Flexible laser backlight plate and preparation method

Abstract

The invention discloses a flexible laser backlight plate and a preparation method, and relates to the technical field of laser display, the flexible laser backlight plate comprises a volume scattering particle composite layer, a reflecting layer, a light guide main body layer and a connecting end, and an optical fiber side light leakage optical fiber group is arranged in the light guide main body layer; the connecting end is arranged at one end of the backlight plate and provided with a light inlet end face corresponding to the light inlet end of the optical fiber side light leakage optical fiber set. In the optical fiber side light leakage optical fiber group, the side leakage structures of the optical fibers are non-uniformly distributed along the length direction of the optical fibers, and preset brightness distribution can be formed in the light guide main body layer, so that the preset brightness distribution can be formed and kept on the light emitting surface of the flexible laser backlight plate in a bent or flattened state; the problems of light path change and uneven brightness caused by flexible deformation are effectively solved.

Description

Technical Field

[0001] This invention relates to the field of laser display technology, and in particular to a flexible laser backlight panel and its preparation method. Background Technology

[0002] In the era of consumer electronics where visual experience has become a core requirement, the direction of display technology upgrades is becoming increasingly clear. On the one hand, users' pursuit of picture quality has moved from high definition to "ultimate reproduction." Laser display technology, with its extremely narrow wavelength and high color purity, can provide a wide color gamut display effect covering the BT.2020 color gamut. Coupled with its advantages of high brightness and high contrast, it has become the core direction of the next generation of display technology.

[0003] On the other hand, with the popularization of products such as foldable phones, flexible wearable devices, and flexible automotive displays, "flexibility" has become the key to innovation in display device form factors. This requires backlight panels to have reliable bending performance and ultra-thin structural designs to adapt to diverse application scenarios.

[0004] However, the existing display technology field suffers from significant technological fragmentation and core pain points, and a technical solution that can simultaneously satisfy both "high-definition laser display" and "flexible form factor" has not yet been formed. Specifically: Existing laser backlight technologies (such as CN104776356B, CN101382699B, CN107238970B, CN216118304U, etc.) are all designed with rigid structures as the core. Although they can achieve the basic functions of laser backlighting, they have limitations that are difficult to overcome.

[0005] Existing rigid laser backlight systems (such as the laser backlight system in CN101382699B) have complex optical structures and large volumes, and are mainly used in large-size devices such as projectors. They are difficult to miniaturize and make ultra-thin designs, and cannot meet the requirements for thinness and lightness of small and medium-sized consumer electronics such as mobile phones and tablets.

[0006] While some rigid solutions attempt to address the issues of uniform light distribution and light energy utilization in laser backlighting (such as CN206292413U filling the light guide tube with scattering particles and CN216118304U achieving color homogenization through a conical reflective surface), they do not address the speckle problem unique to lasers. Furthermore, their rigid structural designs completely fail to consider the requirements for light transmission stability and component stress adaptation in flexible scenarios. Even relatively intricate laser backlight modules still employ rigid substrate designs, making bending impossible and failing to develop mature flexible adaptation solutions.

[0007] Existing flexible display technologies (such as CN212160281U and CN210244011U) are all based on LED light source design. Although they achieve flexible form, they cannot give full play to the image quality advantages of laser display and have inherent technical limitations.

[0008] The interface of flexible LED displays only needs to meet the low-precision docking and low-stress requirements of LED light strips, and cannot withstand the precise positioning and repeated insertion and removal stress required for laser coupling, thus it cannot be adapted to the application scenarios of laser light sources.

[0009] In summary, in existing technologies, the "high image quality advantage of laser backlighting" and the "form advantage of flexible displays" are disconnected. Rigid laser backlighting technology cannot overcome form limitations, and flexible LED display technology cannot overcome image quality bottlenecks. Furthermore, neither of them has solved the problem of "coordinated adaptation between laser and flexible structure". Summary of the Invention

[0010] This invention provides a flexible laser backlight panel and its preparation method, which enables the light-emitting surface of the flexible laser backlight panel to form and maintain a preset brightness distribution when it is bent or flat, effectively solving the problems of light path change and uneven brightness caused by flexible deformation.

