Patent Description:
A backlight module of an existing display usually uses an edge-type backlight source solution or a direct-type backlight source solution.

A light source of the edge-type backlight source is arranged in a periphery of a light guide plate. Light from the light source enters the light guide plate from the periphery of the light guide plate, and exits from a light emission plane of the light guide plate. The light source requires a particular light mixing distance. Therefore, a non-luminous or dim area is prone to occur around the light guide plate, resulting in uneven light emission. In addition, when the backlight source needs to provide large-area light emission on an entire surface, the light guide plate needs to be thick enough so that a length of a transmission path of internal light is increased. Therefore, the backlight module has a relatively large thickness. As a result, problems such as uneven light emission and a relatively large thickness are prone to occur on the edge-type backlight source.

Lamp beads of the direct-type backlight source need to be packaged separately, to form separate lamp beads that provide white light. Then, the lamp beads are arranged on a backlight board according to a matrix with a relatively large size interval, where the size interval is usually greater than <NUM> millimeters (mm). A prism structure with a special structural design is provided above each lamp bead. In this way, dot-like diverged light from a light source of an LED lamp bead is converted into approximately parallel emergent light of a wider range, and then an even light source is provided at a particular height position (which is usually greater than <NUM> millimeters), thereby providing an even backlight source. Therefore, a light mixing height required by the direct-type backlight source results in a very large overall thickness of the backlight source. As a result, the direct-type backlight source is mainly applied to large-sized liquid crystal display products such as television sets, and can hardly be applied to terminals such as mobile phones that have very high requirements on lightness and thinness.

<CIT> discloses a display device comprising a reflective layer, a first resin layer covering LEDs, a second resin layer formed on the first resin layer, and an optical sheet comprising a diffusion sheet, a prism sheet and a brightness enhanced sheet. At least one of the first resin layer and the second resin layer comprises transparent material particles and phosphor. <CIT> discloses a diode package comprising LEDs covered by a fluorescence layer and further comprising reflecting layers aligned with the LEDs and configured for enhancing the uniformity of the emitted light by transmitting a small portion of the light emitted by the LEDs and reflecting a large portion thereof. <CIT> discloses a lighting device comprising a light-shielding-unit diffusion plate comprising prisms.

Embodiments of this application provide a backlight module that emits light evenly and has a relatively small thickness, and a display screen and a terminal to which the backlight module is applied.

According to a first aspect, the claimed invention provides a backlight module. The backlight module includes a substrate, a plurality of spot light sources, an optical conversion layer, and a light mixing member, wherein: the plurality of spot light sources are fastened onto the substrate in a mutually spaced manner, the optical conversion layer is stacked on the substrate and covers the plurality of spot light sources, the optical conversion layer is configured to convert, into a white surface light source, light emitted by the plurality of spot light sources, wherein the optical conversion layer comprises a packaging layer, a conversion layer including phosphor and/or quantum dots and a protection layer, the packaging layer is made of a transparent material, the packaging layer is in contact with the substrate and encloses the plurality of spot light sources, the protection layer located on a side that is of the conversion layer and that is away from the packaging layer and the conversion layer covers a side that is of the packaging layer and that is away from the substrate, the light mixing member comprises a plurality of diffusion powders exclusively distributed in the packaging layer and the protection layer and the light mixing member is configured to mix the light. The backlight module further comprises an optical membrane assembly located on a side that is of the conversion layer and that is away from the substrate and configured to mix and brighten passing light and comprising a first prism film, a diffusion film, and a second prism film that are stacked, wherein the first prism film is located between the optical conversion layer and the diffusion film and the first prism film and the second prism film cooperate with each other to brighten passing lights.

The optical conversion layer of the backlight module covers all of the plurality of spot light sources, to convert the light from the plurality of spot light sources into the white surface light source. The light mixing member having a light mixing function is embedded into the packaging layer and protections layer to cooperate with the conversion layer to improve light emission evenness of the white surface light source. Therefore, the backlight module evenly emits light, and a light mixing height that is required in an existing direct-type backlight source does not need to be reserved. Therefore, the backlight module has a relatively small thickness, and the backlight module can be applied to a display screen and a terminal that have relatively high requirements on lightness and thinness. The backlight module uses direct light emission and can provide a highly even surface light source. Therefore, the display screen and the terminal to which the backlight module is applied can implement full-screen display, and have a high contrast. In addition, the plurality of spot light sources may be controlled by using a control circuit and a control algorithm, to reduce power consumption, thereby prolonging a battery life.

The plurality of spot light sources are electrically connected to the substrate. The substrate may be a printed circuit board, and the substrate supplies power to the plurality of spot light sources. In an implementation, the plurality of spot light sources are controlled independently by using a circuit on the substrate, so that a working mode in which some spot light sources are lit or a working mode in which all the spot light sources are lit may be selected. This achieves diversified display and can reduce power consumption, thereby prolonging battery life of the backlight module and the display screen and the terminal to which the backlight module is applied. In an implementation, the substrate is a rigid substrate, and the backlight module provides a planar surface light source. In an implementation, the substrate may be a flexible substrate. For example, the substrate may be a flexible printed circuit board. Assembly and mold pressing on the flexible printed circuit board may be implemented by jig design, device modification, and technical parameter adjustment, so that the backlight module provides a curved surface light source and the display screen may be a curved display screen.

Light emitting diode chips are used as the spot light sources. A length of a single light emitting diode chip is within a range of <NUM> millimeter (mm) to <NUM> millimeter; a width of the light emitting diode chip is within a range of <NUM> millimeter to <NUM> millimeter; and a thickness of the light emitting diode chip is within a range of <NUM> millimeter to <NUM> millimeter. The light emitting diode chip is any one of a blue light chip, a green light chip, a red light chip, or a near-ultraviolet light chip. The plurality of spot light sources are approximately arranged as a matrix on the substrate. An onboard layout pitch between the plurality of spot light sources on the substrate is within a range of <NUM> millimeter to <NUM> millimeters. A thickness of the substrate is within a range of <NUM> millimeter to <NUM> millimeter. The plurality of spot light sources are all welded onto the substrate by using a surface mount technology and direct attach or a mass transfer technology, to reduce costs.

The diffusion powders are configured to break up and atomize light, to implement light diffusion and mixing. The diffusion powders are chemical powers with a particle size ranging from <NUM> nanometers (nm) to <NUM> micrometers (µm). A mixing proportion of the diffusion powders in the optical conversion layer is <NUM>-<NUM>%.

The plurality of diffusion powders are distributed in the packaging layer and protection layer. Therefore, the light mixing member does not need to occupy thickness space of the backlight module. This is favorable for lightness and thinness of the backlight module, the display screen, and the terminal. In addition, the light mixing member may be formed while the optical conversion layer is formed. This simplifies a procedure for fabricating the backlight module, reducing fabricating costs of the backlight module.

In an optional embodiment, the optical conversion layer according to this application has a plurality of implementations, and the backlight module may use any one of the implementations. The optical conversion layer may have the following several implementations:.

In an implementation, the optical conversion layer includes a base material, and a phosphor and/or quantum dots distributed in the base material. In other words, the optical conversion layer includes the phosphor; or the optical conversion layer includes the quantum dots; or the optical conversion layer includes the phosphor and the quantum dots. The optical conversion layer is in contact with the substrate and encloses the plurality of spot light sources. The phosphor or the quantum dots are configured to convert, into white light, the light emitted by the plurality of spot light sources. For example, when the plurality of spot light sources emit blue light, the phosphor or the quantum dots can convert the blue light into green light and red light, which are finally mixed to obtain white light.

