CN116449605B

CN116449605B - Backlight module and display device

Info

Publication number: CN116449605B
Application number: CN202310429094.3A
Authority: CN
Inventors: 黄皓; 康报虹
Original assignee: HKC Co Ltd
Current assignee: HKC Co Ltd
Priority date: 2023-04-19
Filing date: 2023-04-19
Publication date: 2024-08-06
Anticipated expiration: 2043-04-19
Also published as: CN116449605A

Abstract

The invention relates to the technical field of display, and provides a backlight module and display equipment. The backlight module comprises a light-transmitting substrate and a plurality of light-emitting chips, wherein the light-transmitting substrate is provided with a mounting surface and a diffusion surface, the mounting surface and the diffusion surface are oppositely arranged along the thickness direction of the light-transmitting substrate, and the diffusion surface is used for diffusing light rays; the light-emitting chip is provided with a light-emitting surface, the light-emitting surface is close to the mounting surface, and the light-emitting chip is packaged on the mounting surface, so that light rays emitted by the light-emitting chip enter the light-transmitting substrate through the mounting surface and are diffused to the outside of the light-transmitting substrate through the diffusion surface. The light-emitting chip is arranged on the mounting surface of the light-transmitting substrate through the light-emitting surface, light rays are emitted from the light-emitting surface, directly enter the light-transmitting substrate through the mounting surface and are outwards diffused through the diffusion surface of the light-transmitting substrate, an OD distance is not arranged between the light-emitting chip and the light-transmitting substrate, and the light-transmitting substrate combines the mounting substrate and the diffusion plate into a whole, so that the light-transmitting substrate is favorable for the design of lightening and thinning the backlight module.

Description

Backlight module and display device

Technical Field

The invention relates to the technical field of display, in particular to a backlight module and display equipment.

Background

The backlight module is widely applied to computers, televisions or vehicle-mounted display equipment. The backlight module comprises a substrate, LED chips and a diffusion plate, wherein the thickness of the diffusion plate is about 2mm, the substrate is positioned on one side of the diffusion plate, the substrate and the diffusion plate are arranged at intervals, the LED chips are arranged on the substrate, the LED chips are positioned on one side of the substrate, which is close to the diffusion plate, a OD (optical distance) distance is reserved between the LED chips and the diffusion plate, and the OD distance is about 1 mm-2 mm. The thickness of the existing backlight module is larger, and the design requirement of lightening and thinning is not met.

Disclosure of Invention

The invention aims to provide a backlight module and display equipment, and aims to solve the technical problem that the existing backlight module is large in thickness.

In a first aspect, the present application provides a backlight module, including:

The light-transmitting substrate is provided with a mounting surface and a diffusion surface, the mounting surface and the diffusion surface are oppositely arranged along the thickness direction of the light-transmitting substrate, and the diffusion surface is used for diffusing light rays;

the light-emitting chips are provided with light-emitting surfaces, the light-emitting surfaces are close to the mounting surfaces, the light-emitting chips are packaged on the mounting surfaces, so that light rays emitted by the light-emitting chips enter the light-transmitting substrate through the mounting surfaces and are diffused to the outside of the light-transmitting substrate through the diffusion surfaces.

In one embodiment, the light-transmitting substrate is a frosted glass plate, a bright stone plate, a colorless sapphire plate, a diamond plate, a high-temperature-resistant resin plate or a high-temperature-resistant plastic plate.

In one embodiment, the mounting surface is provided with a driving circuit, the driving circuit forms a plurality of mounting vacancies, the light emitting chip is electrically connected to the driving circuit, and the orthographic projection of the light emitting chip in the thickness direction of the light transmitting substrate overlaps with the orthographic projection of the mounting vacancies in the thickness direction of the light transmitting substrate.

In one embodiment, the mounting void is filled with a transparent insulating layer that is flush with the drive line in the thickness direction of the light-transmitting substrate.

In one embodiment, the backlight module further includes a protective layer, the protective layer is disposed on the mounting surface, and the protective layer is disposed around the light emitting chip.

In one embodiment, the protective layer is a transparent protective layer or a white protective layer.

In one embodiment, the protective layer is a packaging adhesive layer or a heat conducting adhesive layer.