[0011] To address the above problems, the present invention provides a flexible laser backlight panel, comprising: Volume scattering particle composite layer; Reflective layer; The light guide body layer contains a fiber optic leak-out fiber group on the fiber side. A connection end is provided at one end of the backlight panel, and the connection end is provided with an input end face corresponding to the input end of the optical fiber leakage fiber group on the optical fiber side. In the optical fiber side-leakage optical fiber group, the side-leakage structure of the optical fiber is non-uniformly distributed along its length direction to form a preset brightness distribution within the light guiding body layer.

[0012] The flexible laser backlight panel provided by this invention has, but is not limited to, the following beneficial effects compared to existing technologies: By embedding an optical fiber array with a non-uniform side-leaking structure into a flexible light guide layer, this solution can actively and precisely pre-set and form the desired brightness distribution within the light guide layer. This design fundamentally solves the core problem of severe brightness unevenness caused by random changes in the optical path when traditional flexible backlights are bent or deformed, ensuring the consistency of optical performance of the backlight in dynamic flexible applications.

[0013] The synergistic design of the volume scattering particle composite layer and the reflective layer constitutes a highly efficient light extraction and recovery system. In particular, the gradient-designed volume scattering layer guides light to be scattered forward gradually and uniformly, while the high-reflective layer reflects the scattered light back into the system for reuse, thus jointly achieving high light energy utilization and excellent surface light source uniformity.

[0014] The connector, by forming a rigid or semi-rigid structure at the end of the flexible backlight panel, provides a precise and robust mechanical and optical docking platform for the laser source. This effectively solves the coupling problem of long-term stable alignment between flexible devices and rigid laser sources, ensuring light input efficiency and reducing the risk of performance fluctuations or failures caused by optical path misalignment due to vibration or bending.

[0015] Preferably, the volume scattering particle composite layer is a gradient scattering microstructure layer, wherein the concentration and / or particle size of the scattering particles vary in a gradient along the thickness direction, and the scattering intensity on the side closer to the light guide body layer is lower than that on the side closer to the light emitting surface.

[0016] Preferably, the fiber optic side-leakage optical fiber group comprises multiple independent optical fibers, wherein the side-leakage structural parameters of the fiber optic side-leakage optical fiber group include side-leakage aperture, density, or number of cycles.

[0017] Preferably, in the optical fiber side leakage optical fiber group, the side leakage intensity of the optical fiber located in the preset edge region is greater than that of the optical fiber located in the preset center region.

[0018] Preferably, the reflective layer is a flexible high-reflectivity film, which is attached to the back surface of the light guide body layer; Or a high-reflectivity coating formed directly on the back surface of the light guide body layer.

[0019] Preferably, the connection end is formed by partially curing or coating the end of the light guide body layer with a composite rigid material to form a rigid or semi-rigid docking structure.

[0020] Preferably, a microscale interlocking structure is provided between the light guiding main body layer and the volume scattering particle composite layer, and between the light guiding main body layer and the reflective layer. The interlocking structure includes a micron-scale bump array disposed on the surface of the light guiding main body layer, and a micron-scale groove array correspondingly disposed on the bonding surface of the volume scattering particle composite layer and the reflective layer, with the bumps and grooves being interference fit.

[0021] Preferably, this application also provides a method for preparing a flexible laser backlight panel, comprising the following steps: Provide a mold, and fix the fiber optic leakage fiber group in the mold according to the design arrangement; Uncured transparent flexible polymer material is poured into the mold to cover the light-leaking fiber group on the optical fiber side and then cured to form the light guiding body layer; The volume scattering particle composite layer is formed on the light-emitting surface side of the light-guiding main body layer; The reflective layer is formed on the backlight side of the light guide body layer; One end of the light guide body layer is locally hardened or a rigid component is added to form the connection end, and the light-incoming end face is polished.

