CN104075187B - Backlight module and display device - Google Patents

Abstract

The backlight module and the display device of the present invention, wherein the backlight module includes a light guide plate and a plurality of point light sources arranged at intervals on one side of the light guide plate, and the light guide plate includes a front surface for guiding light to the panel and a front surface opposite to the front surface. The back side of the light guide plate is provided with a first shading element on the front side of the light guide plate. On the side of the first shading element facing the front of the light guide plate, multiple sets of dot structures are arranged at intervals. The dot structures include a plurality of unit points. The multiple sets of dot structures are respectively Opposite the point light sources one by one, the gaps between the point structures are opposite to the gaps between the point light sources. The display device of the present invention includes the backlight module of the present invention. The technical solution of the present invention adds a first shading element in the backlight structure to selectively absorb or scatter and reflect a relatively strong part of the light emitted by the point light source to the B area on the light guide plate, so as to reduce the difference between the A area and the light source on the light guide plate. The difference in the ratio of light in the area B on the light guide plate prevents the phenomenon of alternate light and dark spots on the light guide plate from occurring.

Description

Backlight module and display device

technical field

The invention relates to a device for controlling an independent light source, in particular to a backlight module and a display device.

Background technique

The backlight module is one of the important components of the liquid crystal display. Since the liquid crystal itself does not emit light, the function of the backlight module is to supply sufficient brightness and evenly distributed light source, so that the liquid crystal display can display images normally. At present, the display technology of liquid crystal display has become mature, especially in the design of the backlight module. In addition to being used in liquid crystal display devices such as liquid crystal displays and liquid crystal televisions, backlight modules can also provide light sources for display devices such as digital photo frames, electronic paper, and mobile phones.

The backlight module is divided into a side-type backlight module and a direct-type backlight module according to the position of the light source. Among them, the currently used side-entry backlight modules often use black and black tape (both front and back are black) or black and white tape (black on the front and white on the back) to optically block the light in front of the LED. LED is similar to a point light source. The light density of the LED is inconsistent with the light density of the space between the LEDs, so there will be a hotspot (light spot) phenomenon on the light guide plate. The amount of light is increasing, and it is becoming more and more difficult to achieve uniform distribution of light only through the dots on the light guide plate.

Contents of the invention

The purpose of the present invention is to provide a backlight module and a display device which can overcome the inconsistency of the light density in the space between the point light sources and prevent the occurrence of alternate light and dark spots on the light guide plate.

The backlight module of the present invention includes a light guide plate and a plurality of point light sources arranged at intervals on one side of the light guide plate, and the light guide plate includes a front surface for guiding light to a panel and a back surface opposite to the front surface , the front side of the light guide plate is provided with a first shading element, and the side of the first shading element facing the front of the light guide plate is provided with multiple groups of dot structures at intervals, and the dot structures include a plurality of unit points , the multiple groups of point structures are respectively opposed to the point light sources one by one, and the gaps between the point structures are opposite to the gaps between the point light sources.

In the backlight module of the present invention, the first shading element includes a first side close to the point light source and a second side opposite to the first side, and the multiple groups of point structures are along the arrangement direction of the point light source arranged between the first side and the second side.

In the backlight module of the present invention, the dot structures are located on the first light-shielding element in a region corresponding to the light guide plate.

In the backlight module of the present invention, the size of the plurality of unit dots in each group of dot structures decreases gradually along the direction from the first side to the second side.

In the backlight module of the present invention, the unit points of each group of point structures are arranged to form a trapezoid close to the first side and a cone connected to the trapezoid close to the second side, and the tapered The apex of the cone points to the second side, and the short side of the trapezoid faces the first side.

In the backlight module of the present invention, a plurality of unit points of each group of point structures are arranged along the extension direction of the first side to form a plurality of unit queues, and the plurality of unit queues are arranged equidistantly, and each of the unit queues One said unit point and the corresponding unit points in the adjacent unit queues on both sides are on a straight line perpendicular to the first side, and the size of the multiple unit points in the unit queue is along the point structure The central axis decreases symmetrically to both sides.

In the backlight module of the present invention, wherein the material of the first shading element is polyethylene terephthalate, the first shading element is transparent, and the light refractive index of the first shading element is less than 1.5. .

In the backlight module of the present invention, the unit dots are black or white.

In the backlight module of the present invention, the unit points are rectangles, circles, ellipses, triangles or polygons.

In the backlight module of the present invention, the first side of the first light shielding element is located in the area corresponding to the point light source, and the second side of the first light shielding element is located in the area corresponding to the light guide plate.