In one embodiment, the intersection points of the side lines corresponding to the light emitting angles of two adjacent light emitting chips fall in the light-transmitting substrate, and the intersection points of the side lines corresponding to the light emitting angles of two light emitting chips separated by one light emitting chip are located outside the light-transmitting substrate.

In one embodiment, assuming that the distance between two adjacent light emitting chips is P and the light emitting angle of the light emitting chips is a, the thickness of the transparent substrate is greater thanAnd is smaller than

In one embodiment, the thickness of the transparent substrate is 1.5 mm-2.5 mm.

In a second aspect, the present application provides a display device, the display device comprising a display panel and a backlight module as described in any one of the preceding claims, the backlight module providing backlight for the display panel.

The backlight module and the display device provided by the invention have the beneficial effects that: the light emitting chip is directly packaged on the mounting surface of the light transmitting substrate, light rays are emitted from the light emitting surface, enter the light transmitting substrate directly through the mounting surface and are diffused to the outside of the light transmitting substrate through the diffusion surface of the light transmitting substrate, the light transmitting substrate combines the mounting substrate and the diffusion plate into a whole, the inside of the light transmitting substrate is used as a light mixing cavity, an OD distance is not required to be arranged between the light emitting chip and the light transmitting substrate, the technical problem that the thickness of an existing backlight module is large is solved, and accordingly the light and thin design of the backlight module is facilitated.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings that are needed in the embodiments or the description of the prior art will be briefly described below, it being obvious that the drawings in the following description are only some embodiments of the present invention, and that other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.

Fig. 1 is a schematic structural diagram of a backlight module according to an embodiment of the application;

Fig. 2 is a schematic structural diagram of a backlight module according to another embodiment of the application;

Fig. 3 is a schematic structural diagram of a backlight module according to another embodiment of the application;

FIG. 4 is a schematic diagram showing the relationship between the spacing of the light emitting chips and the thickness of the transparent substrate in the backlight module;

fig. 5 is a schematic structural diagram of a backlight module according to another embodiment of the application.

Wherein, each reference sign in the figure:

z, thickness direction;

10. a light-transmitting substrate; 11. a mounting surface; 12. a diffusion surface;

20. A light emitting chip; 21. a light emitting surface;

30. A drive line; 31. installing a vacancy; 32. soldering tin;

40. a transparent insulating layer;

50. A protective layer;

60. QD films;

70. an optical film.

Detailed Description

Embodiments of the present invention are described in detail below, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to like or similar elements or elements having like or similar functions throughout. The embodiments described below by referring to the drawings are illustrative and intended to explain the present invention and should not be construed as limiting the invention.

Reference throughout this specification to "one embodiment" or "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the present application. Thus, the appearances of the phrase "in one embodiment" or "in some embodiments" in various places throughout this specification are not necessarily all referring to the same embodiment. Furthermore, the particular features, structures, or characteristics may be combined in any suitable manner in one or more embodiments.

In the description of the present invention, it should be understood that the terms "length," "width," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," and the like indicate orientations or positional relationships based on the orientation or positional relationships shown in the drawings, merely to facilitate describing the present invention and simplify the description, and do not indicate or imply that the devices or elements referred to must have a specific orientation, be configured and operated in a specific orientation, and therefore should not be construed as limiting the present invention.

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 present invention, unless explicitly specified and limited otherwise, the terms "mounted," "connected," "secured," and the like are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally formed; can be mechanically or electrically connected; can be directly connected or indirectly connected through an intermediate medium, and can be communicated with the inside of two elements or the interaction relationship of the two elements. The specific meaning of the above terms in the present invention can be understood by those of ordinary skill in the art according to the specific circumstances.

The light and thin electronic products are now being developed, that is, the display device is also being developed in the light and thin direction, and the backlight module is used as an important component of the display device, and the requirement of the light and thin arrangement is also required to be satisfied.

Referring to fig. 1, a backlight module according to an embodiment of the invention will now be described.

The backlight module comprises a light-transmitting substrate 10 and a plurality of light-emitting chips 20. The light-transmitting substrate 10 has a mounting surface 11 and a diffusion surface 12, the mounting surface 11 and the diffusion surface 12 being disposed opposite to each other in a thickness direction Z of the light-transmitting substrate 10, the diffusion surface 12 being for diffusing light.