[0022] Preferably, the volume scattering particle composite layer is formed on the light-emitting surface side of the light-guiding main body layer, specifically as follows: An uncured colloidal mixture containing scattering particles is coated onto the light-emitting side of the light guide body layer, and then cured. Alternatively, a flexible thin film containing scattering particles can be prepared in advance and then bonded to the light-emitting side of the light-guiding main body layer with optical adhesive.

[0023] Preferably, one end of the light guide body layer is processed to form the connection end, specifically as follows: The end region is locally heated, irradiated with ultraviolet light, or chemically treated to cause local hardening. Alternatively, a sleeve or frame made of a rigid material may be laminated at this end. Attached Figure Description

[0024] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0025] Figure 1 This is a schematic diagram of an exploded structure of a flexible laser backlight panel according to an embodiment of the present invention. Figure 1 ; Figure 2 This is a schematic diagram of an exploded structure of a flexible laser backlight panel according to an embodiment of the present invention. Figure 2 ; Figure 3 This is a schematic diagram of the internal structure of the light guide body layer according to an embodiment of the present invention; Figure 4 This is a schematic diagram of the connection between the light-guiding main body layer and the volume scattering particle composite layer in an embodiment of the present invention; Figure 5 This is a schematic flowchart of a method for preparing a flexible laser backlight panel according to an embodiment of the present invention.

[0026] Explanation of reference numerals in the attached figures: 100, Volume scattering particle composite layer; 200, Reflective layer; 300, Light guiding main body layer; 310, Fiber optic side leakage fiber group; 311, Fiber optic cable; 400, Connecting end; 500, Interlocking structure; 510, Micrometer-level bump array; 520, Micrometer-level groove array. Detailed Implementation

[0027] To make the objectives, technical solutions, and advantages of this application clearer, the technical solutions in the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings showing multiple embodiments according to this application. It should be understood that the described embodiments are only a part of the embodiments of this application, and not all of the embodiments. All other embodiments obtained by those skilled in the art based on the embodiments described in this application without creative effort will fall within the scope of protection of this application.

[0028] Unless otherwise defined, all technical and scientific terms used in this application have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains; the terminology used in the description of this application is for the purpose of describing specific embodiments only and is not intended to limit this application; the terms "comprising," "including," "having," "containing," etc., in the description, claims, and accompanying drawings of this application are open-ended terms. Therefore, "comprising," "including," or "having" refers to, for example, a method or apparatus having one or more steps or elements, but is not limited to having only these one or more elements. The terms "first," "second," etc., in the description, claims, or accompanying drawings of this application are used to distinguish different objects, not to describe a specific order or hierarchy. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, unless otherwise stated, "a plurality of" means two or more.

[0029] In the description of this invention, it should be understood that the terms "upper," "lower," "left," "right," "front," "rear," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0030] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," "linking," and "attachment" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal communication between two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0031] It should be emphasized that when the term "comprising / including" is used in this specification, it is used to explicitly indicate the presence of the stated feature, integer, step, or component, but does not exclude the presence or addition of one or more other features, integers, steps, parts, or groups of features, integers, steps, or parts.

[0032] like Figures 1 to 4 As shown in the figure, an embodiment of the present invention provides a flexible laser backlight panel, including a volume scattering particle composite layer 100, a reflective layer 200, a light guiding main layer 300, and a connecting end 400. The light guiding main layer 300 is provided with an optical fiber side leakage fiber group 310. The connecting end 400 is disposed at one end of the backlight panel, and the connecting end 400 is provided with a light-incoming end face corresponding to the light-incoming end of the optical fiber side leakage fiber group 310. In the optical fiber side leakage fiber group 310, the side leakage structure of the optical fiber 311 is non-uniformly distributed along its length direction to form a preset brightness distribution within the light guiding main layer 300.

