CN113985653B

CN113985653B - Light-emitting element, backlight source, backlight module and display device

Info

Publication number: CN113985653B
Application number: CN202111224271.1A
Authority: CN
Inventors: 王耀东; 郑仰利; 张晓萍; 任健; 张罗; 刘芳怡; 印思琪; 高晓娟; 周震国
Original assignee: BOE Technology Group Co Ltd; Beijing BOE Display Technology Co Ltd
Current assignee: BOE Technology Group Co Ltd; Beijing BOE Display Technology Co Ltd
Priority date: 2021-10-20
Filing date: 2021-10-20
Publication date: 2023-10-20
Anticipated expiration: 2041-10-20
Also published as: CN113985653A

Abstract

The application discloses a light-emitting element, a backlight source, a backlight module and a display device, wherein the light-emitting element comprises: a bracket; the chip is arranged on the bracket; the fluorescent glue is coated on the chip and forms a concave surface shape in the light emergent direction of the chip, and a convex lens is arranged in the concave surface shape. The luminous element provided by the embodiment of the application adopts the fluorescent glue as a concave shape and is provided with the convex lens in the light emitting direction, so that the limit of the luminous angle of the luminous element is 147.42 degrees; through the mode of increase luminous angle, reduce the frame greatly, improve product competitiveness.

Description

Light-emitting element, backlight source, backlight module and display device

Technical Field

The present application relates generally to the field of display technologies, and in particular, to a light emitting device, a backlight source, a backlight module and a display device.

Background

Currently, in a side-entry backlight module, the light type of an LED approximates a lambertian body, and the light emission angle of the LED is 120 ° (the maximum light emission angle can be proved by a surface light source theory, and the maximum light emission angle actually measured by the device is about 115 ° -120 °). LED emission angles are also known as power angles, and typically we use half-power angles, i.e., angles at 50% emission intensity.

Because the light emitting angle of the LED is fixed, when the light intensity of the LED at the light incident side is overlapped and mixed, if the light mixing distance is insufficient, a phenomenon of uneven brightness appears in the edge area of the LGP, and the phenomenon is called a Hotspot lamp shadow phenomenon. The larger the light mixing distance is, the larger the black edge area required by the backlight module is, and the frame cannot be narrowed.

Disclosure of Invention

In view of the above-mentioned drawbacks or shortcomings of the prior art, it is desirable to provide a light emitting element, a backlight module and a display device, which can increase the light emitting angle of the LED and greatly reduce the frame value of the display device.

In a first aspect, the present application provides a light emitting element comprising:

a bracket;

the chip is arranged on the bracket;

the fluorescent glue is coated on the chip and forms a concave surface shape in the light emergent direction of the chip, and a convex lens is arranged in the concave surface shape.

Optionally, the convex lens is formed by dispensing fluorescent glue.

Preferably, the light emitting angle of the chip is 90 ° to 120 °, and the light emitting angle of the light emitting element is 106.66 ° to 147.42 °.

Optionally, the refractive index of the fluorescent glue is 1.53-1.57.

In a second aspect, the present application provides a backlight comprising a light bar having a plurality of light emitting elements as described above arranged in an array thereon.

Optionally, be provided with the lamp strip on the lamp strip and glue, the lamp strip glues including the first surface and the second surface that the symmetry set up, first surface with the second surface is black, be provided with a plurality of white pieces of array setting on first surface or the second surface.

Further, the array direction of the white block is the same as the array direction of the light emitting elements, a first interval is arranged between two adjacent light emitting elements, and the white block is arranged at the first interval.

Optionally, the white block is horn-shaped, and the white block includes a first edge near the light emitting element and a second edge facing away from the light emitting element, and the length of the second edge is greater than the length of the first edge.

Preferably, the length of the first side is not less than the length of the first pitch; the second side overlaps the light emitting element by a length not exceeding 1/6 of the length of the light emitting element.

Optionally, the white block is made of PET material, and the white block is adhered to the first surface.

Optionally, the adjacent three light emitting elements are a light group, and a plurality of light groups are arranged on the light bar in an array, wherein the plurality of light groups form three light strings arranged in parallel, and three light emitting elements in each light group are respectively located in different light strings.

Preferably, the light bar includes three layers of wiring regions, each layer of wiring region corresponds to the wiring of each light emitting element in one of the light strings.

In a third aspect, the present application provides a backlight module, including a light guide plate and the backlight source as described above located at one side of the light guide plate.