The light emitting chip 20 has a light emitting surface 21. The light emitting surface 21 is disposed near the mounting surface 11, and the light emitting chip 20 is packaged on the mounting surface 11, so that light emitted from the light emitting chip 20 enters the light transmitting substrate 10 through the mounting surface 11 and is diffused to the outside of the light transmitting substrate 10 through the diffusion surface 12.

Specifically, the light emitting surface 21 refers to a plane perpendicular to the optical axis of the light emitting chip 20. When the light emitting side of the light emitting chip 20 is a plane, the plane is the light emitting surface 21. For example, the light emitting chip 20 is an LED chip or the like.

When the light emitting chip 20 is an LED chip, since the light emitting surface 21 faces the mounting surface 11, the light is emitted reversely, i.e., the structure of the P/N junction is reversed.

In the present application, the light emitting chip 20 is flip-chip mounted on the mounting surface 11 of the light transmitting substrate 10, and the light emitting direction of the light emitting chip 20 is directed toward the light transmitting substrate 10. Light is emitted from the light emitting surface 21, and directly enters the light transmitting substrate 10 through the mounting surface 11, light is fully mixed in the light transmitting substrate 10, a uniform surface light source is formed at the diffusion surface 12 of the light transmitting substrate 10, and then the light is diffused to the outside of the light transmitting substrate 10 through the diffusion surface 12, the inside of the light transmitting substrate 10 is used as a light mixing cavity, an OD distance is not required to be arranged between the light emitting chip 20 and the light transmitting substrate 10, the light transmitting substrate 10 combines the mounting substrate and the diffusion plate into a whole, the diffusion plate is omitted, and compared with the existing backlight module, the thickness and the OD distance of the diffusion plate are saved, and the light and thin design of the backlight module is facilitated.

Specifically, the thickness of the existing diffusion plate occupies about 40% of the thickness of the optical system, and the backlight module provided by the application is at least thinned by more than 40%. The thickness of the diffusion plate is generally 2mm.

Specifically, the diffusion surface 12 has microstructures distributed in an array, and the microstructures are concave structures or convex structures. When light is emitted to the diffusion surface 12 through the light-transmitting substrate 10, the light is emitted from the concave structure or the convex structure, and the light emitting angle is increased, so that diffusion is realized.

In one embodiment, the light-transmitting substrate 10 is a frosted glass plate, a bright stone plate, a colorless sapphire plate, a diamond plate, a high-temperature-resistant resin plate, or a high-temperature-resistant plastic plate.

When the light-transmitting substrate 10 is a frosted glass plate, the polished surface of the frosted glass plate is a mounting surface 11, and the frosted surface of the frosted glass plate is a diffusion surface 12. Thus, the natural rough surface and the natural smooth surface of the frosted glass plate are used as the diffusion surface 12 and the mounting surface 11, no additional surface processing treatment is needed, and the manufacturing cost is low. Of course, the light-transmitting substrate 10 may be a glass plate with both surfaces being smooth, and the diffusion surface 12 may be formed by roughening one of the surfaces by sand to atomize light.

When the transparent substrate 10 is a bright stone plate, a colorless sapphire plate or a diamond plate, one side of the transparent substrate 10 is cut to form a mounting surface 11, and the other side is subjected to a surface treatment process such as shot blasting to form a diffusion surface 12.

When the transparent substrate 10 is a high temperature resistant resin plate or a high temperature resistant plastic plate, the transparent substrate 10 is extruded or injection molded to form a mounting surface 11 with a smooth surface, and the other surface is embossed to form a diffusion surface 12 with microstructures distributed in an array.

In one embodiment, referring to fig. 2, the mounting surface 11 is provided with a driving circuit 30, the driving circuit 30 forms a plurality of mounting vacancies 31, the light emitting chip 20 is electrically connected to the driving circuit 30, and the front projection of the light emitting chip 20 in the thickness direction Z of the light transmitting substrate 10 overlaps with the front projection of the mounting vacancies 31 in the thickness direction Z of the light transmitting substrate 10. In this way, the driving circuit 30 is used for transmitting electric energy and control instructions to the light emitting chip 20, the light emitting surface 21 of the light emitting chip 20 faces the mounting vacancy 31, and the light emitted by the light emitting chip 20 directly enters the light transmitting substrate 10 through the mounting vacancy 31 without shielding and is diffused outwards through the diffusion surface 12.