In a direction perpendicular to the substrate, a thickness of the optical conversion layer is greater than a thickness of the plurality of spot light sources. The thickness of the optical conversion layer is within a range of <NUM> millimeter to <NUM> millimeter.

The phosphor in the base material is in a form of a compound, and may include but is not limited to a red-light phosphor (one or more of oxynitride, fluoride, and nitride), a green-light phosphor (one or both of sialon and silicate), a yellow power (one or both of yttrium aluminium garnet and silicate), and a blue powder (one or both of barium aluminate and aluminate). The base material may be optical silica gel or an ultraviolet-cured glue (UV glue) material. The optical silica gel may include but is not limited to organic silica gel and inorganic silica gel. The organic silica gel includes a compound of one or more of silicone rubber, silicone resin, and silicone oil. The inorganic silica gel includes a compound of one or more of type B silica gel, coarse-porous silica gel, and fine-porous silica gel.

A particle size of the phosphor in the base material ranges from <NUM> micrometers to <NUM> micrometers. A particle size of the quantum dots in the base material ranges from <NUM> nanometers to <NUM> nanometers. A mixing proportion of the phosphor and or the quantum dots in the base material is <NUM>-<NUM>%. A single type of phosphor and/or quantum dots may be mixed, or a plurality of types of phosphor and/or quantum dots may be mixed.

The packaging layer may be made of a transparent material. For example, the packaging layer may be made of optical silica gel or an ultraviolet-cured glue material. A thickness of the packaging layer is greater than a thickness of the plurality of spot light sources. The packaging layer is in contact with the substrate and encloses the plurality of spot light sources. In other words, the packaging layer packages the plurality of spot light sources. The conversion layer includes a phosphor and/or quantum dots. A membrane material of the conversion layer is optical silica gel or an ultraviolet-cured glue material. The phosphor and/or the quantum dots are evenly distributed in the membrane material of the conversion layer. The conversion layer covers a side that is of the packaging layer and that is away from the substrate. The conversion layer is separated from the plurality of spot light sources by the packaging layer. This can effectively prevent the phosphor in a fluorescent layer of the conversion layer from coming into direct contact with the plurality of spot light sources at a high temperature, to prevent the phosphor from being exhausted due to heat, thereby prolonging a service life of the backlight module.

The protection layer may be made of optical silica gel or an ultraviolet-cured glue material, to form a transparent adhesive layer. The protection layer may be formed through mold pressing.

The conversion layer is formed, through coating, spaying, or mold pressing, on a surface that is of the packaging layer and that is away from the substrate. The surface that is of the packaging layer and that is away from the substrate may be a flat plane, so that the conversion layer is formed on the packaging layer with better quality. Alternatively, the conversion layer is an optical conversion membrane. The optical conversion membrane is bonded, by using optical clear adhesive, to the surface that is of the packaging layer and that is away from the substrate; or the optical conversion membrane is fastened, through spaced mounting, onto the surface that is of the packaging layer and that is away from the substrate.

In an implementation, the optical conversion layer includes a first conversion sublayer and a second conversion sublayer. The first conversion sublayer includes a first phosphor. A membrane material of the first conversion sublayer is optical silica gel or an ultraviolet-cured glue material. The first phosphor is evenly distributed in the membrane material of the first conversion sublayer. The first conversion sublayer is in contact with the substrate and encloses the plurality of spot light sources. A thickness of the first conversion sublayer is greater than the thickness of the plurality of spot light sources. The second conversion sublayer includes a second phosphor. A membrane material of the second conversion sublayer is optical silica gel or an ultraviolet-cured glue material. The second phosphor is evenly distributed in the membrane material of the second conversion sublayer. The second conversion sublayer covers a side that is of the first conversion sublayer and that is away from the substrate. The first phosphor and the second phosphor cooperate with each other to convert the light from the plurality of spot light sources into white light. For example, the first phosphor is green phosphor, and the second phosphor is red phosphor; or the first phosphor is red phosphor, and the second phosphor is green phosphor.

The second conversion sublayer is formed, through coating, spaying, or mold pressing, on a surface that is of the first conversion sublayer and that is away from the substrate. The surface that is of the first conversion sublayer and that is away from the substrate may be a flat plane, so that the second conversion layer is formed on the first conversion sublayer with better quality. Alternatively, the second conversion sublayer is an optical conversion membrane. The optical conversion membrane is bonded, by using optical clear adhesive, to the surface that is of the first conversion sublayer and that is away from the substrate; or the optical conversion membrane is fastened, through spaced mounting, onto the surface that is of the first conversion sublayer and that is away from the substrate.

In an implementation, the optical conversion layer includes a plurality of conversion thin films and a packaging element. The plurality of conversion thin films include a phosphor and/or quantum dots. A membrane material of the conversion thin film is optical silica gel or an ultraviolet-cured glue material. The phosphor and/or the quantum dots are evenly distributed in the membrane material of the conversion thin film. The plurality of conversion thin films enclose the plurality of spot light sources in a one-to-one correspondence. The plurality of conversion thin films may be formed on surfaces of the plurality of spot light sources through spraying or by performing mold pressing on the membrane material in a vacuum. The packaging element is made of a transparent material. For example, the packaging element may be made of optical silica gel or an ultraviolet-cured glue material. The packaging element is in contact with the substrate and encloses the plurality of conversion thin films. The packaging element may be formed through mold pressing. A thickness of the packaging element is greater than the thickness of the plurality of spot light sources. A thickness of the conversion thin film is within a range of <NUM> millimeter to <NUM> millimeter.

The optical membrane assembly is configured to mix and brighten passing light. The light emitted by the plurality of spot light sources is mixed for a first time by the light mixing member, and mixed for a second time by the optical membrane assembly, thereby achieving better light emission evenness for the backlight module. An overall thickness of the backlight module according to this application is within a range of <NUM> millimeter to <NUM> millimeters. This is favorable for implementing lightness and thinness of the display screen and the terminal. Power consumption and costs of the backlight module according to this application are equivalent to those of an existing edge-type backlight source.

In an implementation, the optical membrane assembly is bonded to the optical conversion layer by using a bonding layer. The bonding layer fastens the optical membrane assembly and the optical conversion layer together, and a connection relationship is reliable. In addition, compared to air, the bonding layer can effectively improve light extraction efficiency and reduce optical losses. The bonding layer includes diffusion particles. A proportion of the diffusion particles is within a range of <NUM>-<NUM>%, to meet both a transparency requirement and a light mixing requirement. A diameter of the diffusion particles added into the bonding layer is within a range of <NUM> nanometers to <NUM> micrometers. A material of the diffusion particles includes but is not limited to polymethyl methacrylate, silicon dioxide, metal ions, and the like. A difference between a refractive index of scattering particles and a refractive index of adhesive of the bonding layer is within a range of <NUM>-<NUM>. After the diffusion particles are added, a light transmittance of the bonding layer is greater than <NUM>%.

In an implementation, the backlight module further includes a backplane, a plastic frame, and square-shaped adhesive. The plastic frame is connected around the backplane, to jointly encircle an accommodation space. The substrate, the optical conversion layer, and the optical membrane assembly are all accommodated in the accommodation space. The square-shaped adhesive bonds the optical membrane assembly and the plastic frame. In this case, the optical membrane assembly is mounted on the optical conversion layer in a spaced manner, and there is an air gap between the optical membrane assembly and the optical conversion layer.

The optical membrane assembly further includes a plurality of light mixing thin films. The light mixing thin films are configured to transmit some light and reflect the other light. The plurality of light mixing thin films are located on a surface of the optical membrane assembly facing the optical conversion layer. The plurality of light mixing thin films are aligned with the plurality of spot light sources in a one-to-one correspondence. In other words, the plurality of light mixing thin films are located right above the plurality of spot light sources in a one-to-one correspondence. The plurality of light mixing thin films can further reduce the luminance in the central area of the plurality of spot light sources, to achieve the light mixing effect, thereby achieving better light emission evenness for the backlight module.