Further, the light guide plate includes an array of concave inner surfaces for accommodating the convex lenses of the light emitting elements.

Optionally, the concave surface is provided with an irregular structure, the irregular structure includes a plurality of irregular saw-tooth shapes, and the density of the saw-tooth shapes gradually increases from the center of the concave surface to two ends.

Optionally, a gap is installed between the concave surface and the convex lens surface.

Further, the light guide plate comprises a composite film layer arranged on the light guide plate, the composite film layer extends from the light guide plate to the position of the light emitting element, and the composite film layer at least covers part of the light emitting element.

Optionally, the composite film layer comprises a composite prism layer and a diffusion layer which are arranged in a stacked manner, wherein,

the composite prism layer comprises at least one prism array layer, wherein the prism array layer comprises a first substrate layer and a plurality of prism bodies arranged on the first substrate layer in an array manner;

the diffusion layer comprises a second substrate layer and a diffusion particle layer arranged on the second substrate layer, and the diffusion layer is arranged on one side close to the light guide plate.

Optionally, the composite film layer is provided with a plurality of pre-slit in a lap joint area covering the light emitting element.

In a fourth aspect, the present application provides a display device, including a display panel, a frame, and a backlight module as described above.

Preferably, the distance between the frame and the visible area of the display panel is 1.68-2.1 mm, and the distance between the display area of the display panel and the visible area is 0.2-0.25 mm.

The technical scheme provided by the embodiment of the application can comprise the following beneficial effects:

the luminous element provided by the embodiment of the application adopts the fluorescent glue as a concave shape and is provided with the convex lens in the light emitting direction, so that the limit of the luminous angle of the luminous element is 147.42 degrees; through the mode of increase luminous angle, reduce the frame greatly, improve product competitiveness.

Drawings

Other features, objects and advantages of the present application will become more apparent upon reading of the detailed description of non-limiting embodiments, made with reference to the accompanying drawings in which:

fig. 1 is a schematic structural diagram of a light emitting device according to an embodiment of the present application;

fig. 2 is a schematic structural diagram of another light emitting device according to an embodiment of the present application;

FIG. 3 is a schematic diagram of the optical path of light propagating between two interfaces of different refractive indices;

FIG. 4 is a schematic view of a light-emitting device according to an embodiment of the present application in a concave arc and horizontal state;

FIG. 5 is a schematic diagram of a light path of a light emitting device according to an embodiment of the present application;

FIG. 6 is a schematic diagram of a maximum light emitting angle of a light emitting device according to an embodiment of the present application;

fig. 7 is a schematic structural diagram of a backlight according to an embodiment of the present application;

fig. 8 is a schematic structural diagram of a light bar adhesive according to an embodiment of the present application;

fig. 9 is a schematic diagram of a circuit diagram of a light emitting element according to an embodiment of the present application;

FIG. 10 is a cross-sectional view of an FPC routing area provided by an embodiment of the present application;

fig. 11 is a schematic structural diagram of a backlight module according to an embodiment of the application;

fig. 12 is a schematic diagram of a light guide plate and a light emitting element at a matching position according to an embodiment of the present application;

FIG. 13 is a schematic structural diagram of a composite membrane layer according to an embodiment of the present application;

FIG. 14 is a schematic view of a composite film layer in a lap joint area according to an embodiment of the present application;

fig. 15 is a schematic diagram of a positional relationship of a backlight module according to an embodiment of the application;

fig. 16 is a schematic structural diagram of a display device according to an embodiment of the present application;

FIG. 17 is a diagram showing a relationship between key size matches on the socket side of a display module according to an embodiment of the present application;

fig. 18 is a schematic diagram of an optical relationship of a backlight source on a socket side of a display module according to an embodiment of the application.

Detailed Description

The application is described in further detail below with reference to the drawings and examples. It is to be understood that the specific embodiments described herein are merely illustrative of the application and are not limiting of the application. It should be noted that, for convenience of description, only the portions related to the application are shown in the drawings.

It should be noted that, without conflict, the embodiments of the present application and features of the embodiments may be combined with each other. The application will be described in detail below with reference to the drawings in connection with embodiments.

Referring to fig. 1-2, the present application provides a light emitting device, comprising:

a bracket 1;

a chip 2, which is arranged on the bracket;

and the fluorescent glue 3 is coated on the chip and forms a concave surface shape in the light emergent direction of the chip, and a convex lens 4 is arranged in the concave surface shape.