The driving wire 30 may be selected from a copper wire, a silver wire, or a gold wire.

Wherein the drive line 30 is made by exposure development. Specifically, first, a dry film is attached to the mounting surface 11, and the dry film covers the preset mounting space 31; secondly, performing exposure and development operations to remove the dry film at the preset driving circuit 30; then, performing a metal plating operation to form a preset driving circuit 30 with a preset thickness on the preset driving circuit 30; and then removing the dry film.

The light emitting chip 20 is electrically connected and fixed to the mounting surface 11 through the driving circuit 30. No optical light mixing sheet is arranged between the light emitting chip 20 and the mounting surface 11, and an OD distance for mixing light is not left, so that the thickness of the backlight module is not increased.

Specifically, the thickness of the drive line 30 is generally 40 μm or less. When the power of the light emitting chip 20 is large, the thickness of the driving wire 30 is 30 μm to 40 μm; when the power of the light emitting chip 20 is small, the thickness of the driving wire 30 is 30 micrometers or less. The drive line 30 does not completely cover the mounting surface 11, and the uncovered position encloses the mounting space 31.

Specifically, one light emitting chip 20 may correspond to one mounting void 31, or may correspond to a plurality of mounting voids 31. For example, one light emitting chip 20 corresponds to one mounting void 31, the number of mounting voids 31 and the number of light emitting chips 20 are one-to-one and equal, and light emitted from each light emitting chip 20 enters the light transmitting substrate 10 through the corresponding mounting void 31. For another example, one light emitting chip 20 corresponds to a plurality of mounting vacancies 31, and light emitted from one light emitting chip 20 is partially directed to some of the mounting vacancies 31 and partially directed to other of the mounting vacancies 31. It is understood that, among the plurality of light emitting chips 20, part of the light emitting chips 20 are in one-to-one correspondence with the mounting vacancies 31, and each of the light emitting chips 20 in part of the light emitting chips 20 is in correspondence with the plurality of mounting vacancies 31; it is also possible that each light emitting chip 20 of all light emitting chips 20 corresponds to one mounting void 31 or a plurality of mounting voids 31.

Specifically, one mounting void 31 may correspond to one light emitting chip 20, or may correspond to a plurality of light emitting chips 20. For example, one mounting void 31 corresponds to one light emitting chip 20, the number of mounting voids 31 and the number of light emitting chips 20 are one-to-one and equal, and light emitted from each light emitting chip 20 enters the light transmitting substrate 10 through the corresponding mounting void 31. For another example, one mounting space 31 corresponds to a plurality of light emitting chips 20, and light emitted from the plurality of light emitting chips 20 is directed to the same mounting space 31. It is understood that among the plurality of mounting vacancies 31, there may be a one-to-one correspondence of partial mounting vacancies 31 with the light emitting chips 20, each mounting vacancy 31 in the partial mounting vacancies 31 corresponding to the plurality of light emitting chips 20; it is also possible that each mounting void 31 of all the mounting voids 31 corresponds to one light emitting chip 20 or a plurality of light emitting chips 20.

In the illustrated embodiment, each light emitting chip 20 is in one-to-one correspondence with each mounting void 31, avoiding interference of light between different light emitting chips 20 before entering the light transmissive substrate 10.

Specifically, the cross-sectional area of the mounting void 31 perpendicular to the thickness direction Z gradually increases in a direction approaching the light emitting chip 20, so that light emitted from the light emitting chip 20 is converged to the light transmitting substrate 10, thereby avoiding light loss, improving the light utilization rate, and improving the light efficiency.

In the illustrated embodiment, the mounting void 31 has a cross-sectional area near an end of the light emitting chip 20 that is approximately equal to the area of the light emitting surface 21 of the light emitting chip 20. For example, the sectional area of the end of the mounting void 31 near the light emitting chip 20 is 80% to 120% of the area of the light emitting surface 21 of the light emitting chip 20.