The diffusion film is configured to provide an even surface light source for the backlight module. A material having a high light transmittance, for example, PET/PC/PMMA, needs to be selected as a base material of the diffusion film. The diffusion film is mainly made by adding chemical grains as scattering particles into the base material of the diffusion film. However, in an existing diffusion board, micro-particles are distributed between resin layers. As a result, when passing through the diffusion film, light constantly passes through two media having different refractive indexes. In this process, the light is refracted, reflected, and scattered, resulting in an optical diffusion effect. The diffusion film includes an antistatic coating layer, a PET base material, and a diffusion layer that are stacked in sequence in a light emission direction. The diffusion film may be a scattered particle-type diffusion film, a bulk diffusion film, or the like.

The first prism film and the second prism film each are a transparent plastic thin film with a thickness between <NUM> and <NUM> micrometers. A layer of prism structure is overlaid evenly and neatly on an upper surface of the thin film. The first prism film and the second prism film are configured to improve angular distribution of light, so that diverged light is converged to an axial angle, that is, a front view angle. This improves axial luminance without increasing an overall emergent luminous flux, thereby implementing brightening. A membrane material of the first prism film and the second prism film each may be a single-layer prism film or a double-layer bonding prism film (an angle between the two layers may be changed as required). A prism shape may be a regular strip prism, a pyramid, a frustum, a cone, or the like. Prism patterns may use different parameters, for example, different angles (for example, vertex angles of <NUM>° to <NUM>°); a cycle is changed as required; or the like.

The first prism film and the diffusion film are bonded by using a transparent bonding layer, and the diffusion film and the second prism film are bonded by using a transparent bonding layer. The transparent bonding layer may be made of optical silica gel or an ultraviolet-cured glue material. Diffusion particles may be added into the transparent bonding layer to enhance the light mixing effect. Certainly, in another implementation, alternatively, the first prism film and the diffusion film may be fastened by using adhesive in a periphery, and the diffusion film and the second prism film may be fastened by using adhesive in a periphery, to implement spaced mounting. In this case, there is an air gap between the first prism film and the diffusion film, and there is an air gap between the diffusion film and the second prism film. Adhesive of the transparent bonding layer may be fluid, and formed through slit coating (Slit Coating) or spraying. Alternatively, adhesive of the transparent bonding layer may be a plate viscoelastic body.

In another implementation, not according to the claimed invention, a combination manner of the optical membrane assembly may be: a diffusion film + a prism film; or a diffusion film + a prism film + a diffusion film + a prism film. A topmost layer that is of the optical membrane assembly and that is away from the optical conversion layer is a prism film.

In a specific embodiment, the foregoing various implementations of the light mixing member, the foregoing various implementations of the optical conversion layer, and the foregoing various implementations of the optical membrane assembly may be combined randomly.

According to a second aspect, an embodiment of this application further provides a display screen, including a liquid crystal display panel and any one of the foregoing backlight modules. The backlight module is configured to provide a backlight source for the liquid crystal display panel. The backlight module emits light evenly and has a relatively small thickness. Therefore, the display screen can implement full-screen display, and has a high contrast and a small thickness.

According to a third aspect, an embodiment of this application further provides a terminal. The terminal includes the foregoing display screen. The terminal can implement full-screen display, has a high contrast, and is light and thin.

To describe the technical solutions in the embodiments of this application or in the background art more clearly, the following briefly describes the accompanying drawings required for describing the embodiments of this application or the background art.

The sixth implementation of a backlight module shown in <FIG> is an embodiment of the claimed invention. The other implementations are embodiments of the claimed invention only if combined with the optical conversion layer comprising diffusion powders exclusively in the packaging layer and the protection layer as described in said sixth implementation of a backlight module.

The following describes embodiments of this application with reference to the accompanying drawings in the embodiments of this application.

With reference to <FIG>, an embodiment of this application provides a terminal <NUM>. The terminal <NUM> in this embodiment of this application may be any device having communication and storage functions, for example, an intelligent device having a network function, such as a tablet computer, a mobile phone, an e-reader, a remote control, a personal computer (Personal Computer, PC), a notebook computer, a vehicle-mounted device, a web television, a wearable device, or a television. The terminal <NUM> includes a display screen <NUM>. The display screen <NUM> may be a touch display screen. The display screen <NUM> includes a liquid crystal display panel <NUM> and a backlight module <NUM>. The backlight module <NUM> is configured to provide a backlight source (Back Light) for the liquid crystal display panel <NUM>.

The backlight module <NUM> and the liquid crystal display panel <NUM> are stacked. The backlight module <NUM> and the liquid crystal display panel <NUM> are mounted in a spaced manner. A basic rule in which the liquid crystal display panel <NUM> performs display is as follows: A liquid crystal material is padded between two parallel plates, and there are many vertical and horizontal tiny wires between two pieces of glass. Rod-shaped crystal molecules are controlled, by energizing or not energizing the tiny wires, to change directions to generate a picture through refraction of light. An arrangement status of molecules inside the liquid crystal material is changed by using voltage, to block light or transmit light, thereby displaying a well-arranged image with different shades. In addition, a colored image can be displayed by adding a tricolor filter layer between the two flat plates. The display screen <NUM> further includes a coverplate <NUM>. The coverplate <NUM> is stacked on a side that is of the liquid crystal display panel <NUM> and that is away from the backlight module <NUM>. The coverplate <NUM> is configured to protect the liquid crystal display panel <NUM>. The coverplate <NUM> and the liquid crystal display panel <NUM> may be bonded by using optical clear adhesive (Optically Clear Adhesive, OCA).

With reference to <FIG>, an embodiment of this application further provides a backlight module <NUM>. The backlight module <NUM> includes a substrate <NUM>, a plurality of spot light sources <NUM>, an optical conversion layer <NUM>, and a light mixing member <NUM>. The plurality of spot light sources <NUM> are fastened onto the substrate <NUM> in a mutually spaced manner. The optical conversion layer <NUM> is stacked on the substrate <NUM> and covers the plurality of spot light sources <NUM>. The optical conversion layer <NUM> is configured to convert light from the plurality of spot light sources <NUM> into a white surface light source. A light emission plane of the white surface light source is approximately parallel to the substrate <NUM>, and the backlight module <NUM> emits light in a direct manner. The light mixing member <NUM> is located on a surface of the optical conversion layer <NUM> or embedded into the optical conversion layer <NUM>. An implementation in which the light mixing member <NUM> is located on the surface of the optical conversion layer <NUM> is shown in <FIG>, and an implementation in which the light mixing member <NUM> is embedded into the optical conversion layer <NUM> is shown in <FIG> and <FIG>. The light mixing member <NUM> is configured to mix the light.

In this embodiment, the optical conversion layer <NUM> of the backlight module <NUM> covers all of the plurality of spot light sources <NUM>, to convert the light of the plurality of spot light sources <NUM> into the white surface light source. The light mixing member <NUM> having a light mixing function is disposed on the surface of the optical conversion layer <NUM> or embedded into the optical conversion layer <NUM>, to cooperate with the optical conversion layer <NUM> to improve light emission evenness of the white surface light source. Therefore, the backlight module <NUM> evenly emits light, and a light mixing height that is required in an existing direct-type backlight source does not need to be reserved. Therefore, the backlight module <NUM> has a relatively small thickness, and the backlight module <NUM> can be applied to the display screen <NUM> and the terminal <NUM> that have relatively high requirements on lightness and thinness. The backlight module <NUM> uses direct light emission and can provide a highly even surface light source. Therefore, the display screen <NUM> and the terminal <NUM> to which the backlight module <NUM> is applied can implement full-screen display, and have a high contrast (HDR). In addition, the plurality of spot light sources <NUM> may be controlled by using a control circuit and a control algorithm, to reduce power consumption, thereby prolonging a battery life.