[0033] In this embodiment, the light guide body layer 300 is made of transparent flexible polymer material, and the internally embedded optical fiber side leakage optical fiber group 310 is composed of multiple independent side leakage optical fibers 311. Each optical fiber 311 has a non-uniformly distributed side leakage structure along its length direction, so that the laser transmitted from the optical fiber 311 leaks laterally at different positions with different intensities, thereby forming a preset brightness distribution in the light guide body layer 300.

[0034] The transparent flexible polymer materials mentioned above include polyurethane acrylate, silicone, or thermoplastic polyurethane.

[0035] The brightness distribution mainly includes a dark center and bright edges, or a specific patterned brightness distribution.

[0036] The connector 400 is located at one end of the backlight panel, and its light-inlet end face is precisely aligned with the light-inlet end of the fiber optic leakage fiber group 310 on the fiber side. It is used to couple an external laser source. To ensure docking stability, the connector 400 is subjected to local ultraviolet curing treatment to form a rigid area at the end of the light guide body layer 300; or an epoxy resin-coated hard metal / ceramic sleeve is used to form a semi-rigid docking structure.

[0037] Its external light source includes lasers, such as edge-emitting lasers or VCSEL arrays.

[0038] In this embodiment, the volume scattering particle composite layer 100 is a gradient scattering microstructure layer, in which the concentration and / or particle size of the scattering particles vary in a gradient along the thickness direction, and the scattering intensity on the side closer to the light guide body layer 300 is lower than that on the side closer to the light emitting surface.

[0039] This gradient design ensures that the laser light guided within the main light-guiding layer 300 undergoes weaker scattering upon entering the volume scattering particle composite layer 100, reducing initial light loss and inhomogeneity. As the light propagates towards the light-emitting surface, the scattering intensity gradually increases, ultimately achieving efficient and uniform light emission, effectively improving light energy utilization and the uniformity of the displayed image. Simultaneously, the scattering particles can be selected from PMMA microspheres, Si... Particles or Ti The refractive index of the nanoparticles is controlled to be between 0.1 and 0.5, and the preset scattering efficiency can be achieved by adjusting the Mie scattering effect.

[0040] In this embodiment of the application, the fiber optic side-leakage optical fiber group 310 includes multiple independent optical fibers 311, wherein the side-leakage structural parameters of the fiber optic side-leakage optical fiber group 310 include side-leakage aperture, density or period.

[0041] Different optical fibers 311 can be configured with differentiated side-leakage structure parameters according to the target brightness distribution requirements. For example, the optical fiber 311 located in the central area of ​​the backlight panel can use a smaller side-leakage aperture and a lower density to reduce light leakage intensity, while the optical fiber 311 in the edge area can use a larger side-leakage aperture and a higher density to enhance the light output in the edge area. This zoned control method achieves brightness uniformity across the entire backlight panel's light-emitting surface. In addition, the periodic design of the side-leakage structure can be matched with the resolution requirements of the display screen to avoid visual interference such as moiré patterns.

[0042] In this embodiment of the application, in the optical fiber side leakage optical fiber group 310, the side leakage intensity of the optical fiber 311 located in the preset edge region is greater than that of the optical fiber 311 located in the preset center region.

[0043] This design effectively compensates for the edge brightness attenuation problem commonly found in traditional backlights by enhancing the side leakage intensity of fiber 311 in the edge region. When the backlight is in a bent state, the impact of the change in optical path in the edge region on the brightness uniformity can be further offset by the preset side leakage intensity gradient, ensuring that a stable brightness distribution can be maintained in both bent and flat states.

[0044] In this embodiment, the reflective layer 200 is a flexible high-reflection film, which is attached to the back surface of the light guide body layer 300; or a high-reflection coating is directly formed on the back surface of the light guide body layer 300.