Specifically, the light emitting chip 20 is electrically connected to the driving circuit 30 through solder 32. The periphery of the light emitting surface 21 is fixedly mounted on the mounting surface 11 by solder 32 and electrically connected with the driving circuit 30.

Specifically, in conjunction with fig. 3, the mounting void 31 is filled with the transparent insulating layer 40, and the transparent insulating layer 40 is flush with the driving wiring 30 in the thickness direction Z of the light-transmitting substrate 10. The transparent insulating layer 40 achieves a flat surface of the mounting surface 11, facilitating the mounting of the light emitting chip 20.

In the embodiment shown in fig. 3, the top of the transparent insulating layer 40 is flush with the top of the driving wiring 30 in the thickness direction Z of the light-transmitting substrate 10, and the bottom of the transparent insulating layer 40 is flush with the bottom of the driving wiring 30. The transparent insulating layer 40 fills the mounting space 31 without a gap between the transparent insulating layer 40 and the driving circuit 30.

It is understood that in other embodiments, as shown in fig. 2, the backlight module is not provided with the transparent insulating layer 40.

In one embodiment, referring to fig. 2 and 3, the backlight module further includes a protective layer 50, the protective layer 50 is disposed on the mounting surface 11, and the protective layer 50 is disposed around the light emitting chip 20. The protective layer 50 can provide a water-oxygen blocking effect, and protect the structures of the driving circuit 30, the light emitting chip 20, and the like.

In one embodiment illustrated, the protective layer 50 fills the space between the light emitting chips 20, and the protective layer 50 is bonded to the light emitting chips 20 without gaps. In the thickness direction Z of the light-transmitting substrate 10, the bottom of the protective layer 50 is flush with the bottom of the light-emitting chip 20, and the thickness of the backlight module is not increased.

It will be appreciated that in other embodiments, in the thickness direction Z of the light-transmitting substrate 10, the protective layer 50 fills the space between the light-emitting chips 20 while covering the side of the light-emitting chips 20 away from the light-emitting surface 21, blocking the water oxygen on the side of the light-emitting chips 20 away from the light-emitting surface 21. Specifically, the thickness of the protective layer 50 protruding from the light emitting chip 20 is 0.5mm or less to reduce the thickness of the backlight module as much as possible.

Specifically, the protective layer 50 is a transparent protective layer or a white protective layer.

Optionally, when the protective layer 50 is a white protective layer, the light emitted by the light emitting chip 20 will be reflected when encountering the white protective layer, and then enter the transparent substrate 10 after being reflected, so as to improve the light utilization rate and the light efficiency.

Alternatively, when the protective layer 50 is a transparent protective layer, the protective layer 50 has no effect on the light emission of the light emitting chip 20. Further, the side surface of the transparent protective layer far away from the transparent substrate 10 is coated with a white coating, so that light emitted by the light emitting chip 20 can be reflected, the light utilization rate is improved, and the light efficiency is improved. It will be appreciated that in other embodiments, the bottom surface of the transparent protective layer is not provided with a white coating.

Specifically, the protective layer 50 is a packaging adhesive layer or a heat conductive adhesive layer.

In some embodiments, the driving circuit 30 is exposed to the protective layer 50 at the edge of the transparent substrate 10, that is, the protective layer 50 does not completely cover the driving circuit 30, and the protective layer 50 does not cover a part of the edge of the transparent substrate 10, so that the driving circuit 30 is exposed at the edge of the transparent substrate 10 and is used for connection with an input port, where the input port may be an FPC (Flexible Printed Circuit, flexible circuit board), an FFC (Flexible Flat Cable ), or a CNT (carbon nanotube) solder, and the specific port structure is not limited.

In one embodiment, referring to fig. 4, the intersection point M of the side lines corresponding to the light emitting angles of two adjacent light emitting chips 20 falls in the light-transmitting substrate 10. If the intersection point M is not located in the transparent substrate 10, the adjacent two light emitting chips 20 do not reach a partial area of the transparent substrate 10, so that the partial area of the transparent substrate 10 is dark, the partial area is bright due to the passing of the light rays of the light emitting chips 20, uneven brightness exists, and obvious dark marks appear. The intersection point N of the side lines corresponding to the light emitting angles of the two light emitting chips 20 separated by one light emitting chip 20 is positioned outside the light transmitting substrate 10, so that light rays emitted by different light emitting chips 20 are prevented from interfering in the light transmitting substrate 10 to form bright spots or bright spots, and lamp shadows are prevented from occurring.

