD panels has also matured recently. For example, desktop liquid crystal displays are gradually replacing traditional cold cathode ray tube (Cathode Ray Tube, CRT) display screens. Among them, the liquid crystal panel (LCD panel) is the most critical component in this field, but it does not emit light itself, and needs to be provided with a backlight source to display. Currently, there are various backlight technologies, and in large-size liquid crystal display products, a direct-type backlight module (Bottom Lighting Module) is often used as the backlight of the liquid crystal panel.

In the prior art, generally speaking, a direct type backlight module includes a partition partition, a plurality of backlight sources and an optical element board. Here, the partition partition is arranged between the bottom plate of the backlight module and the optical element board, which includes a plurality of grids, each grid corresponds to a backlight source and encloses the backlight source into an independent area, so that , Local dimming (local dimming) design can cooperate with the LCD screen for partition lighting, thereby improving the contrast of the display screen. In addition, a reflective sheet or a reflective surface layer can be laid on the upper surface of the bottom plate, so as to prevent the light from the backlight from escaping, so that the light can be reflected to the optical element board above the backlight.

However, the above-mentioned direct type backlight module also has many defects. For example, the distance between the optical element board and the partition partition is relatively small, and the partition with a certain wall thickness will easily generate dark lines above the partition when the adjacent backlights are all turned on, which will affect the display quality. In addition, if one of the adjacent backlights is in the bright state and the other is in the dark state, an unnatural light-dark border can also be created where the partition divider meets the optics plate. Furthermore, the contact between the partition partition and the optical element board is surface contact, and when the partition partition and the optical element board are displaced relative to each other, it is easy to cause the surface of the optical element board to be scratched. What is even more unfavorable is that the shape of the partition pattern will be limited by the placement of partition partitions. Once the partition is placed in a fixed position, the partition pattern will be determined accordingly, making the form of regional dimming single and unable to realize backlight scanning. The pattern change of (backlight scanning) has a positive effect on improving the contrast of the picture.

In view of this, how to design a novel direct-type backlight module, especially a partition device for the direct-type backlight module, to effectively improve or eliminate the above-mentioned defects and deficiencies is a problem to be solved urgently by relevant technical personnel in the industry.

Contents of the invention

Aiming at the above-mentioned defects of the prior art direct-type backlight module in the area dimming design, the present invention provides a direct-type backlight module, which includes a novel partition device, by which the partition device A variety of regional dimming patterns or backlight scanning patterns can be combined to improve picture contrast.

According to one aspect of the present invention, a direct type backlight module is provided, comprising a bottom plate, a plurality of backlight sources and an optical element board, the backlight source is located between the bottom plate and the optical element board, wherein the The direct type backlight module also includes a plurality of partitions, each partition is arranged around the corresponding backlight, and the partitions include:

a support column, which is in point contact with the lower surface of the optical element board, and used to support the optical element board;

a rotary motor located below the support column; and

partition plate, fixedly connected with the rotary motor,

Wherein, the rotating motor drives the partition sheet to rotate around the backlight source, thereby forming an independent area for lighting up in accordance with the screen partitions of the liquid crystal screen.

In one embodiment, the partition device further includes a fixing portion, the bottom plate further includes a through hole, and the fixing portion passes through the through hole, so that the partition device is fixed on the bottom plate.

In one embodiment, the fixing part has a base and two hooks integrally formed with the base, the base and the hooks are respectively located on opposite sides of the bottom plate, and the bottom plate is embedded in The accommodating space formed by the base and the hook.

In one embodiment, the rotary motor is a cylinder, the base is a disk, and the diameter of the disk is larger than the diameter of the bottom surface of the cylinder.

In one embodiment, the direct-type backlight module further includes a reflective sheet located above the base plate, the reflective sheet has an opening at a position corresponding to the through hole, and the fixing parts of the partitioning device pass through in turn. The opening and the through hole are provided.

In one embodiment, the optical element plate is a diffuser plate.

In one embodiment, the respective surfaces of the supporting column, the rotating motor and the partition plate of the partitioning device are sprayed with high-reflectivity materials.

In one embodiment, the support column is a cone or a regular pyramid.

According to another aspect of the present invention, a separation device for a direct-type backlight module is provided, the direct-type backlight module includes a base plate, a plurality of backlight sources and an optical element board, the backlight sources are located between the base plate and the Between the optical element boards, wherein the separating device is arranged around the corresponding backlight source, including:

a support column, which is in point contact with the lower surface of the optical element board, and used to support the optical element board;

a rotary motor located below the support column; and

partition plate, fixedly connected with the rotary motor,

Wherein, the rotating motor drives the partition sheet to rotate around the backlight source, thereby forming an independent area for lighting up in accordance with the screen partitions of the liquid crystal screen.