In the embodiment of the application, the light-emitting element is an LED light-emitting element, and the light-emitting angle of the LED is increased on the premise of not changing the package by adopting the form of the convex lens on the light-emitting side of the LED lamp. The frame of the display panel can be effectively reduced when the display panel is applied to the display panel.

According to the law of refraction, when light propagates in two media, as shown in fig. 3, an incident light d1 irradiates from a first interface X to a second interface Y, and at the boundary position between the first interface X and the second interface Y, the incident light d1 'is divided into a part of reflected light d 1', and another part of refracted light d2, θ ₁ For the angle theta between the incident ray and the normal ₁ ' is the angle between the reflected ray and the normal, θ ₂ Is the included angle between the refracted ray and the normal, wherein theta ₁ And theta ₁ ' the angles are the same, when light is incident from the optically sparse medium into the optically dense medium, θ ₂ Is smaller than theta ₁ And vice versa.

When light is emitted from a medium with optical density (i.e. light with a large refractive index in the medium) to an interface of a medium with optical hydrophobicity (i.e. light with a small refractive index in the medium), all the light is reflected back into the original medium. When light enters the photophobic medium from the photophobic medium, the light is refracted away from the normal. When the angle of incidence θ, which is called the critical angle, increases to a certain level (e-ray in the figure), the refracted ray proceeds along the surface, i.e., the angle of refraction is 90 °. If the incident angle is greater than the critical angle, there is no refraction and all the light rays are reflected back to the optical dense medium, a phenomenon known as total reflection. From the above, light is emitted from the optically dense medium to the optically sparse medium, and the incident angle is smaller than the refraction angle.

As the light emitted by the chip is reflected and refracted at the glue/air interface, the energy of the reflected light is increased and the energy of the refracted light is reduced along with the increase of the incident angle, when the total reflection angle is reached, the energy of the reflected light is maximum, and no refracted light exists, so that the luminous intensity of the LED is the highest at the center, and the angular intensity of the two sides is gradually reduced.

Fig. 4 shows the light condition at the concave arc and the interface between the level and the air, the glue dispensing plane is concave glue with the LED glue surface as the horizontal plane, the light emitted by the same chip is larger in the center of the concave arc than when the glue surface is horizontal, the light is easier to reflect into the glue, and the incident angle is larger as the light goes to two sides. Fig. 5 shows the light condition at the interface between the convex arc and the air, and the light emitted by the same chip has smaller emergent angle at the center of the convex arc than when the glue surface is horizontal, so that the light is more easily refracted into the air, and meanwhile, the incident angle is larger as the light goes towards two sides. Assuming that the incident angle is 45 degrees, the concave arc and the flat arc design lead the LED light to generate total reflection (the refractive index of the LED dispensing glue is 1.53-1.57), the LED cannot be emitted, and the maximum luminous angle of the LED is further influenced.

In the embodiment of the application, the luminous angle of the chip is 90-120 degrees, and the luminous angle of the LED lamp is 106.66-147.42 degrees. Preferably, as shown in fig. 6, when the half angle of the light emission of the LED chip designed by the convex adhesive reaches 60 °, the angle of the light emitted by the LED can reach 73.71 °, and the angle of the light emission of the LED can reach 147.42 °.

It should be noted that, in the embodiment of the present application, the light emitting half angle of the chip is defined as half of the light emitting angle, that is, the included angle between the light emitting ray and the center line of the chip. In the embodiment of the application, the refractive index of the fluorescent glue is 1.53-1.57, and the calculation of the light emitting angles of the light rays corresponding to different chip light emitting half angles in the concave arc, horizontal arc and convex arc is illustrated in the following table 1 by taking the refractive index of the fluorescent glue as 1.53 as an exemplary illustration.

TABLE 1

Project	Concave arc	Concave arc	Horizontal level	Horizontal level	Convex arc	Convex arc	Limit of convex arc
								Chip luminous half angle	24	45	24	45	24	45	60
Included angle of light and horizontal plane	66	45	66	45	66	45	30
								Glue normal and chip light-emitting surface included angle	87	68	90	90	101	120	127
Incidence angle A (angle with normal)	27	67	24	45	13	15	23
								Radian (A)	0.47	1.17	0.42	0.79	0.23	0.26	0.40
sin(A)	0.45	0.92	0.41	0.71	0.22	0.26	0.39
								sin (A) n1 (glue refractive index 1.53)	0.69	1.41	0.62	1.08	0.34	0.40	0.60
sin (B) n2 (air refractive index 1.0)	0.69	1.41	0.62	1.08	0.34	0.40	0.60
								Exit angle (B)	0.77	#NUM！	0.67	#NUM！	0.35	0.41	0.64
Angle of emergent light (B) relative to normal	44.00	Total reflection occurs without refraction of light	38.48	Total reflection occurs without refraction of light	20.13	23.33	36.71
								Angle of emergent light (B) relative to the chip center line	41.00	LED maximum lighting angle limitation	38.48	LED maximum lighting angle limitation	31.13	53.33	73.71