Specifically, assuming that the interval between two adjacent light emitting chips 20 is P and the light emitting angle of the light emitting chip 20 is a, the thickness of the light transmitting substrate 10 is greater thanAnd is smaller thanIn this way, the thickness of the transparent substrate 10 is between the intersection points M and N, so that the light intersection points of two adjacent light emitting chips 20 are accurately ensured to fall in the transparent substrate 10, and the intersection point N between two light emitting chips 20 separated by one light emitting chip 20 is located outside the transparent substrate 10.

Optionally, the light emitting angle a is 100 ° to 150 °. For example, the light emission angle a is 100 °, 110 °, 120 °, 130 °, 140 °, and 150 °.

In the present application, in order to make the backlight module light and thin, the thickness of the transparent substrate 10 is defined, and the light emitting angle of the light emitting chips 20 is defined as A, so as to solve the distance P between two adjacent light emitting chips 20, so that the thickness of the transparent substrate 10 is greater thanAnd is smaller than

For example, the thickness of the light-transmitting substrate 10 is 2mm, the light emission angle a is 120 °, and the pitch P between two adjacent light-emitting chips 20 is 3.46mm to 6.92mm.

From the above analysis, the thickness of the light-transmitting substrate 10 is proportional to the pitch P of the adjacent two light-emitting chips 20. Specifically, the light emitting chip 20 may be a conventional LCD, a Micro LED, or a Mini LED. The Mini LED size is smaller than the traditional LCD size, the Mini LED size is 50-200 mu m, the distance P between two adjacent Mini LEDs is about 3.5mm, the distance P is smaller, the thickness of the corresponding light-transmitting substrate 10 is small, and the Mini LEDs are adopted to replace the traditional LCD, so that the light and thin design of the backlight module is facilitated. The size of Micro LEDs is smaller than 50 μm, the distance P between two adjacent Micro LEDs is smaller than 3.5mm, and the thickness of the corresponding light-transmitting substrate 10 is smaller.

In one embodiment, the thickness of the transparent substrate 10 is 1.5 mm-2.5 mm, so that the thickness of the backlight module is smaller.

Alternatively, the thickness of the light-transmitting substrate 10 is 1.5mm, 1.8mm, 2.0mm, 2.3mm, and 2.5mm.

Because the thin film transistor Liquid crystal display (TFT-LCD, thin Film Transistor-Liquid CRYSTAL DISPLAY) has the advantages of low radiation, small volume, low energy consumption, high image quality and the like, it is widely applied to various electronic information products such as mobile phones, televisions, notebooks, displays and the like, and along with the attack of Organic Light-Emitting Diode (OLED) with high Contrast (CR) and wide color gamut characteristics, the TFT-LCD industry is focused on improving the characteristics of LCD color gamut deficiency, and proposes the concept of quantum dots. Quantum Dots (QDs) are a material with Quantum fluorescence effects. In the display panel of the quantum dot technology, in order to improve the optical efficiency of the QD film 60 and improve the light emitting efficiency of the QD film 60, scattering ions are added into the QD film 60 to fully scatter the light entering the QD film 60, so that the wavelength distribution of the green light and the red light converted by the QD film 60 is very narrow, and the wavelength distribution can be well matched with the high light transmittance band of the CF (colorfilter color filter) of the LCD, thereby reducing the light loss and improving a certain light efficiency. Further, since the wavelength distribution is narrow, RGB monochromatic light of higher color purity (saturation) can be achieved, so the color gamut increases.

Referring to fig. 5, the backlight module provided by the present application further includes a QD film 60, where the QD film 60 is attached to the diffusion surface 12 of the light-transmitting substrate 10 to improve the light efficiency.

Specifically, the QD film 60 has a thickness of 2 μm to 50 μm, and is small, and the QD film 60 is disposed without increasing the thickness of the backlight unit compared to saving the diffusion plate and the OD distance.

It is understood that in other embodiments, the backlight module does not include the QD film 60.