Optionally, with reference to <FIG>, the plurality of spot light sources <NUM> are electrically connected to the substrate <NUM>. The substrate <NUM> may be a printed circuit board, and the substrate <NUM> supplies power to the plurality of spot light sources <NUM>. In an implementation, the plurality of spot light sources <NUM> are controlled independently by using a circuit on the substrate <NUM>, so that a working mode in which some spot light sources are lit or a working mode in which all the spot light sources are lit may be selected. This achieves diversified display and can reduce power consumption, thereby prolonging battery life of the backlight module <NUM> and the display screen <NUM> and the terminal <NUM> to which the backlight module <NUM> is applied. In an implementation, as shown in <FIG>, the substrate <NUM> is a rigid substrate, and the backlight module <NUM> provides a planar surface light source. In an implementation, as shown in <FIG>, the substrate <NUM> may be a flexible substrate. For example, the substrate <NUM> may be a flexible printed circuit board (Flexible Printed Circuit, FPC). Assembly and mold pressing on the flexible printed circuit board may be implemented by jig design, device modification, and technical parameter adjustment, so that the backlight module <NUM> provides a curved surface light source and the display screen <NUM> may be a curved display screen <NUM>.

Optionally, with reference to <FIG>, a light emitting diode (Light Emitting Diode, LED) chip is used as the spot light source <NUM>. A length of a single light emitting diode chip is within a range of <NUM> millimeter (mm) to <NUM> millimeter; a width of the light emitting diode chip is within a range of <NUM> millimeter to <NUM> millimeter; and a thickness of the light emitting diode chip is within a range of <NUM> millimeter to <NUM> millimeter. The light emitting diode chip is any one of a blue light chip, a green light chip, a red light chip, or a near-ultraviolet light chip. The plurality of spot light sources <NUM> are approximately arranged as a matrix on the substrate <NUM>. An onboard layout pitch (pitch) between the plurality of spot light sources <NUM> on the substrate <NUM> is within a range of <NUM> millimeter to <NUM> millimeters. A thickness of the substrate <NUM> is within a range of <NUM> millimeter to <NUM> millimeter. The plurality of spot light sources <NUM> are all welded onto the substrate <NUM> by using a surface mount technology (Surface Mount Technology, SMT) and direct attach (Direct Attach, DA) or a mass transfer (Mass transfer) technology, to reduce costs.

In an embodiment, the substrate <NUM> includes a white base material <NUM>, a white ink layer <NUM>, and a plurality of pads <NUM>. The white ink layer <NUM> covers the white base material <NUM>. The plurality of pads <NUM> are fastened onto the white base material <NUM>. The white ink layer <NUM> has a plurality of hollowed areas, which are used to expose the plurality of pads <NUM>. Pins <NUM> of the plurality of spot light sources <NUM> are correspondingly welded onto the plurality of pads <NUM>.

In an optional embodiment, with reference to <FIG>, the light mixing member <NUM> according to this application has a plurality of implementations. The light mixing member <NUM> in the backlight module <NUM> may use only one of the implementations or a combination of a plurality of the implementations, to improve a light mixing effect. The light mixing member <NUM> may have the following several implementations:
<FIG> show a first implementation of the light mixing member <NUM>.

The light mixing member <NUM> includes a plurality of diffusion powders <NUM>. The plurality of diffusion powders <NUM> are distributed in the optical conversion layer <NUM>. The diffusion powders <NUM> are used to break up and atomize light, to implement light diffusion and mixing. The diffusion powders <NUM> are chemical powers with a particle size ranging from <NUM> nanometers (nm) to <NUM> micrometers (µm). A mixing proportion of the diffusion powders <NUM> in the optical conversion layer <NUM> is <NUM>-<NUM>%.

In the first implementation, the plurality of diffusion powders <NUM> are distributed in the optical conversion layer <NUM>. Therefore, the light mixing member <NUM> does not need to occupy thickness space of the backlight module <NUM>. This is favorable for lightness and thinness of the backlight module <NUM>, the display screen <NUM>, and the terminal <NUM>. In addition, the light mixing member <NUM> may be formed while the optical conversion layer <NUM> is formed. This simplifies a procedure for fabricating the backlight module <NUM>, reducing fabrication costs of the backlight module <NUM>.

<FIG> and <FIG> respectively show a second implementation and a third implementation of the light mixing member <NUM>.

The light mixing member <NUM> includes a plurality of membranes <NUM>. The plurality of membranes <NUM> are configured to transmit some light and reflect the other light. The plurality of membranes <NUM> are thin film structures having transmission and reflection functions. The plurality of membranes <NUM> are embedded into the optical conversion layer <NUM> or located on a surface that is of the optical conversion layer <NUM> and that is away from the substrate <NUM>. The plurality of membranes <NUM> are aligned with the plurality of spot light sources <NUM> in a one-to-one correspondence. In other words, the plurality of membranes <NUM> are located right above the plurality of spot light sources <NUM> in a one-to-one correspondence.

The second implementation of the light mixing member <NUM> is as follows: The plurality of membranes <NUM> may be in contact with both the plurality of spot light sources <NUM> and the optical conversion layer <NUM>. For example, as shown in <FIG>, the plurality of membranes <NUM> are laminated onto upper surfaces of the plurality of spot light sources <NUM> in a one-to-one correspondence. In this case, the optical conversion layer <NUM> encloses both the plurality of spot light sources <NUM> and the plurality of membranes <NUM>. The third implementation of the light mixing member <NUM> is as follows: The plurality of membranes <NUM> are completely enclosed by the optical conversion layer <NUM>, or located on a surface that is of the optical conversion layer <NUM> and that is away from the substrate <NUM> (as shown in <FIG>). In this case, the plurality of membranes <NUM> are not in contact with the spot light source <NUM>, and the plurality of membranes <NUM> and the plurality of spot light sources <NUM> are disposed in a spaced manner. It can be understood that when the optical conversion layer <NUM> includes a plurality of film layers that are stacked, and when the plurality of membranes <NUM> are located between two film layers of the plurality of film layers, the plurality of membranes <NUM> are completely enclosed by the optical conversion layer <NUM>.

In the second implementation and the third implementation of the light mixing member <NUM>, the plurality of membranes <NUM> are aligned with the plurality of spot light sources <NUM>, and the membranes <NUM> have transmission and reflection functions. Therefore, the plurality of membranes <NUM> can reduce luminance in a central area of the plurality of spot light sources <NUM>, thereby achieving a light mixing effect.

Optionally, a size of the membrane <NUM> is set based on a distance between the membrane <NUM> and the spot light source <NUM> and a light emission angle of the spot light source <NUM> by considering both a light mixing effect and overall light emission luminance of the backlight module <NUM>. When the membrane <NUM> is close to the spot light source <NUM>, the size of the membrane <NUM> is relatively small; or when the membrane <NUM> is far away from the spot light source <NUM>, the size of the membrane is relatively large. For example, when the membrane <NUM> is in contact with the upper surface of the spot light source <NUM> (in other words, away from a surface of the substrate <NUM>), the size of the membrane <NUM> is smaller than a size of the upper surface of the spot light source <NUM>; or when the membrane <NUM> is located on an upper surface that is of the optical conversion layer <NUM> and that is away from the spot light source <NUM>, the size of the membrane <NUM> is greater than a size of the upper surface (that is, a surface away from the substrate <NUM>) of the spot light source <NUM>.