In the embodiment of the application, the LED is adopted to design the lower frame to be 2.1mm by increasing the LED light-emitting angle, and the module 2.1mm frame can realize the productization by verifying the AP value and the cross light and adding corresponding light efficiency optimization measures.

In one embodiment of the present application, the convex lens is formed by dispensing fluorescent glue. In other embodiments, the convex lens may further comprise a glass or plastic lens, and the convex lens is fixed by fluorescent glue. Wherein the phosphor paste may be prepared from an alternating material doped with phosphor particles, and the material of the phosphor and the fluorescence are not limited in the present application.

The silica gel is taken as a substrate, the silica gel material is a light-permeable material, the refractive index of the silica gel material is 1.4-1.6, and after fluorescent powder particles are doped in the light-permeable substrate, the refractive index of the fluorescent gel can be still adjusted to be 1.53-1.57. And the adhesive has certain viscosity, and is convenient to fix with the chip and the convex lens.

As shown in fig. 7, the present application further provides a backlight source, which includes a light bar 10, and a plurality of light emitting elements 20 as described above are disposed on the light bar in an array.

The light bar is provided with a light bar glue 30, the light bar glue 30 is used for attaching the light bar to the light guide plate, and in the embodiment of the application, the surface of the light bar glue 30 is provided with viscosity or the body of the light bar glue 30 is made of a viscous material; the light bar glue 30 is disposed on the lower surface of the light guide plate for fixing the backlight. Since the partial area of the light guide plate, which is close to the light emitting element 20, is a light mixing area, in the light mixing area, the light emitting element 20 on the lamp panel has a pitch, so that the brightness is higher in the light emitting range corresponding to the light emitting element 20, and the brightness is lower in the range corresponding to the pitch, thereby generating the bad phenomenon of uneven display brightness.

As shown in fig. 8, the light bar glue 30 includes a first surface and a second surface that are symmetrically disposed, the first surface and the second surface are both black, and a plurality of white blocks 40 are disposed on the first surface or the second surface in an array.

It should be noted that, in the embodiments of the present application, the first surface is a side surface close to the light guide plate, and the second surface is a side surface facing away from the light guide plate, and in some embodiments, the first surface and the second surface may be interchanged. In the embodiment of the application, the first surface is taken as a surface provided with the white block and the LED lamp as an exemplary illustration.

In the embodiment of the present application, the array direction of the white block 40 is the same as the array direction of the light emitting elements 20, a first space 50 is provided between two adjacent light emitting elements 20, and the white block 40 is disposed at the first space 50.

Wherein the white block 40 is horn-shaped, the white block 40 includes a first side 401 near the light emitting element 20 and a second side 402 facing away from the light emitting element 20, and the length of the second side 402 is greater than the length of the first side 401. When the first edge 401 is arranged, the length of the first edge is not smaller than the length of the first interval; the second edge 402 overlaps the light emitting element 20 by no more than 1/6 of the length of the light emitting element.

In some embodiments, the white block 40 is a PET material (polyethylene terephthalate), and the white block 40 is adhered to the first surface.

In the embodiment of the present application, light in the region in front of the light emitting element 20 is absorbed by the black material on the lower surface of the light guide plate; the light in the interval region corresponding to the white block 40 reflects light, and increases the brightness in the interval region corresponding to the light emitting element 20, so that the uniformity of the light in the VA region is effectively improved by reducing the brightness in the front region of the lamp and increasing the brightness in the interval region.

The shape of the white PET is not limited in the embodiment of the present application, and the cross-sectional shape of the white block 40 parallel to the surface of the light bar glue 30 is substantially horn-shaped, and in some embodiments, the edge may be curved, and the edge may also be straight, which is not limited in the present application.