In the backlight module of the present invention, a second shading element is provided on the outer side of the first shading element facing the panel.

The display device of the present invention includes the backlight module of the present invention.

In the technical solution of the present invention, by adding the first shading element in the backlight structure to selectively absorb or scatter and reflect a relatively strong part of the light emitted by the point light source to the B area on the light guide plate, the A area on the light guide plate can be reduced. The difference in the proportion of light from the B area on the light guide plate solves the problem of inconsistency between the light density of the point light source and the light density of the space between the point light sources, and prevents the occurrence of alternate light and dark spots on the light guide plate.

Description of drawings

Fig. 1 is the structural representation of an embodiment of the backlight module of the present invention;

FIG. 2 is a schematic structural view of another embodiment of the backlight module of the present invention;

3 is a schematic structural view of the first light-shielding element in the backlight module of the present invention, and also shows the positional relationship and functional relationship between the first light-shielding element, the light guide plate, and the point light source.

detailed description

The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments, so that those skilled in the art can better understand the present invention and implement it, but the examples given are not intended to limit the present invention.

In the present invention, an independent first light-shielding element is added to the existing backlight structure, and the first light-shielding element can realize selective light-shielding (absorption, scattering).

As shown in Fig. 1 and Fig. 3, the embodiment of the backlight module of the present invention includes a light guide plate 1 and a plurality of point light sources 2 arranged at intervals on one side of the light guide plate 1, and the light guide plate 1 includes a The front side 10 of the light guide and the back side 20 opposite to the front side 10 are provided with a first light shielding element 3 on the side of the front side 10 of the light guide plate. On the side of the front surface 10 of the first light-shielding element 3 facing the light guide plate, there are multiple groups of point structures 4 arranged at intervals. The point structures 4 include a plurality of unit points 5. The multiple groups of point structures 4 are respectively opposed to the point light sources 2 one by one. The point structures The gap between 4 is opposite to the gap between point light sources 2.

In FIG. 1 , the area A corresponding to the point light source 2 has a relatively high light density, and the area B corresponding to the gap between the point light source 2 and the point light source 2 has a low light density. Through the point structure 4, the first shading element 3 can achieve Part of the light emitted from area A (the front of the LED) is reflected, scattered to area B (the area between the LEDs) or absorbed to prevent defects such as light spots in the backlight structure.

In the embodiment of the backlight module of the present invention, the first shading element 3 includes a first side 31 close to the point light source 2 and a second side 32 opposite to the first side 31, and the multiple groups of point structures 4 are along the side of the point light source 2. The arrangement direction is arranged between the first side 31 and the second side 32 .

In the embodiment of the backlight module of the present invention, the dot structures 4 are located on the first light-shielding element 3 in the area corresponding to the light guide plate 1, specifically, the dot structures 4 are all located on the first light-shielding element 3 and In the area opposite to the front surface 10 of the light guide plate 1 .

In the embodiment of the backlight module of the present invention, the size of the plurality of unit dots 5 of each group of dot structures 4 decreases gradually along the direction from the first side 31 to the second side 32 .

In the embodiment of the backlight module of the present invention, wherein the unit points 5 of each group of point structures 4 are arranged to form a trapezoid near the first side 31 and a conical shape connected with the trapezoid near the second side 32, the apex of the cone points to The second side 32 , the short side of the trapezoid faces the first side 31 .

In the embodiment of the backlight module of the present invention, wherein, a plurality of unit points 5 of each group of point structures 4 are arranged along the extension direction of the first side 31 to form a plurality of unit queues 40, and the plurality of unit queues 40 are arranged equidistantly, and the unit queues 40 Each unit point 5 and the corresponding unit points 5 in the adjacent unit queues on both sides are on a straight line perpendicular to the first side 31, and the size of multiple unit points 5 in the unit queue 40 is along the center of the point structure 4. The axis decreases symmetrically to both sides.

In the embodiment of the backlight module of the present invention, the material of the first shading element 3 is polyethylene terephthalate, the first shading element is transparent, and the refractive index of the first shading element 3 is less than 1.5.

In an embodiment of the backlight module of the present invention, the unit dots 5 are black or white.

In an embodiment of the backlight module of the present invention, the unit point 5 is in the shape of a rectangle, a circle, an ellipse, a triangle or a polygon.

In the embodiment of the backlight module of the present invention, the first side 31 of the first shading element 3 is located in the area corresponding to the point light source 2 , and the second side 32 of the first shading element is located in the area corresponding to the light guide plate 1 . Specifically, the second edge 32 is located in a region opposite to the front surface 10 of the light guide plate 1 .