[0045] Flexible high-reflectivity films can be made of aluminized PET film, silver nanowire flexible reflective film, or white flexible silicone sheet, with a reflectivity of not less than 95% and mechanical reliability of more than 10,000 cycles of bending with a bending radius of less than 5mm. The directly formed high-reflectivity coating can be made by mixing Al2O3 / Ag composite slurry or TiO2 / mica pearlescent pigment with a flexible resin matrix and then coating and curing it. The coating thickness is controlled at 5-20μm to ensure high reflectivity while avoiding coating cracking.

[0046] In this embodiment, the connection end 400 is formed by partially curing or coating the end of the light guide body layer 300 with a composite rigid material to form a rigid or semi-rigid docking structure.

[0047] This rigid or semi-rigid docking structure effectively improves the positioning accuracy and mechanical strength when coupling with an external laser light source. Even when the backlight panel is bent or subjected to vibration, it can maintain stable alignment between the light-inlet end face and the laser light source output end, reducing light efficiency loss or display flicker caused by optical path misalignment. For example, when using local UV curing, the shape and size of the curing area can be controlled by a mask, allowing the connection end 400 to maintain a reliable connection with the flexible part of the light guide body layer 300 while forming a docking interface with specific rigidity. The sleeve or frame covered with composite rigid material can be further precision-machined to form standardized interface dimensions, facilitating rapid assembly and replacement with different types of laser light source modules, thus improving the compatibility and maintainability of the flexible laser backlight panel in actual production and application.

[0048] In this embodiment, a microscale interlocking structure 500 is provided between the light guide body layer 300 and the volume scattering particle composite layer 100, and between the light guide body layer 300 and the reflective layer 200. The interlocking structure 500 includes a micron-scale bump array 510 disposed on the surface of the light guide body layer 300, and a micron-scale groove array 520 correspondingly disposed on the bonding surface of the volume scattering particle composite layer 100 and the reflective layer 200, with the bumps and grooves being interference-fitted.

[0049] This microscale interlocking structure 500, through the interference fit between the micron-scale bump array 510 and the micron-scale groove array 520, can significantly enhance the bonding strength at the interlayer interface, effectively solving the interlayer delamination problem that may occur during repeated bending of the flexible backlight panel. The diameter of the micron-scale bump array 510 is typically controlled at 5-50 μm, the height at 2-20 μm, and the spacing between adjacent bumps at 10-100 μm. Its specific size and distribution density can be optimized according to the material properties and bonding requirements of different layers. For example, at the interface between the light guide body layer 300 and the volume scattering particle composite layer 100, considering that both are flexible polymer materials, a smaller diameter and higher density bump array can be used to provide sufficient bonding force while reducing interference with light transmission between layers. At the interface between the light guide body layer 300 and the reflective layer 200, since the reflective layer 200 may be a thin film or coating structure, the bump size can be appropriately increased and the density reduced to avoid damaging the integrity of the reflective layer 200. This interlocking structure 500 not only enhances the physical bonding strength, but also promotes the uniform distribution of interlayer stress by increasing the interface contact area. Thus, under dynamic mechanical actions such as bending and stretching, it maintains the structural stability and optical performance consistency of each functional layer, further extending the service life and reliability of the flexible laser backlight panel.

[0050] In this embodiment of the application, a method for preparing a flexible laser backlight panel is also provided, the method comprising: A mold is provided, and the fiber-side leakage fiber group 310 is arranged and fixed in the mold according to the design. Uncured transparent flexible polymer material is poured into the mold to cover the optical fiber side leakage fiber group 310 and then cured to form the light guiding body layer 300. The volume scattering particle composite layer 100 is formed on the light-emitting surface side of the light guide body layer 300; The reflective layer 200 is formed on the backlight side of the light guide body layer 300; One end of the light guide body layer 300 is locally hardened or a rigid component is added to form the connection end 400, and the light-incoming end face is polished.