In one embodiment, the partition device further includes a fixing part having a base and two hooks integrally formed with the base, and the base plate further includes a through hole. The base and the hook are respectively located on opposite sides of the bottom plate, and the hook penetrates through the through hole of the bottom plate, so that the bottom plate is inserted into the cavity formed by the base and the hook. space, so that the partition device is fixed on the bottom plate.

Using the partition device of the present invention and the direct type backlight module comprising the partition device, the backlight source is located between the bottom plate and the optical element board, each partition device is arranged around the corresponding backlight source, and the partition device includes a support column, a rotation motor And the partition sheet, the support column is in point contact with the lower surface of the optical element board, the rotation motor is located under the support column, the partition sheet is fixedly connected to the rotation motor, and the rotation motor drives the partition sheet to rotate around the corresponding backlight to form an independent The area is illuminated in accordance with the screen partitions of the LCD screen to improve the contrast of the screen. Compared with the prior art, the direct-lit backlight module of the present invention can eliminate the dark line (darkline) on the contact surface between the existing partition board and the optical element board, and can blur the unnatural boundary between light and shade in the current module, reducing the light leaks. In addition, the supporting column and the optical element board of the present invention are in point contact, so the relative displacement between the supporting column and the optical element board can be avoided to cause scratches.

Description of drawings

Readers will have a clearer understanding of various aspects of the present invention after reading the detailed description of the present invention with reference to the accompanying drawings. in,

FIG. 1 shows a schematic structural view of a direct-lit backlight module in the prior art;

FIG. 2A shows a schematic structural diagram of a partition device for a direct-lit backlight module according to an embodiment of the present invention;

Figure 2B shows another view of the spacer of Figure 2A;

FIG. 3 shows a schematic diagram of two adjacent backlight sources being on when the partition device in FIG. 2A is assembled to a direct-type backlight module;

FIG. 4 shows a schematic diagram of two adjacent backlights being on and off respectively when the partition device in FIG. 2A is assembled to a direct-lit backlight module;

Fig. 5(a) ~ Fig. 5(c) show the schematic diagrams of regional dimming by rotating partition plates with different shapes in an alternative embodiment of the partition device in Fig. 2A; and

FIG. 6( a ) and FIG. 6( b ) show schematic diagrams of different backlight scanning patterns formed by the direct-lit backlight module of the present invention through the partition device in FIG. 2A .

Detailed ways

In order to make the technical content disclosed in this application more detailed and complete, reference may be made to the drawings and the following various specific embodiments of the present invention, and the same symbols in the drawings represent the same or similar components. However, those skilled in the art should understand that the examples provided below are not intended to limit the scope of the present invention. In addition, the drawings are only for schematic illustration and are not drawn according to their original scale.

The specific implementation manners of various aspects of the present invention will be further described in detail below with reference to the accompanying drawings.

FIG. 1 shows a schematic structural diagram of a direct-lit backlight module in the prior art. Referring to FIG. 1 , the direct type backlight module includes a bottom plate 100 , a spacer 102 , and one or more optical element plates 104 . A plurality of backlight sources (such as LED light sources) 106 are disposed on the chassis 100 . The spacer 102 is located between the optical element board 104 and the base plate 100 . In order to realize local dimming, the dividing device 102 is divided into a plurality of grids, and each grid corresponds to a plurality of backlight sources 106, and these backlight sources 106 are surrounded into an independent area, so as to cooperate with the picture of the liquid crystal screen to perform dimming. The partition lights up.

However, the existing direct-lit backlight modules have great limitations in local dimming. This is because the partitioning device 102 is often designed in advance, resulting in the shape of the partitioning pattern being constrained by the arrangement of the partitioning device 102 . Once the placement position of the partition device 102 is fixed, the partition pattern is determined accordingly. In addition, the partition device 102 is in surface contact with the optical element board 104 , and when the adjacent backlight sources 106 are all turned on, dark lines are likely to be generated above the partitions of the partition device 102 . If two adjacent backlight sources are respectively in a bright state and a dark state, an unnatural light-dark border will be formed at their contact positions.

In order to solve the above-mentioned defects in the prior art, the present invention provides a relatively flexible partition device. FIG. 2A shows a schematic structural diagram of a partition device for a direct-lit backlight module according to an embodiment of the present invention. Figure 2B shows another view of the spacer of Figure 2A.

Referring to FIG. 2A and FIG. 2B , the partition device of the present invention is suitable for realizing combined multiple local dimming in a direct-lit backlight module. The dividing device includes a supporting column 302 , a rotating motor 304 and a partition 306 . The partition sheet 306 is straight and has a certain thickness. Wherein, the support column 302 is in point contact with the lower surface of the optical element board of the direct type backlight module, and is used to support the optical element board. Preferably, the respective surfaces of the support column 302 , the rotating motor 304 and the partition plate 306 of the partitioning device are sprayed with high reflectivity materials, and when the light emitted from the backlight reaches these parts of the partitioning device, it is reflected on the surface.