A shape of the membrane <NUM> may be determined according to an optical design. For example, the shape may be a circle or a square. A material of the membrane <NUM> may be an amorphous membrane of titanic oxide or silicon oxide; may be distributed as particles in a solvent; may be a thin layer coated with metal such as aluminum, copper, or silver; may be a photonic crystal-related material such as a distributed Bragg reflector (distributed Bragg reflection, DBR) or an enhanced specular reflector (Enhanced Specular Refector, ESR); may be optical glue or a white ink layer with a high refractive index; or the like. A thickness of the membrane <NUM> is within a range of <NUM> micrometer to <NUM> micrometers. Certainly, the membrane <NUM> may alternatively be set to another thickness based on an optical design requirement. A transmittance and a reflectivity of the membrane <NUM> are designed based on a light mixing requirement. A size of the membrane <NUM> is adjusted based on the light mixing requirement and the transmittance and the reflectivity.

Optionally, in a direction perpendicular to the substrate <NUM>, a plurality of membranes <NUM> may be arranged above a single spot light source <NUM> in a spaced manner, to implement a plurality of times of reflection and a plurality of times of transmission. This further reduces luminance in a central area right above the spot light source <NUM>, thereby achieving even light mixing. In this case, the backlight module <NUM> can still ensure even light emission while using the spot light source <NUM> having higher power and higher luminance.

<FIG> and <FIG> to <FIG> show a fourth implementation of the light mixing member <NUM>.

The light mixing member <NUM> includes a plurality of micro structural blocks <NUM>, and the plurality of micro structural blocks <NUM> are configured to perform optical diffusion on light. The plurality of micro structural blocks <NUM> are embedded into the optical conversion layer <NUM> or located on a surface that is of the optical conversion layer <NUM> and that is away from the substrate <NUM>. The plurality of micro structural blocks <NUM> are configured to perform optical diffusion on passing light, to achieve a light mixing effect. The plurality of micro structural blocks <NUM> may be a plurality of mutually spaced lens blocks, or may be an integrated lens in a special shape.

Optionally, a related surface shape of the micro structural block <NUM> may be implemented through imprinting, etching, diamond cutting, or the like. The surface shape may be a sphere, a hemisphere, or an ellipsoid shown in <FIG>, a cylinder or a cuboid shown in <FIG>, or a prism shape or a prism column shape shown in <FIG>.

<FIG> shows a fifth implementation of the light mixing member <NUM>.

The light mixing member <NUM> includes a reflective film <NUM>. The reflective film <NUM> is provided with a plurality of hollowed areas. The reflective film <NUM> is located on a surface of the optical conversion layer <NUM> facing the substrate <NUM>. The reflective film <NUM> is in contact with the substrate <NUM>, and the plurality of spot light sources <NUM> are located in the plurality of hollowed areas in a one-to-one correspondence. The reflective film <NUM> may be made of a membrane material having a high reflectivity, for example, DBR or ESR. A reflectivity of the reflective film <NUM> is greater than or equal to <NUM>%. A thickness of the reflective film <NUM> is from <NUM> millimeter to <NUM> millimeter. The reflective film <NUM> improves light utilization while implementing light mixing, thereby ensuring optical efficiency of the plurality of spot light sources <NUM> and reducing power consumption of the backlight module <NUM>.

With reference to <FIG> and <FIG>, in an optional embodiment, the optical conversion layer <NUM> according to this application has a plurality of implementations, and the backlight module <NUM> may use any one of the implementations. The optical conversion layer <NUM> may have the following several implementations:
<FIG> show a first implementation of the optical conversion layer <NUM>.

The optical conversion layer <NUM> includes a base material <NUM>, and a phosphor and/or quantum dots <NUM> distributed in the base material <NUM>. In other words, the optical conversion layer <NUM> includes the phosphor; or the optical conversion layer <NUM> includes the quantum dots; or the optical conversion layer <NUM> includes the phosphor and the quantum dots. In this embodiment of this application, "X and/or Y" includes three solutions in total: an "X" solution, a "Y" solution, and an "X and Y" solution. The optical conversion layer <NUM> is in contact with the substrate <NUM> and encloses the plurality of spot light sources <NUM>. The phosphor or the quantum dots <NUM> are configured to convert, into white light, the light emitted by the plurality of spot light sources <NUM>. For example, when the plurality of spot light sources <NUM> emit blue light, the phosphor or the quantum dots <NUM> can convert the blue light into green light and red light, which are finally mixed to obtain white light.

Optionally, in the direction perpendicular to the substrate <NUM>, a thickness of the optical conversion layer <NUM> is greater than a thickness of the plurality of spot light sources <NUM>. The thickness of the optical conversion layer <NUM> is within a range of <NUM> millimeter to <NUM> millimeter.

The phosphor <NUM> in the base material <NUM> is in a form of a compound, and may include but is not limited to a red-light phosphor (one or more of oxynitride, fluoride, and nitride), a green-light phosphor (one or both of sialon and silicate), a yellow powder (one or both of yttrium aluminium garnet and silicate), and a blue powder (one or both of barium aluminate and aluminate). The base material <NUM> may be optical silica gel or an ultraviolet-cured glue (UV glue) material. The optical silica gel may include but is not limited to organic silica gel and inorganic silica gel. The organic silica gel includes a compound of one or more of silicone rubber, silicone resin, and silicone oil. The inorganic silica gel includes a compound of one or more of type B silica gel, coarse-porous silica gel, and fine-porous silica gel.

A particle size of the phosphor in the base material <NUM> ranges from <NUM> micrometers to <NUM> micrometers. A particle size of the quantum dots in the base material <NUM> ranges from <NUM> nanometers to <NUM> nanometers. A mixing proportion of the phosphor and or the quantum dots in the base material <NUM> is <NUM>-<NUM>%. A single type of phosphor and/or quantum dots may be mixed, or a plurality of types of phosphor and/or quantum dots may be mixed. The diffusion powders <NUM> may be distributed in the optical conversion layer <NUM>, to improve the light mixing effect.

<FIG> shows a second implementation of the optical conversion layer <NUM>, which is an embodiment according to the claimed invention.

The optical conversion layer <NUM> includes a packaging layer <NUM> and a conversion layer <NUM>. The packaging layer <NUM> is made of a transparent material. For example, the packaging layer <NUM> may be made of optical silica gel or an ultraviolet-cured glue material. A thickness of the packaging layer <NUM> is greater than a thickness of the plurality of spot light sources <NUM>. The packaging layer <NUM> is in contact with the substrate <NUM> and encloses the plurality of spot light sources <NUM>. In other words, the packaging layer <NUM> packages the plurality of spot light sources <NUM>. The conversion layer <NUM> includes a phosphor and/or quantum dots <NUM>. A membrane material of the conversion layer <NUM> is optical silica gel or an ultraviolet-cured glue material. The phosphor and/or the quantum dots <NUM> are evenly distributed in the membrane material of the conversion layer <NUM>. The conversion layer <NUM> covers a side that is of the packaging layer <NUM> and that is away from the substrate <NUM>. The conversion layer <NUM> is separated from the plurality of spot light sources <NUM> by the packaging layer <NUM>. This can effectively prevent the phosphor <NUM> in a fluorescent layer of the conversion layer <NUM> from coming into direct contact with the plurality of spot light sources <NUM> at a high temperature, to prevent the phosphor <NUM> from being exhausted due to heat, thereby prolonging a service life of the backlight module <NUM>.