[0051] In the above method, when fixing the fiber optic side-leaking fiber group 310, a pre-set positioning slot or vacuum adsorption device can be used in the mold to ensure that multiple fibers 311 are accurately fixed according to the designed spacing and arrangement, and the positioning error is controlled within ±5μm. For non-uniformly distributed side-leaking fiber 311, a visual recognition system is needed to assist in calibrating its axial angle to ensure that the side-leaking light direction matches the light transmission path of the light guiding main layer 300. Before casting the transparent flexible polymer material, the mold cavity needs to be plasma surface treated or coated with a fluorosilane release agent to reduce the interfacial adhesion between the material and the mold. At the same time, the material is degassed in a vacuum environment at 60-80℃ for 30-60 minutes to remove air bubbles and avoid light scattering loss. The curing process adopts a gradient heating method, for example, pre-curing at 40℃ for 2 hours and then heating to 70℃ for complete curing for 4 hours to reduce material deformation or cracking caused by internal stress.

[0052] When forming a bulk scattering particle composite layer 100 on the light-emitting side of the light-guiding main layer 300, micro-nano coating technology, such as electrostatic spray deposition or slot coating, can be used. When electrostatic spray deposition is used, the polymer solution containing scattering particles is atomized into micron-sized droplets under the action of a 10-30kV high-voltage electric field and uniformly deposited on the surface of the light-guiding main layer 300. Gradient concentration distribution is achieved by controlling the spray rate and the substrate moving speed. If slot coating is used, a slurry with different particle concentrations is delivered to the coating head through a multi-channel feeding system. A continuous concentration gradient is formed in the wet film by utilizing the laminar diffusion effect. The thickness of the coated wet film is controlled at 20-50μm. After hot air drying at 80-100℃ and UV curing, a composite layer is formed.

[0053] When forming the reflective layer 200, for flexible high-reflectivity films, a hot-press bonding process is used, maintaining the film at 60-80℃ and 0.5-1MPa pressure for 30-60 seconds to fully integrate the film layer with the microscale interlocking structure 500 on the surface of the light guide body layer 300. For directly coated high-reflectivity coatings, the reflective paste is applied to the back surface of the light guide body layer 300 using a comma-shaped scraper, with the wet film thickness controlled at 10-30μm. After coating, it is first pre-dried by infrared, and then cured by ultraviolet or thermal curing to form the coating. During the curing process, a tension of 0.1-0.3MPa needs to be applied to the substrate to prevent the coating from shrinking and wrinkling.

[0054] When performing local hardening treatment on the end of the light guide body layer 300, if ultraviolet curing is used, an ultraviolet laser with a wavelength of 365nm is used to scan and irradiate the 5-10mm area at the end through a mask, and the energy density is controlled at 1000-2000mJ / cm², so that the cross-linking degree of the material in this area reaches more than 85%, forming a rigid area with a Shore hardness of D60-D80; if composite rigid material is used for coating, epoxy resin and hard metal / ceramic sleeve are integrally molded through injection molding process, and the inner wall of the sleeve is roughened by micro-etching to enhance the bonding force with the light guide body layer 300. The injection pressure is controlled at 5-10MPa and the holding time is 20-30 seconds. After rough grinding with a diamond wheel, the light-gathering end face is then finely ground with 1000-grit and 2000-grit silicon carbide sandpaper. Finally, chemical mechanical polishing is performed with a colloidal silica polishing slurry with a particle size of 1-3μm to make the end face roughness Ra≤5nm and flatness≤1μm, so as to reduce Fresnel reflection loss during laser coupling.

[0055] In this embodiment of the application, the volume scattering particle composite layer 100 is formed on the light-emitting surface side of the light guide body layer 300. Specifically, an uncured colloidal mixture containing scattering particles is coated on the light-emitting surface side of the light guide body layer 300 and then cured; or, an independent flexible film containing scattering particles is prepared in advance and then bonded to the light-emitting surface side of the light guide body layer 300 with optical adhesive.