In addition, the support column 302 can be designed as a cone or a regular pyramid. For example, when the support column 302 is a conical structure, the light emitted by the backlight cannot be incident on the contact portion between the optical element board and the support column 302, so the top surface of the support column 302 in contact with the optical element board has a smaller cut surface Diameter, this will undoubtedly help to reduce the situation where the top of the support column 302 blocks the incident light. Because of this, the supporting pillar 302 is in point contact with the optical element board, and no dark lines will appear on the optical element board when the adjacent backlight sources are all turned on. In addition, even if there is a relative displacement between the supporting column 302 and the optical element board of the present invention, the optical element board can be prevented from being scratched because point contact is used instead of the existing surface contact method.

The rotation motor 304 is located under the support column 302 and can rotate around the corresponding backlight. The partition plate 306 is fixedly connected with the rotary motor 304 . In this way, when the rotating motor 304 moves, it can drive the partition plate 306 fixedly connected with it to rotate around the backlight to form an independent area, which can be illuminated according to the screen partitions of the LCD screen.

In a specific embodiment, the partition device further includes a fixing part. The fixing part has a base 308 and two hooks 310 integrally formed with the base 308 , as shown in FIG. 2B . The partition device is fixed to the bottom plate of the direct type backlight module by the hook 310 . It will be described in detail below. In addition, the rotating motor 304 is a cylinder, the base 308 is a disk, and the diameter of the disk 308 is larger than the diameter of the bottom surface of the cylinder 304 .

FIG. 3 shows a schematic diagram of two adjacent backlight sources being on when the partition device in FIG. 2A is assembled into a direct-type backlight module. FIG. 4 shows a schematic diagram of two adjacent backlights being on and off respectively when the partition device in FIG. 2A is assembled to a direct-lit backlight module.

Referring to FIG. 3 , the direct type backlight module includes a bottom plate 303 , a plurality of backlight sources (such as P1 , P2 ) and an optical element board 301 . For example, the optical element board 301 is a diffuser. The backlight source P1 is located between the base plate 303 and the optical element plate 301 . Moreover, the direct-lit backlight module further includes a plurality of partitions, for example, the partitions corresponding to the backlight P1 are placed around it, and the partitions corresponding to the backlight P2 are also placed around it. In this embodiment, the backlight source P1 and the backlight source P2 are both on. The height of the support column 302 is identified by the symbol d.

In FIG. 3 , the bottom plate 303 also includes a through hole H. As shown in FIG. The base 308 and the hook 310 of the fixing portion are respectively located on opposite sides of the bottom plate 303 , that is, the base 308 is on the upper side of the bottom plate 303 , and the hook 310 is on the lower side of the bottom plate 303 . The hook 310 passes through the through hole H of the bottom plate 303 , so that the bottom plate 303 is inserted into the receiving space formed by the base 308 and the hook 310 , thereby fixing the partition device to the bottom plate 303 . Preferably, the hook 310 can be made of elastic material. When the hook 310 passes through the through hole H, the hook 310 is in an elastic compression state. When the hook 310 passes through and extends out of the through hole H, the hook 310 returned to its natural state.

According to a specific embodiment, the direct type backlight module further includes a reflective sheet 305 . The reflection sheet 305 is located above the bottom plate 303, and has an opening at the corresponding position of the through hole H, and the fixing part of the partition device passes through the opening and the through hole H in turn, so as to prevent the light emitted from the backlight source P1 or P2 from escaping.

Similarly, in FIG. 4 , the backlight source P1 is in the on state and the backlight source P2 is in the off state. However, it can be seen from the propagation path of the light emitted from the backlight source P1 that a part of the light rays are refracted inside the optical element board 301 and enter above the backlight source P2. In this way, the direct-lit backlight module of the present invention can blur the unnatural boundary between light and dark through the separating device, thereby reducing light leakage.

FIGS. 5( a ) to 5 ( c ) show schematic diagrams of regional dimming by rotating partition plates 306 of different shapes in an alternative embodiment of the partition device in FIG. 2A .

In Fig. 5(a), the cross-sectional shape of the partition plate is semicircular. When the rotating motor 304 drives the partition plate 306 to rotate to a certain position, the effect of local dimming can be achieved by controlling the brightness of each backlight. Yes, the circular area in the middle is dark, and the circular areas on the left and right are bright. In Fig. 5(b), the cross-sectional shape of the partition sheet is an arc shape less than 180 degrees. Since the cross-sectional shape of the partition sheet changes, when the partition sheet 306 rotates with the rotary motor 304, the brightness of each backlight will Dark control, the effect of regional dimming is adjusted so that the oval areas on the left, middle and right are all bright. In addition, the arc-shaped partition sheet 306 in Fig. 5(b) can also be rotated at a certain angle, and the light and dark distribution of each backlight can be changed, so that the shape of the dimming area in Fig. 5(c) is different from that in Fig. 5(b ) The shape of the dimming area.