The optical conversion layer <NUM> further includes a protection layer <NUM>. The protection layer <NUM> is located on a side that is of the conversion layer <NUM> and that is away from the packaging layer <NUM>. The protection layer <NUM> may be made of optical silica gel or an ultraviolet-cured glue material, to form a transparent adhesive layer. The protection layer <NUM> may be formed through mold pressing.

Optionally, the conversion layer <NUM> is formed, through coating, spaying, or mold pressing, on a surface that is of the packaging layer <NUM> and that is away from the substrate <NUM>. The surface that is of the packaging layer <NUM> and that is away from the substrate <NUM> may be a flat plane, so that the conversion layer <NUM> is formed on the packaging layer <NUM> with better quality. Alternatively, the conversion layer <NUM> is an optical conversion membrane. The optical conversion membrane is bonded, by using optical clear adhesive, to the surface that is of the packaging layer <NUM> and that is away from the substrate <NUM>; or the optical conversion membrane is fastened, through spaced mounting, onto the surface that is of the packaging layer <NUM> and that is away from the substrate <NUM>. In the claimed invention, the diffusion powders <NUM> are exclusively distributed in the packaging layer <NUM> and the protection layer <NUM>, to achieve the light mixing effect.

<FIG> shows a third implementation of the optical conversion layer <NUM>.

The optical conversion layer <NUM> includes a first conversion sublayer <NUM> and a second conversion sublayer <NUM>. The first conversion sublayer <NUM> includes a first phosphor <NUM>. A membrane material of the first conversion sublayer <NUM> is optical silica gel or an ultraviolet-cured glue material. The first phosphor <NUM> is evenly distributed in the membrane material of the first conversion sublayer <NUM>. The first conversion sublayer <NUM> is in contact with the substrate <NUM> and encloses the plurality of spot light sources <NUM>. A thickness of the first conversion sublayer <NUM> is greater than the thickness of the plurality of spot light sources <NUM>. The second conversion sublayer <NUM> includes a second phosphor <NUM>. A membrane material of the second conversion sublayer <NUM> is optical silica gel or an ultraviolet-cured glue material. The second phosphor <NUM> is evenly distributed in the membrane material of the second conversion sublayer <NUM>. The second conversion sublayer <NUM> covers a side that is of the first conversion sublayer <NUM> and that is away from the substrate <NUM>. The first phosphor <NUM> and the second phosphor <NUM> cooperate with each other to convert the light from the plurality of spot light sources <NUM> into white light. For example, the first phosphor <NUM> is green phosphor, and the second phosphor <NUM> is red phosphor; or the first phosphor <NUM> is red phosphor, and the second phosphor <NUM> is green phosphor.

Optionally, the second conversion sublayer <NUM> is formed, through coating, spaying, or mold pressing, on a surface that is of the first conversion sublayer <NUM> and that is away from the substrate <NUM>. The surface that is of the first conversion sublayer <NUM> and that is away from the substrate <NUM> may be a flat plane, so that the second conversion layer <NUM> is formed on the first conversion sublayer <NUM> with better quality. Alternatively, the second conversion sublayer <NUM> is an optical conversion membrane. The optical conversion membrane is bonded, by using optical clear adhesive, to the surface that is of the first conversion sublayer <NUM> and that is away from the substrate <NUM>; or the optical conversion membrane is fastened, through spaced mounting, onto the surface that is of the first conversion sublayer <NUM> and that is away from the substrate <NUM>. The diffusion powders <NUM> may be distributed in the first conversion sublayer <NUM> and/or the second conversion sublayer <NUM>.

<FIG> shows a fourth implementation of the optical conversion layer <NUM>.

The optical conversion layer <NUM> includes a plurality of conversion thin films <NUM> and a packaging element <NUM>. The plurality of conversion thin films <NUM> include a phosphor and/or quantum dots <NUM>. A membrane material of the conversion thin film <NUM> is optical silica gel or an ultraviolet-cured glue material. The phosphor and/or the quantum dots <NUM> are evenly distributed in the membrane material of the conversion thin film <NUM>. The plurality of conversion thin films <NUM> enclose the plurality of spot light sources <NUM> in a one-to-one correspondence. The plurality of conversion thin films <NUM> may be formed on surfaces of the plurality of spot light sources <NUM> through spraying or by performing mold pressing on the membrane material in a vacuum. The packaging element <NUM> is made of a transparent material. For example, the packaging element <NUM> may be made of optical silica gel or an ultraviolet-cured glue material. The packaging element <NUM> is in contact with the substrate <NUM> and encloses the plurality of conversion thin films <NUM>. The packaging element <NUM> may be formed through mold pressing. A thickness of the packaging element <NUM> is greater than a thickness of the plurality of spot light sources <NUM>. A thickness of the conversion thin film <NUM> is within a range of <NUM> millimeter to <NUM> millimeter. The diffusion powders <NUM> may be distributed in the conversion thin films <NUM> and/or the packaging element <NUM>, to improve the light mixing effect.

Optionally, a protection film layer may be further disposed on the upper surface that is of the optical conversion layer <NUM> and that is away from the substrate. The protection film layer may be made of optical silica gel or an ultraviolet-cured glue material, to form a transparent adhesive layer. The diffusion powders <NUM> may be distributed in the protection film layer, to improve the light mixing effect. The protection film layer may be shaped through mold pressing.

With reference to <FIG> and <FIG>, the backlight module <NUM> further includes an optical membrane assembly <NUM>. The optical membrane assembly <NUM> is located on a side that is of the optical conversion layer <NUM> and that is away from the substrate <NUM>. The optical membrane assembly <NUM> is configured to mix and brighten passing light. The light emitted by the plurality of spot light sources <NUM> is mixed for a first time by the light mixing member <NUM>, and mixed for a second time by the optical membrane assembly <NUM>, thereby achieving better light emission evenness for the backlight module <NUM>. An overall thickness of the backlight module <NUM> according to this application is within a range of <NUM> millimeter to <NUM> millimeters. This is favorable for implementing lightness and thinness of the display screen <NUM> and the terminal <NUM>.

Optionally, the optical membrane assembly <NUM> is bonded to the optical conversion layer <NUM> by using a bonding layer <NUM>. The bonding layer <NUM> fastens the optical membrane assembly <NUM> and the optical conversion layer <NUM> together, and a connection relationship is reliable. The bonding layer <NUM> may include diffusion particles. A proportion of the diffusion particles is within a range of <NUM>-<NUM>%, to meet both a transparency requirement and a light mixing requirement. A diameter of the diffusion particles added into the bonding layer <NUM> is within a range of <NUM> nanometers to <NUM> micrometers. A material of the diffusion particles includes but is not limited to polymethyl methacrylate (polymethyl methacrylate, PMMA), silicon dioxide, metal ions, and the like. A difference between a refractive index of scattering particles and a refractive index of adhesive of the bonding layer <NUM> is within a range of <NUM> to <NUM>. After the diffusion particles are added, a light transmittance of the bonding layer <NUM> is greater than <NUM>%. Adhesive of the bonding layer <NUM> may be fluid, and formed through slit coating (Slit Coating) or spraying. Alternatively, adhesive of the bonding layer <NUM> may be a plate viscoelastic body. Certainly, in another implementation, there may be no diffusion particles in the bonding layer <NUM>.

Optionally, the backlight module <NUM> further includes a backplane <NUM>, a plastic frame <NUM>, and square-shaped adhesive <NUM>. The plastic frame <NUM> is connected around the backplane <NUM>, to jointly encircle an accommodation space <NUM>. The substrate <NUM>, the optical conversion layer <NUM>, and the optical membrane assembly <NUM> are all accommodated in the accommodation space <NUM>. The square-shaped adhesive <NUM> bonds the optical membrane assembly <NUM> and the plastic frame <NUM>. In this case, the optical membrane assembly <NUM> is mounted on the optical conversion layer <NUM> in a spaced manner, and there is an air gap <NUM> between the optical membrane assembly <NUM> and the optical conversion layer <NUM>.