In the embodiment of the backlight module of the present invention, the second shading element 6 is provided on the outside of the side of the first shading element 3 facing the panel. The second light-shielding element 6 is a black-and-black adhesive tape (both front and back are black) or black-and-white adhesive tape (the front is black and the back is white).

In the embodiment of the backlight module of the present invention, an optical film 7 is arranged between the first shading element 3 and the light guide plate 1, a circuit board 9 is arranged between the first shading element 3 and the point light source 2, and the light guide plate 1 A backboard 8 is provided on the back side.

As shown in FIG. 2 , in another embodiment of the backlight module of the present invention, the first light shielding element 3 is directly attached to the light guide plate 1 .

The display device of the present invention includes the backlight module of the present invention.

The embodiment of the first shading element of the backlight module of the present invention is to print ink materials with reflection, scattering and light absorption functions on transparent materials such as low light refractive index (n<1.5) PET, such as resin plus pigment plus Diffuser, wherein the pigment is SiO and TiO ₂ with reflective effect.

The first shading element of the backlight module of the present invention is arranged at a relatively necessary position in front of the point light source, and selectively absorbs or scatters and reflects a relatively strong part of the light emitted by the point light source (on the light guide plate) through the micro-dot type point structure 4. The A area) light to the B area on the light guide plate can reduce the light ratio difference between the A area on the light guide plate and the B area on the light guide plate, and can effectively reduce the incidence of optical defects such as light spots in the backlight structure.

The technical solution of the present invention adjusts the optical path by adding the first shading element to the backlight structure (partially and selectively reflects and scatters excess light in the A area to the B area to achieve the purpose of uniform light distribution).

In the backlight module of the present invention, the size, density distribution and arrangement sequence of the unit dots of the dot structure of the first shading element can be adjusted and designed according to the specific form of the backlight structure.

The above is only a preferred embodiment of the present invention, it should be pointed out that for those of ordinary skill in the art, without departing from the principle of the present invention, some improvements and modifications can also be made, and these improvements and modifications should also be It is regarded as the protection scope of the present invention.

Claims (10)

1. A backlight module, comprising a light guide plate and a plurality of point light sources arranged at intervals on one side of the light guide plate, the light guide plate includes a front for guiding light to a panel and a front opposite to the front The back side is characterized in that a first shading element is provided on the front side of the light guide plate, and multiple groups of dot structures are arranged at intervals on the side of the first shading element facing the front of the light guide plate, and the dot structures It includes a plurality of unit points, the multiple groups of point structures are respectively opposed to the point light sources one by one, and the gaps between the point structures are opposite to the gaps between the point light sources; The first shading element includes a first side close to the point light source and a second side opposite to the first side, and multiple groups of point structures are arranged on the first side and the second side along the arrangement direction of the point light source. between the second side; The size of the multiple unit points of each group of point structures decreases along the direction from the first side to the second side. 2 . The backlight module according to claim 1 , wherein the dot structures are located in a region corresponding to the light guide plate on the first light shielding element. 3 . 3. The backlight module according to claim 1, wherein the unit points of each group of point structures are arranged to form a trapezoid close to the first side and a trapezoid connected to the trapezoid close to the second side. Conical, the apex of the cone points to the second side, and the short side of the trapezoid faces the first side. 4. The backlight module according to claim 3, wherein a plurality of unit points of each group of point structures are arranged along the extending direction of the first side to form a plurality of unit queues, and the plurality of unit queues are arranged equidistantly , each of the unit points in the unit queue is on a straight line perpendicular to the first side with the corresponding unit points in the adjacent unit queues on both sides, and a plurality of the unit points in the unit queue The size decreases symmetrically to both sides along the central axis of the dot structure. 5. The backlight module according to claim 1, wherein the material of the first shading element is polyethylene terephthalate, the first shading element is transparent, and the first shading element is transparent. The light refraction index of the shading element is less than 1.5. 6. The backlight module according to claim 1, wherein the unit dots are black or white. 7. The backlight module according to claim 1, wherein the unit point is a rectangle, a circle, an ellipse, a triangle or a polygon. 8. The backlight module according to claim 1, wherein the first side of the first shading element is located in the area corresponding to the point light source, and the second side of the first shading element is located in the In the area corresponding to the light guide plate. 9 . The backlight module according to claim 1 , wherein a second shading element is provided on an outer side of the first shading element facing the panel. 10. A display device, comprising the backlight module according to any one of claims 1-9.