FIG. 6( a ) and FIG. 6( b ) show schematic diagrams of different backlight scanning patterns formed by the direct-lit backlight module of the present invention through the partition device in FIG. 2A .

In addition, by using the separating device of the direct type backlight module of the present invention, different backlight scanning patterns can be realized, thereby improving the contrast of the display screen. For example, in Figure 6(a), the bright and dark states of the backlight at different positions are alternately distributed, while in Figure 6(b), the bright and dark states of the backlight are regularly distributed according to the position of the row or column.

Using the partition device of the present invention and the direct type backlight module comprising the partition device, the backlight source is located between the bottom plate and the optical element board, each partition device is arranged around the corresponding backlight source, and the partition device includes a support column, a rotation motor And the partition sheet, the support column is in point contact with the lower surface of the optical element board, the rotation motor is located under the support column, the partition sheet is fixedly connected to the rotation motor, and the rotation motor drives the partition sheet to rotate around the corresponding backlight to form an independent The area is illuminated in accordance with the screen partitions of the LCD screen to improve the contrast of the screen. Compared with the prior art, the direct-lit backlight module of the present invention can eliminate the dark line (darkline) on the contact surface between the existing partition board and the optical element board, and can blur the unnatural boundary between light and shade in the current module, reducing the light leaks. In addition, the supporting column and the optical element board of the present invention are in point contact, so the relative displacement between the supporting column and the optical element board can be avoided to cause scratches.

Hereinbefore, specific embodiments of the present invention have been described with reference to the accompanying drawings. However, those skilled in the art can understand that without departing from the spirit and scope of the present invention, various changes and substitutions can be made to the specific embodiments of the present invention. These changes and substitutions all fall within the scope defined by the claims of the present invention.

Claims (10)

1. A direct type backlight module, comprising a bottom plate, a plurality of backlight sources and an optical element plate, wherein the backlight sources are located between the bottom plate and the optical element plate, characterized in that the direct type backlight module further comprises a plurality of separating devices, each separating device is arranged around the corresponding backlight source, the separating devices comprise:

a support column, which is in point contact with the lower surface of the optical element plate, for supporting the optical element plate;

a rotary motor located below the support column; and

a partition plate fixedly connected with the rotary motor,

the rotating motor drives the partition sheet to rotate around the backlight source, so that an independent area is formed to be matched with the image partition lighting of the liquid crystal screen.

2. The direct type backlight module according to claim 1, wherein the separating device further comprises a fixing portion, and the bottom plate further comprises a through hole, and the fixing portion penetrates through the through hole to fix the separating device to the bottom plate.

3. The direct-type backlight module as claimed in claim 2, wherein the fixing portion has a base and two hooks integrally formed with the base, the base and the hooks are respectively located at two opposite sides of the bottom plate, and the bottom plate is embedded in the receiving space formed by the base and the hooks.

4. The direct type backlight module according to claim 3, wherein the rotary motor is a cylinder, the base is a disk, and the diameter of the disk is larger than the diameter of the bottom surface of the cylinder.

5. The direct type backlight module according to claim 2, further comprising a reflective sheet disposed above the bottom plate, wherein the reflective sheet has an opening at a position corresponding to the through hole, and the fixing portion of the partition is sequentially inserted through the opening and the through hole.

6. The direct type backlight module according to claim 1, wherein the optical device plate is a diffuser plate.

7. The direct type backlight module according to claim 1, wherein the support columns of the spacers, the rotation motor and the partition plates are coated with a material having high reflectivity on their respective surfaces.

8. The direct type backlight module according to claim 1, wherein the support columns are cones or regular rectangular pyramids.

9. A separating device for a direct-type backlight module, the direct-type backlight module comprising a bottom plate, a plurality of backlight sources and an optical element plate, the backlight sources being located between the bottom plate and the optical element plate, the separating device being disposed around the corresponding backlight sources, comprising:

a support column, which is in point contact with the lower surface of the optical element plate, for supporting the optical element plate;

a rotary motor located below the support column; and

a partition plate fixedly connected with the rotary motor,

the rotating motor drives the partition sheet to rotate around the backlight source, so that an independent area is formed to be matched with the image partition lighting of the liquid crystal screen.

10. The spacer for direct-type backlight module according to claim 9, wherein the spacer further comprises a fixing portion having a base and two hooks integrally formed with the base, the bottom plate further comprises a through hole,

the base and the clamping hooks are respectively positioned on two opposite sides of the bottom plate, and the clamping hooks penetrate through the through holes of the bottom plate, so that the bottom plate is embedded in the accommodating space formed by the base and the clamping hooks, and the separating device is fixed on the bottom plate.