Optionally, as shown in <FIG>, the optical membrane assembly <NUM> includes a plurality of light mixing thin films <NUM>. The light mixing thin films <NUM> are configured to transmit some light and reflect the other light. The plurality of light mixing thin films <NUM> are located on a surface of the optical membrane assembly <NUM> facing the optical conversion layer. The plurality of light mixing thin films <NUM> are aligned with the plurality of spot light sources <NUM> in a one-to-one correspondence. In other words, the plurality of light mixing thin films <NUM> are located right above the plurality of spot light sources <NUM> in a one-to-one correspondence. The plurality of light mixing thin films <NUM> can further reduce the luminance in the central area of the plurality of spot light sources <NUM>, to achieve the light mixing effect, thereby achieving better light emission evenness for the backlight module <NUM>. The plurality of light mixing thin films <NUM> and the plurality of membranes <NUM> may use same or similar materials and have same or similar structures.

According to the claimed invention, as shown in <FIG>, the optical membrane assembly <NUM> includes a first prism film <NUM>, a diffusion film (Diffuser) <NUM>, and a second prism film <NUM> that are stacked in sequence. The first prism film <NUM> is located between the optical conversion layer <NUM> and the diffusion film <NUM>, and the first prism film <NUM> and the second prism film <NUM> cooperate with each other to brighten passing light. In this case, the plurality of light mixing thin films <NUM> are located on a side of the first prism film <NUM> facing the optical conversion layer <NUM>.

The diffusion film <NUM> is configured to provide an even surface light source for the backlight module <NUM>. A material having a high light transmittance, for example, polyethylene terephthalate (Polyethylene terephthalate, PET)/polycarbonate (Polycarbonate, PC)/polymethyl methacrylate (Polymethyl methacrylate, PMMA), needs to be selected as a base material of the diffusion film <NUM>. The diffusion film <NUM> is mainly made by adding chemical grains as scattering particles into the base material of the diffusion film <NUM>. However, in an existing diffusion board, micro-particles are distributed between resin layers. As a result, when passing through the diffusion film <NUM>, light constantly passes through two media having different refractive indexes. In this process, the light is refracted, reflected, and scattered, resulting in an optical diffusion effect. The diffusion film <NUM> includes an antistatic coating layer, a PET base material, and a diffusion layer that are stacked in sequence in a light emission direction. The diffusion film <NUM> may be a scattered particle-type diffusion film, a bulk diffusion film, or the like.

The first prism film <NUM> and the second prism film <NUM> each are a transparent plastic thin film with a thickness ranging from <NUM> micrometers to <NUM> micrometers. A layer of prism structure is overlaid evenly and neatly on an upper surface of the thin film. The first prism film <NUM> and the second prism film <NUM> are configured to improve angular distribution of light, so that diverged light is converged to an axial angle, that is, a front view angle. This improves axial luminance without increasing an overall emergent luminous flux, thereby implementing brightening. A membrane material of the first prism film <NUM> and the second prism film <NUM> each may be a single-layer prism film or a double-layer bonding prism film (an angle between the two layers may be changed as required). A prism shape may be a regular strip prism, a pyramid, a frustum, a cone, or the like. Prism patterns may use different parameters, for example, different angles (for example, vertex angles of <NUM>° to <NUM>°); a cycle is changed as required; or the like.

Optionally, the first prism film <NUM> and the diffusion film <NUM> are bonded by using a transparent bonding layer <NUM>, and the diffusion film <NUM> and the second prism film <NUM> are bonded by using a transparent bonding layer <NUM>. The transparent bonding layer <NUM> may be made of optical silica gel or an ultraviolet-cured glue material. Diffusion particles may be added into the transparent bonding layer <NUM> to enhance the light mixing effect. Adhesive of the transparent bonding layer <NUM> may be fluid, and formed through slit coating (Slit Coating) or spraying. Alternatively, adhesive of the transparent bonding layer <NUM> may be a plate viscoelastic body. Certainly, in another implementation, alternatively, the first prism film <NUM> and the diffusion film <NUM> may be fastened by using adhesive in a periphery, and the diffusion film <NUM> and the second prism film <NUM> may be fastened by using adhesive in a periphery, to implement spaced mounting. In this case, there is an air gap <NUM> between the first prism film <NUM> and the diffusion film <NUM>, and there is an air gap <NUM> between the diffusion film <NUM> and the second prism film <NUM>.

In another implementation, not according to the claimed invention, a combination manner of the optical membrane assembly <NUM> may be: a diffusion film + a prism film, or a diffusion film + a prism film + a diffusion film + a prism film. A topmost layer that is of the optical membrane assembly <NUM> and that is away from the optical conversion layer <NUM> is a prism film. Film layers of the optical membrane assembly <NUM> are bonded to each other by using a bonding material layer or fastened through spaced mounting.

It can be understood that, in this embodiment of this application, diffusion particles are added into each bonding material layer to enhance the light mixing effect. In this embodiment of this application, the bonding material layers include but are not limited to the optical clear adhesive, the bonding layer <NUM>, the transparent bonding layer <NUM>, and the like. A diameter of the diffusion particles is within a range of <NUM> nanometers to <NUM> micrometers. A mixing proportion of the diffusion particles is within a range of <NUM>-<NUM>%. The diffusion particles and the diffusion powder <NUM> may be made of a same material and have a same size, to simplify material types of the backlight module <NUM>, thereby reducing costs of the backlight module <NUM>.

With reference to <FIG>, in a specific embodiment, the first implementation to the fifth implementation of the light mixing member <NUM>, the second implementation of the optical conversion layer <NUM>, and the plurality of implementations of the optical membrane assembly <NUM> may be randomly combined.

The following describes a fabrication method with reference to the specific embodiments of the backlight module <NUM>.

Step <NUM><NUM>: Referring to <FIG> and <FIG>, mount a plurality of spot light sources <NUM> onto a substrate <NUM>.

The substrate <NUM> is provided, the plurality of spot light sources <NUM> are fastened onto the substrate <NUM> according to a particular arrangement rule, and an electrical connection is established.

Step <NUM><NUM>: Referring to <FIG> and <FIG>, process an optical conversion layer <NUM> and a light mixing member <NUM>.

Solution <NUM>: Referring to <FIG>, for a combination of the first implementation of the light mixing member <NUM> and the first implementation of the optical conversion layer <NUM>:
Provide a half-cured membrane or liquid adhesive that mainly includes optical silica gel or ultraviolet-cured glue and in which a phosphor <NUM> and a diffusion powder <NUM> are evenly mixed; place, at a mold fastening position of an injection molding (Molding) device or a hot-pressing device, the substrate <NUM> to which the plurality of spot light sources <NUM> are assembled in step <NUM>, and then overlay the half-cured membrane or the liquid adhesive above the substrate <NUM> or at a position corresponding to a mold; and then press-fit the membrane material onto the substrate <NUM> in through hot-pressing and vaccumization, to form the optical conversion layer <NUM> that completely encloses the plurality of spot light sources <NUM>.

Solution <NUM>: Referring to <FIG>, for a combination of the first implementation of the light mixing member <NUM> and the second implementation of the optical conversion layer <NUM>:.

Solution <NUM>: Referring to <FIG>, for a combination of the first implementation of the light mixing member <NUM> and the third implementation of the optical conversion layer <NUM>:.

Solution <NUM>: Referring to <FIG>, for a combination of the first implementation of the light mixing member <NUM> and the fourth implementation of the optical conversion layer <NUM>:.