In the embodiment of the application, the light bar is a printed circuit board FPC, and the light emitting elements 20 on the light bar are mutually independent light emitting units located on the same plane and are arranged in a row. The end part of the printed circuit board FPC of the lamp strip is provided with a plurality of connecting ends, and each connecting end is connected with the light emitting unit through a connecting wire. Specifically, the conductive layer of the substrate may include a plurality of connection traces, and each light emitting unit is connected to the connection terminal through the connection trace, respectively. In the embodiment of the present application, the light emitting elements 20 on the light bar are arranged in a three-string-one manner, as shown in fig. 9. However, the present application is not limited thereto, and the light emitting element 20 may be provided in other circuit forms.

In the embodiment of the present application, the adjacent three light emitting elements 20 are one light group, and a plurality of light groups are arranged in an array on the light bar, wherein the plurality of light groups form three light strings arranged in parallel, such as k1\k2\k3 in fig. 9, and the three light emitting elements 20 in each light group are respectively located in different light strings.

It should be noted that, in the embodiment of the present application, the light emitting elements 20 on the light bar may be mixed and arranged on the light bar for LED light sources with different colors, and the arrangement manner may be that the LED light sources are arranged according to a certain sequence or may be arranged randomly, but all LED light sources on the LED strings with each color are distributed on the whole length of the light bar, and through the staggered arrangement of the different color distributions, the colors of the light bar are fully mixed during mixed lighting, so that the overall color development is more uniform.

Illustratively, three color patches A/B/C are used as an illustration, wherein the first color LED is an A color patch, the second color LED is a B color patch, and the third color LED is a C color patch, which are arranged in a manner of A/B/C/A/B/C … A/B/C. Illustratively, two color patches A/B are used as an exemplary illustration, a first color LED is an A color patch, and a second color LED is a B color patch arranged in an A/B/A/B … A/B manner.

It should be noted that, in the embodiment of the present application, the color patches are arranged alternately in turn, and the arrangement order of the colors is not specifically limited, but two adjacent colors are different colors. The color blocks of the same color are preferably arranged at the same interval distance, and the colors are fully mixed after the light enters the light guide plate.

For example, the color of the color patch may be selected to be red or blue; red, green, blue; or red, green, blue, white; the application is not limited to the selection of color block colors and in other embodiments may be selected based on the color gamut requirements of different displays.

In the embodiment of the present application, for example, when three light emitting elements 20 of different colors are provided, one string of light may be provided in series as the same color light emitting element 20. However, the present application is not limited thereto, and different settings may be performed according to different devices or different application scenarios.

In addition, in order to compress the front lamp width of the display device (a schematic view of the front lamp width L1 is shown in fig. 15), it may be compressed from 0.7mm to 0.35mm in the related art.

The back of the light guide plate is also provided with a reflecting sheet, and after the light rays entering the light guide plate are reflected by the reflecting sheet and scattered by the light guide plate, the light rays are emitted from the light emitting surface of the light guide plate, so that the aim of providing a light source for a liquid crystal display to display images is fulfilled. The design of 0.7mm in the prior art enables the reflector to directly enter the VA region, so that the problem of bright band of the VA region can be caused.

The light bar comprises three layers of wiring areas, and each layer of wiring area corresponds to the wiring of each light emitting element 20 in the light string. In the embodiment of the application, the front width of the lamp can be effectively compressed by compressing the wiring area of the FPC and adopting a multilayer wiring mode. It should be noted that, in the embodiment of the present application, the method is not limited to the three-layer routing method, but may be implemented by two or more layers in other embodiments, which is determined according to the total frame size of different devices, and when the two-layer routing method has a routing space, the two-layer routing method may be selected.

Fig. 10 shows a cross-sectional view of a light bar FPC routing area, including a substrate film and routing layers disposed on both sides of the substrate film, where the three-layer routing area of the present application is disposed in a manner including a first routing layer 102, a first adhesive layer, a first substrate film 103, a second adhesive layer, a second routing layer 104, a third adhesive layer, a second substrate film 105, a fourth adhesive layer, and a third routing layer 106, which are sequentially disposed in a stacked manner. Wherein the FPC further includes a first cover film 101 and a second cover film 107 provided on both side surfaces. The covering film and the wiring layer are fixed by an adhesive layer.

As shown in fig. 11, the present application provides a backlight module, which includes a light guide plate 200 and a backlight source as described above located at one side of the light guide plate 200. The backlight module is a side-in backlight module, and provides light to the display screen through the backlight source at one side of the light guide plate 200 so that the display screen displays images.

As shown in fig. 12, the light guide plate 200 includes an array of concave surfaces 201, and the concave surfaces 201 are configured to accommodate the convex lenses 4 of the light emitting elements 20.