Specifically, the backlight module further includes an optical film 70, and the optical film 70 is attached to a side of the QD film 60 away from the light-transmitting substrate 10. The thickness of the optical film 70 is controlled within 1mm, and the QD film 60 is disposed without increasing the thickness of the backlight module compared with the case where the diffusion plate and the OD distance are saved. The optical film 70 is used to improve the light efficiency.

Optionally, the optical film 70 is a Brightness enhancement film (Brightness ENHANCEMENT FILM) for improving the light-emitting efficiency of the backlight module. For example, the brightness enhancing Film may be one or more of a general prism sheet (Normal PRISM SHEET), a Multi-Functional prism sheet (Multi-Functional PRISM SHEET), a Multi-composite optical Film (Micro-lens Film), and a reflective polarizer (REFLECTIVE POLARIZER).

It is understood that in other embodiments, the backlight module does not include the optical film 70.

The application provides a display device, which comprises a display panel and the backlight module of any one of the above, wherein the backlight module provides backlight for the display panel.

The display panel may be a TN (TWISTED NEMATIC ) display panel, an IPS (In-PLANE SWITCHING ) display panel, a VA (VERTICAL ALIGNMENT, vertically aligned) display panel, an MVA (Multi-Domain VERTICAL ALIGNMENT, multi-Domain vertically aligned) display panel, which is not limited herein.

The foregoing description of the preferred embodiments of the invention is not intended to be limiting, but rather is intended to cover all modifications, equivalents, and alternatives falling within the spirit and principles of the invention.

Claims

1. The utility model provides a backlight unit which characterized in that, backlight unit includes:

The light-transmitting substrate is provided with a mounting surface and a diffusion surface, the mounting surface and the diffusion surface are oppositely arranged along the thickness direction of the light-transmitting substrate, the diffusion surface is used for diffusing light, the mounting surface is provided with a driving circuit, and the driving circuit forms a plurality of mounting vacancies;

The light-emitting chips are provided with light-emitting surfaces, the light-emitting surfaces are close to the mounting surfaces, the light-emitting chips are packaged on the mounting surfaces, so that light emitted by the light-emitting chips enters the light-transmitting substrate through the mounting surfaces and is diffused to the outside of the light-transmitting substrate through the diffusion surfaces, the sectional areas of mounting vacancies in the direction perpendicular to the thickness direction are gradually increased along the direction close to the light-emitting chips, the light-emitting chips are electrically connected and fixed on the mounting surfaces through the driving circuits, and orthographic projections of the light-emitting chips in the thickness direction of the light-transmitting substrate are overlapped with orthographic projections of the mounting vacancies in the thickness direction of the light-transmitting substrate.

2. A backlight module according to claim 1, wherein: the light-transmitting substrate is a frosted glass plate, a bright stone plate, a colorless blue stone plate, a diamond plate, a high-temperature-resistant resin plate or a high-temperature-resistant plastic plate.

3. A backlight module according to claim 1, wherein: the mounting space is filled with a transparent insulating layer which is flush with the drive line in the thickness direction of the light-transmitting substrate.

4. A backlight module according to claim 1, wherein: the backlight module further comprises a protective layer, wherein the protective layer is arranged on the mounting surface, and the protective layer surrounds the light-emitting chip.

5. A backlight module according to claim 4, wherein: the protective layer is a transparent protective layer or a white protective layer;

and/or, the protective layer is an encapsulation adhesive layer or a heat conducting adhesive layer.

6. A backlight module according to claim 1, wherein: the intersection points of the side lines corresponding to the light emitting angles of two adjacent light emitting chips fall in the light transmitting substrate, and the intersection points of the side lines corresponding to the light emitting angles of two light emitting chips which are separated by one light emitting chip are positioned outside the light transmitting substrate.

7. A backlight module according to claim 6, wherein: assuming that the distance between two adjacent light emitting chips is P and the light emitting angle of the light emitting chips is A, the thickness of the light transmitting substrate is larger thanAnd is smaller than。

8. A backlight module according to any one of claims 1 to 7, wherein: the thickness of the light-transmitting substrate is 1.5 mm-2.5 mm.

9. A display device characterized by: the display device comprising a display panel and a backlight module according to any one of claims 1 to 8, the backlight module providing backlight for the display panel.