Solution <NUM>: Referring to <FIG> and <FIG> to <FIG>, for a combination of the second implementation of the light mixing member <NUM> and the first implementation of the optical conversion layer <NUM>:.

Solution <NUM>: Referring to <FIG>, for a combination of the third implementation of the light mixing member <NUM> and the first implementation of the optical conversion layer <NUM>:.

Solution <NUM>: Referring to <FIG> and <FIG>, for a combination of the third implementation of the light mixing member <NUM> and the second implementation of the optical conversion layer <NUM>:.

On a basis of the steps in solution <NUM>, the following step is added after the first step, the second step, or the third step in solution <NUM>: providing a material having both transmission and reflection functions; designing a particular opening by using a mask; forming a thin film on a surface of the packaging layer <NUM>, a surface of the conversion layer <NUM>, or a surface of the protection layer <NUM> by using a spraying or coating technology or by using a metal stencil printing or silk-screen printing technology; and forming a plurality of membranes <NUM> by heating and baking or by ultraviolet curing. In this case, the plurality of membranes <NUM> are located between the packaging layer <NUM> and the conversion layer <NUM>, between the conversion layer <NUM> and the protection layer <NUM>, or on a side that is of the protection layer <NUM> and that is away from the conversion layer <NUM>.

Solution <NUM>: Referring to <FIG> and <FIG>, for a combination of the third implementation of the light mixing member <NUM> and the third implementation of the optical conversion layer <NUM>:
On a basis of the steps in solution <NUM>, the following step is added after the first step or the second step in solution <NUM>: providing a material having both transmission and reflection functions; designing a particular opening by using a mask; forming a thin film on a surface of the first conversion sublayer <NUM> or a surface of the second conversion sublayer <NUM> by using a spraying or coating technology or by using a metal stencil printing or silk-screen printing technology; and forming a plurality of membranes <NUM> by heating and baking or by ultraviolet curing. In this case, the plurality of membranes <NUM> are formed between the first conversion sublayer <NUM> and the second conversion sublayer <NUM> or on a side that is of the second conversion sublayer <NUM> and that is away from the first conversion sublayer <NUM>.

Solution <NUM>: Referring to <FIG> and <FIG>, for a combination of the third implementation of the light mixing member <NUM> and the fourth implementation of the optical conversion layer <NUM>:
On a basis of the steps in solution <NUM>, the following step is added after the first step or the second step is completed: providing a material having both transmission and reflection functions; designing a particular opening by using a mask; forming a thin film on a surface of the plurality of conversion thin films <NUM> or a surface of the packaging element <NUM> by using a spraying or coating technology or by using a metal stencil printing or silk-screen printing technology; and forming a plurality of membranes <NUM> by heating and baking or by ultraviolet curing. In this case, the plurality of membranes <NUM> are formed between the conversion thin films <NUM> and the packaging element <NUM> or on a surface that is of the packaging element <NUM> and that is away from the conversion thin films <NUM>.

Solution <NUM>: Referring to <FIG>, for a combination of the fourth implementation of the light mixing member <NUM> and the first implementation of the optical conversion layer <NUM>:.

Solution <NUM>: Referring to <FIG> and <FIG>, for a combination of the fourth implementation of the light mixing member <NUM> and the second implementation of the optical conversion layer <NUM>:
On a basis of the steps in solution <NUM>, the following step is added after the first step, the second step, or the third step is completed: forming, on a surface of the optical conversion layer <NUM> or a surface of a transparent film layer through imprinting, etching, diamond cutting, or the like, a micro structural block <NUM> for optical diffusion. In this case, the micro structural block <NUM> is located between the packaging layer <NUM> and the conversion layer <NUM>, between the conversion layer <NUM> and the protection layer <NUM>, or on a side that is of the protection layer <NUM> and that is away from the conversion layer <NUM>.

Solution <NUM>: Referring to <FIG> and <FIG>, for a combination of the fourth implementation of the light mixing member <NUM> and the third implementation of the optical conversion layer <NUM>:
On a basis of the steps in solution <NUM>, the following step is added after the first step or the second step is completed: forming, on a surface of a green phosphor layer or a surface of a red phosphor layer through imprinting, etching, diamond cutting, or the like, a layer of micro structural block <NUM> for optical diffusion. In this case, the micro structural block <NUM> is formed between the first conversion sublayer <NUM> and the second conversion sublayer <NUM> or on a side that is of the second conversion sublayer <NUM> and that is away from the first conversion sublayer <NUM>.

Solution <NUM>: Referring to <FIG> and <FIG>, for a combination of the fourth implementation of the light mixing member <NUM> and the fourth implementation of the optical conversion layer <NUM>:
On a basis of the steps in solution <NUM>, the following step is added after the first step or the second step is completed: forming, on a surface of the optical conversion layer <NUM> or a surface of a transparent film layer through imprinting, etching, diamond cutting, or the like, a layer of micro structural block <NUM> for optical diffusion. In this case, the micro structural block <NUM> is formed between the conversion thin films <NUM> and the packaging element <NUM> or on a surface that is of the packaging element <NUM> and that is away from the conversion thin films <NUM>.

Solution <NUM>: Referring to <FIG> and <FIG> to <FIG>, for a combination of the fifth implementation of the light mixing member <NUM> and the first implementation to the fourth implementation of the optical conversion layer <NUM>:.

Step <NUM><NUM>: Referring to <FIG>, perform cutting and forming.

Cutting and molding are performed on a semi-finished product of the processed optical conversion layer <NUM> and the light mixing member <NUM> through laser cutting, mechanical cutting, or stamping, to form a surface light source component having a required product appearance.

Step <NUM><NUM>: Referring to <FIG> and <FIG>, process an optical membrane assembly <NUM>.

Claim 1:
A backlight module (<NUM>), comprising:
a substrate (<NUM>), a plurality of spot light sources (<NUM>), an optical conversion layer (<NUM>) and a light mixing member (<NUM>), wherein:
the plurality of spot light sources (<NUM>) are fastened onto the substrate (<NUM>) in a mutually spaced manner;
the optical conversion layer (<NUM>) is stacked on the substrate (<NUM>) and covers the plurality of spot light sources (<NUM>); the optical conversion layer (<NUM>) is configured to convert, into a white surface light source, light emitted by the plurality of spot light sources (<NUM>), wherein the optical conversion layer (<NUM>) comprises a packaging layer (<NUM>), a conversion layer (<NUM>) including phosphor and/or quantum dots, and a protection layer (<NUM>), the packaging layer (<NUM>) is made of a transparent material, the packaging layer (<NUM>) is in contact with the substrate (<NUM>) and encloses the plurality of spot light sources (<NUM>), the protection layer (<NUM>) located on a side that is of the conversion layer (<NUM>) and that is away from the packaging layer (<NUM>) and the conversion layer (<NUM>) covers a side that is of the packaging layer (<NUM>) and that is away from the substrate (<NUM>);
the light mixing member (<NUM>) comprises a plurality of diffusion powders (<NUM>) exclusively distributed in the packaging layer (<NUM>) and the protection layer (<NUM>); and the light mixing member (<NUM>) is configured to mix the light;
and further comprising
an optical membrane assembly (<NUM>) located on a side that is of the optical conversion layer (<NUM>) and that is away from the substrate (<NUM>) and configured to mix and brighten passing light and
comprising a first prism film (<NUM>), a diffusion film (<NUM>), and a second prism film (<NUM>) that are stacked, wherein the first prism film (<NUM>) is located between the optical conversion layer (<NUM>) and the diffusion film (<NUM>) and the first prism film (<NUM>) and the second prism film (<NUM>) cooperate with each other to brighten passing lights.