In application, the concave surface 201 is provided with an irregular structure 202, the irregular structure 202 includes a plurality of irregular saw-tooth shapes, and the density of the saw-tooth shapes gradually increases from the center of the concave surface 201 to the two ends. The inner concave surface 201 is installed in a gap between the surface of the convex lens 4. The design clearance can be ensured to be 0.05mm.

LGP: light guide plate an optical-grade acrylic/PC board, wherein the surface of the concave surface 201 is provided with an irregular structure 202 for breaking the total reflection of light and converting a linear light source into a uniform surface light source. The LED light is fully mixed after entering the light LGP, so that the Hotspot lamp shadow does not appear after the light of the light source enters the AA area.

In the embodiment of the present application, the irregular structure 202 adopts a zigzag structure, and illustratively, in the embodiment of the present application, the zigzag design parameters are recommended to be R50, P150, H15-R100, P350, H30, wherein R refers to radius, P refers to pitch, H refers to zigzag depth, and the units are um. It should be noted that the design parameters of the saw tooth may be configured according to different devices. In the processing, the film layer of the irregular structure 202 may be attached to the concave surface 201, or the concave surface 201 may be processed irregularly by etching or other processing methods, which is not limited by the forming method of the irregular structure 202 in the present application. By arranging the irregular structure 202, the saw teeth in the middle are sparse, and the two sides are dense, so that the edge position of the inner concave surface 201, namely, the position close to the interval between the light emitting elements 20 can be subjected to light enhancement, the condition of light darkness between lamps can be effectively improved, and the uniformity of light rays of the VA region can be effectively improved. In the embodiment of the application, the backlight module further includes a composite film 300 disposed on the light guide plate 200, the composite film 300 extends from the light guide plate 200 to the position of the light emitting element 20, and the composite film 300 at least covers a portion of the light emitting element 20.

As shown in fig. 13, the composite film 300 includes a composite prism layer 310 and a diffusion layer 320 that are stacked, wherein the composite prism layer 310 includes at least one prism array layer including a first substrate layer 301 and a plurality of prism bodies 302 arrayed on the first substrate layer 301; the diffusion layer 320 includes a second substrate layer 303 and a diffusion particle layer 304 disposed on the second substrate layer, and the diffusion layer 320 is disposed at a side close to the light guide plate 200.

In the embodiment of the present application, two prism array layers are illustrated, and in some embodiments, in order to improve the diffusion effect, a multi-layer manner may be further provided, where each layer in the composite film layer 300 is adhered by an adhesive; the first substrate layer 301 and the second substrate layer may be made of PET film, and the prism body 302 may be a triangular prism, for example, the height of the prism body 302 is 10-70 μm, and the edge angle is 1-160 °. The thickness of the first base material layer 301 is 10 to 300 μm. The particle size of the diffusion particles is 0.1-50 mu m, and the diffusion particles are spherical or ellipsoidal. The diffusion particles are selected from one or a combination of at least two of polymethyl methacrylate, polybutyl methacrylate, polystyrene, siloxane resin, titanium dioxide, calcium carbonate, barium sulfate and silicon dioxide.

In the present application, the diffusion layer 320 is disposed at a side close to the light guide plate 200, the complex prism layer 310 is disposed at a side away from the light guide plate 200, and light exiting from the light guide plate 200 is first atomized by the diffusion film, so that micro-convergence of light by the microstructure or dots of the light guide plate 200 is reduced, the shielding property is improved, and interference fringes occurring between the light guide plate 200 and the LCD panel are advantageously reduced. The prism layer in the light emitting direction is used for intensifying light, so that the optical brightness and the light uniformity of the composite film are greatly enhanced, and better intensifying and diffusing effects can be obtained.

Wherein, the composite film 300 is provided with a plurality of pre-slit seams 330 at the overlap region L2 covering the light emitting element 20, as shown in fig. 14. By providing the pre-slit 330 in the overlap region, on the one hand, heat dissipation can be performed at the position of the light emitting element 20, and on the other hand, when the composite film 300 is expanded by heating, the pre-slit 330 can provide an expansion space, so that the film material is effectively prevented from wrinkling. It should be noted that, in the embodiment of the present application, the pre-slit 330 may have a shape of a straight line, a curved line, or a hole, which is not limited by the present application. Of course, in other embodiments, the pre-slit 330 may be configured to remove portions of the film layer, or may be configured to not be removed. For example, a cut of length 1mm may be removed.