[0056] When coating the uncured colloidal mixture containing scattering particles onto the light-emitting side of the light guide layer 300, methods such as doctor blade coating, screen printing, or inkjet printing can be used. Doctor blade coating is suitable for large-area uniform coating. The wet film thickness is controlled by adjusting the gap between the doctor blade and the substrate. The coating speed is generally 0.3-1 m / s. After coating, it is cured in stages at 60-90℃ in a hot air oven, or a UV-Vis composite curing system is used to ensure that the colloid is fully cross-linked and the scattering particles are evenly distributed.

[0057] Screen printing utilizes screens of varying mesh counts to achieve selective coating of specific areas, making it particularly suitable for preparing composite layers with locally patterned scattering characteristics. Its ink viscosity is typically controlled between 1000-5000 mPa·s, and the clarity of pattern edges and thickness consistency are ensured through coordinated control of squeegee pressure and printing speed. Inkjet printing technology offers higher digital precision, depositing colloidal inks with varying concentrations of scattering particles point-by-point according to a preset grayscale image, forming a continuously varying gradient scattering layer. The printhead temperature is maintained at 40-60℃ to reduce ink viscosity, with an ejection frequency of 1-10 kHz and droplet volume of 5-20 pL. Multi-channel printheads enable simultaneous printing of various scattering particles or concentrations, achieving a layer thickness accuracy of ±1 μm.

[0058] When preparing independent flexible films containing scattering particles in advance, either casting or calendering processes can be used. Casting involves casting a mixture of scattering particles (40-60 wt%) and resin through a flat die onto a PET release film. After drying in an oven at 80-120°C to remove the solvent, the film is flattened using a calender, with the film thickness controlled at 10-50 μm. Calendering is suitable for thermoplastic resin systems. The scattering particles and resin are melt-blended in a twin-screw extruder, and then pressed into a film using a three-roll or five-roll calender. The calendering temperature is set according to the resin melting point, and the linear speed is 1-5 m / min. The film thickness and surface finish are controlled by adjusting the gap between the rollers and the rotational speed ratio.

[0059] Before lamination, the prepared independent film needs to undergo plasma activation treatment on its surface, with a power of 100-300W and a time of 30-120 seconds, to improve the adhesion strength with the optical adhesive. The optical adhesive can be an acrylic optical transparent adhesive with a thickness of 25-100μm. The lamination process is carried out in a vacuum laminator to avoid the generation of air bubbles and ensure that there are no interface optical defects between the film and the light guide body layer 300.

[0060] In this embodiment of the application, one end of the light guide body layer 300 is processed to form the connection end 400, specifically by: subjecting the end area to local heating, ultraviolet irradiation or chemical treatment to cause local hardening; or, by composite coating the end with a sleeve or frame made of a rigid material.

[0061] When performing localized heat hardening on the end region, laser scanning heating or directional hot air heating can be used. For laser scanning heating, a fiber optic 311 laser with a wavelength of 1064nm is selected. The laser beam is controlled by a galvanometer system to perform a spiral scan in a 5-15mm region at the end, with a scanning speed of 50-100mm / s and a laser power density of 5-15W / mm². This raises the material temperature in this region to 20-50℃ above the glass transition temperature and holds it for 30-60 seconds. Subsequently, it is allowed to cool naturally to room temperature, forming a hardened zone with a hardness gradient. The surface Shore hardness smoothly transitions from D50 at the edge to D85 at the center, avoiding stress concentration.

[0062] When the sleeve or frame is made of a rigid material with composite coating at the end, the sleeve material can be LCP liquid crystal polymer, PEEK polyether ether ketone or 304 stainless steel, and the frame can be made of glass fiber reinforced PA66 or magnesium aluminum alloy.

[0063] The above-disclosed embodiments are merely a few specific examples of the present invention. However, the embodiments of the present invention are not limited thereto, and any variations that can be conceived by those skilled in the art should fall within the protection scope of the present invention.