As shown in fig. 15, a schematic positional relationship of a backlight module is shown, in which AA is indicated as a display area, VA is indicated as a visual area, L1 is indicated as a lamp front width distance, L2 is indicated as a length of an overlap area, L3 is indicated as a distance between a reflective sheet and the VA area, and L4 is indicated as a distance between the reflective sheet and the light bar FPC.

The area of the overlap region L2 between the composite film 300 and the light emitting element 20 is not limited to this embodiment, and may cover the light emitting element 20 completely or may cover a part of the light emitting element 20. When the device is applied, the size of the device frame can be adjusted. At the end facing away from the light emitting element 20, it may be flush with the VA region, and may be allowed to extend up to 0.1mm into the VA region.

In the embodiment of the present application, the light guide plate 200 is provided with a silk-screen ink region 500 on the upper surface (a surface near the display panel), and the outer contour of the ink region 500 is flush with the edge of the light guide plate 200, and the inner contour is flush with the contour of the VA region. When set up, it is also possible to allow a maximum of 0.1mm to extend into the VA region. And the edge light leakage of the display device is effectively prevented.

It should be noted that, in the backlight module of the embodiment of the present application, other film layers, such as a polarizer, a front frame of the backlight module, and a back plate, are further included, and the functions of the other film layers and structures on the present application are the same as those of the prior art, so that the detailed description is not given, and the other film layers and structures in the backlight module of the embodiment of the present application are not specifically limited.

In addition, in the embodiment of the present application, by adjusting the reflection sheet 400 to overlap the VA region by a portion L3, for example, by 0.12mm, it is ensured that no bright band or line occurs in the VA region; the back glue design is removed from the reflecting sheet 400, and the distance L4 between the reflecting sheet 400 and the light bar FPC is at least 0.2mm, so that the folding of the reflecting sheet 400 can be effectively prevented.

As shown in fig. 16, the present application further provides a display device, which includes a display panel 1000, a frame 2000, and a backlight module as described above.

In the embodiment of the application, the display panel 1000 includes a display area AA and a visual area VA, the distance between the frame 2000 and the visual area VA of the display panel 1000 is 1.68-2.1 mm, and the distance between the display area AA of the display panel 1000 and the visual area VA is 0.2-0.25 mm.

When the method is used, the distance between VA and AA is preferably set to be 0.2mm, the optical path is enlarged by 0.05mm compared with the conventional mass production design with 0.25mm on the premise that the frame is unchanged, the assembly precision of the shading adhesive and the frame is reduced from 0.13mm to 0.1mm, and the effect of shielding pixels at a large visual angle is ensured.

Fig. 17 shows a key size matching relationship on the socket side of the corresponding display module, where MDL represents a frame size, an outer contour of the frame represents a maximum size from the frame to the display area, PA represents a maximum size from an outer contour of the display panel 1000 to the display area, CP represents a maximum size from the COF to the outer contour of the display panel 1000, CA represents a maximum size from the COF to the display area, and CB represents a size from the COF to the outer contour of the frame.

FIG. 18 is a schematic diagram showing the optical relationship of the backlight source on the socket side of the display module, wherein A is indicated as the position of the cross light; b is denoted as the pitch of the light emitting elements 20; c is denoted as the length of the light emitting element 20; d is represented as the width of the light emitting element 20; e is represented as a light mixing distance of the light emitting element 20; z is expressed as the maximum luminous angle.

Correspondingly, table 2 shows that the minimum frame value corresponding to different LED packages is calculated according to the maximum luminous angle of the LEDs, the frame of the LED module can be compressed from 2.1 to 1.68mm due to the improvement of the luminous angle of the LEDs, the frame is compressed by 0.42mm, and the frame value can be greatly reduced.

TABLE 2

The prior art mass production dimensions, prior art limit dimensions, and the corresponding product dimensions after the light emission angle is increased in the present application are shown in table 3.