Claims

1. A flexible laser backlight panel, characterized in that, The application relates to a backlight panel, which comprises the following parts: a bulk scattering particle composite layer (100); a reflecting layer (200); a light guide main body layer (300) internally provided with a side leakage optical fiber (311) group (310); and a connecting end (400) arranged at one end of the backlight panel and provided with a light inlet end surface corresponding to a light inlet end of the side leakage optical fiber (311) group (310). The side leakage structure of the optical fiber (311) is non-uniformly distributed along the length direction of the optical fiber (311) so as to form a preset brightness distribution in the light guide main body layer (300). The bulk scattering particle composite layer (100) is a gradient scattering microstructure layer, the concentration and / or particle size of the scattering particles of which are gradiently changed along the thickness direction, and the scattering intensity of the side close to the light guide main body layer (300) is lower than that of the side close to the light outlet surface. The side leakage optical fiber (311) group (310) comprises a plurality of independent optical fibers (311), wherein the side leakage structure parameters of the side leakage optical fiber (311) group (310) include a side leakage aperture, density or period. The side leakage intensity of the optical fiber (311) located in a preset edge region is greater than that of the optical fiber (311) located in a preset central region. The reflecting layer (200) is a flexible high-reflection film attached to the backlight surface of the light guide main body layer (300).

2. The flexible laser backlight of claim 1, wherein, Or a high-reflection coating layer directly formed on the backlight surface of the light guide main body layer (300).

3. The flexible laser backlight of claim 1, wherein, The connecting end (400) is formed by locally solidifying the end portion of the light guide main body layer (300) or coating the end portion with a hard material so as to form a rigid or semi-rigid butt joint structure.

4. The flexible laser backlight of claim 3, wherein, The light guide main body layer (300) is provided with a microscale interlocking structure (500) between the bulk scattering particle composite layer (100) and the light guide main body layer (300) and between the light guide main body layer (300) and the reflecting layer (200), the interlocking structure (500) comprises a micron-level convex point array (510) arranged on the surface of the light guide main body layer (300) and a micron-level groove array (520) correspondingly arranged on the attaching surface of the bulk scattering particle composite layer (100) and the reflecting layer (200), and the convex point and the groove are in interference fit.

5. The flexible laser backlight of claim 1, wherein, The application further discloses a manufacturing method of the backlight panel, which comprises the following steps: A mold is provided, and the side leakage optical fiber (311) group (310) is fixed in the mold according to the design; 6. The flexible laser backlight of claim 1, wherein, Unsolidified transparent flexible polymer material is poured into the mold so as to coat the side leakage optical fiber (311) group (310) and solidify, thereby forming the light guide main body layer (300); 7. The flexible laser backlight of claim 1, wherein, The bulk scattering particle composite layer (100) is formed on the light outlet surface side of the light guide main body layer (300); 8. A method for manufacturing a flexible laser backlight according to any one of claims 1 to 7, characterized in that, The reflecting layer (200) is formed on the backlight surface side of the light guide main body layer (300); The end portion of the light guide main body layer (300) is locally hardened or a hard component is additionally arranged to form the connecting end (400), and the light inlet end surface is polished. ​ ​ ​ ​ 9. The production method according to claim 8, characterized by, The body scattering particle composite layer (100) is formed on the light exit surface side of the light guide body layer (300), specifically: An uncured gel mixture containing scattering particles is coated on the light exit surface side of the light guide body layer (300), and then cured; Or, a flexible film containing scattering particles is prepared in advance as an independent film, and then attached to the light exit surface side of the light guide body layer (300) by optical adhesive.

10. The preparation method according to claim 8, characterized in that, One end of the light guide body layer (300) is treated to form the connecting end (400), specifically: The end region is locally heated, ultraviolet irradiated, or chemically treated to cause local hardening; Or, a sleeve or frame made of hard material is complexly coated on the end.

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