TABLE 3 Table 3

Project	PA	CP	CA	CB	MDL
						Mass production size	1.65	1.1	2.75	0.4	2.3
Limit size	1.45	1.0	2.45	0.4	2.05
						Luminous angle elevation	1.45	0.7	2.15	0.35	1.68

As can be seen from tables 2 and 3, in the prior art, the panel frame is compressed to 1.45mm, and when the COF with a thinner substrate is adopted, the module frame needs 2.05 to match, and the COF (Chip on Film) is a die flexible Film packaging technology for fixing a driving IC on a flexible circuit board, and is a technology for bonding a Chip and a flexible substrate circuit by using a flexible additional circuit board as a package Chip carrier. However, the frame of the module can be 1.68mm after the LED luminous angle is lifted, and the requirements of customers can be directly met. At present, the distance between OLED and AA of an OLED product is 1.9mm, and the distance limit between COF and AA can be 2.15mm after an LCD adopts an LED luminous angle lifting scheme, so that the frame of the module can be basically matched with the lower frame of the OLED, and the product competitiveness can be greatly improved.

It is to be understood that the terms "length," "width," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," and the like are merely for convenience in describing and simplifying the description based on the orientation or positional relationship shown in the drawings, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus are not to be construed as limiting the application.

Furthermore, the terms "first," "second," and the like, are used for descriptive purposes only and are not to be construed as indicating or implying a relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defining "a first" or "a second" may explicitly or implicitly include one or more such feature. In the description of the present application, the meaning of "a plurality" is two or more, unless explicitly defined otherwise.

Unless defined otherwise, technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains. The terminology used herein is for the purpose of describing particular implementations only and is not intended to be limiting of the application. Terms such as "disposed" or the like as used herein may refer to either one element being directly attached to another element or one element being attached to another element through an intermediate member. Features described herein in one embodiment may be applied to another embodiment alone or in combination with other features unless the features are not applicable or otherwise indicated in the other embodiment.

The present application has been described in terms of the above embodiments, but it should be understood that the above embodiments are for purposes of illustration and description only and are not intended to limit the application to the embodiments described. Those skilled in the art will appreciate that many variations and modifications are possible in light of the teachings of the application, which variations and modifications are within the scope of the application as claimed.

Claims

1. The backlight source is characterized by comprising a light bar, wherein a plurality of light-emitting elements are arranged on the light bar in an array manner, light bar glue is arranged on the light bar, the light bar glue comprises a first surface and a second surface which are symmetrically arranged, the first surface and the second surface are black, and a plurality of white blocks are arranged on the first surface or the second surface in an array manner;

the array direction of the white blocks is the same as the array direction of the light-emitting elements, a first interval is arranged between two adjacent light-emitting elements, and the white blocks are arranged at the first interval;

the white block is horn-shaped, and comprises a first edge close to the light-emitting element and a second edge deviating from the light-emitting element, and the length of the second edge is greater than that of the first edge.

2. The backlight of claim 1, wherein a length of the first edge is not less than a length of the first pitch; the second side overlaps the light emitting element by a length not exceeding 1/6 of the length of the light emitting element.

3. The backlight of claim 1, wherein the white block is a PET material and the white block is bonded to the first surface.

4. The backlight of claim 1, wherein adjacent three of the light emitting elements are a light string, and a plurality of light strings are arranged in an array on the light bar, wherein the plurality of light strings form three light strings arranged in parallel, and wherein three of the light emitting elements in each light string are located in different light strings.

5. The backlight of claim 4, wherein the light bar comprises three layers of routing regions, each layer of routing region corresponding to a routing of a respective light emitting element in the light string.

6. A backlight module comprising a light guide plate and the backlight of any one of claims 1-5 on one side of the light guide plate.

7. A backlight module according to claim 6, wherein the light guide plate comprises an array of concave surfaces for accommodating the convex lenses of the light emitting elements.

8. A backlight module according to claim 7, wherein the concave surface is provided with an irregular structure, the irregular structure comprises a plurality of irregular saw-tooth shapes, and the density of the saw-tooth shapes gradually increases from the center of the concave surface to the two ends.

9. A backlight module according to claim 7, wherein the concave surface is mounted in a gap between the convex lens surface.

10. A backlight module according to claim 6, further comprising a composite film layer disposed on the light guide plate, the composite film layer extending from the light guide plate to a location of the light emitting element, and the composite film layer covering at least a portion of the light emitting element.

11. The backlight module according to claim 10, wherein the composite film layer comprises a composite prism layer and a diffusion layer which are laminated, wherein,

12. A backlight module according to claim 11, wherein the composite film layer is provided with a plurality of pre-slit in the overlap region covering the light emitting element.

13. A display device comprising a display panel, a frame and a backlight module according to any one of claims 6-12.

14. The display device according to claim 13, wherein a distance between the bezel and the viewable area of the display panel is 1.68-2.1 mm, and a distance between the display area of the display panel and the viewable area is 0.2-0.25 mm.