Vehicle-mounted backlight without pressing white block

Abstract

This invention discloses a vehicle-mounted backlight that eliminates white clumps, relating to the field of vehicle-mounted display devices. It includes a light guide plate, an LED light source disposed on one side of the light guide plate, and an optical film assembly disposed on the light-emitting surface of the light guide plate. The light guide plate has an incident light surface and an emitting light surface. Its back side has a dot array for converting point light sources into surface light sources. The dot array includes several light-guiding dots arranged in a non-uniform pattern, forming at least one directional channel on the back side of the light guide plate for directing airflow during adsorption, thereby reducing air stagnation in the edge areas. The LED light source is arranged in an array, with its density and position matching the high-density areas in the non-uniform dot layout of the light guide plate. The LED light source is used to inject light into the light guide plate. This vehicle-mounted backlight, through its non-uniform dot layout and airflow channel, combined with a light source matching design, eliminates adsorption white clumps at the source, improving display quality and reliability in vehicle environments.

Description

Technical Field

[0001] This invention relates to automotive display device technology, specifically to an automotive backlight that does not require pressing. Background Technology

[0002] Among various backlight technologies, edge-lit backlighting is widely used in large-size automotive displays due to its thinness and high efficiency. This technology relies on a light guide plate etched with micro- and nano-structures (i.e., "dots") to guide light emitted from a point light source (usually an LED) from the side. Through total internal reflection and scattering by the dots, the light is transformed into a uniform surface light source. However, in the manufacturing process of backlights, to ensure a tight, dust-free, and gap-free fit between the light guide plate and optical films (such as diffusers and brightness enhancement films), the industry generally uses vacuum adsorption for assembly. It is in this critical process that a long-standing pain point in the industry becomes apparent: white spot defects.

[0003] The term "white clump" refers to white spots or blocky areas visible at specific angles when the light guide plate is finally illuminated, caused by the localized trapping of tiny air bubbles or air pockets between the light guide plate and the optical film during or after vacuum adsorption, or by localized stress concentration on the back of the light guide plate due to adsorption pressure. The root cause lies in the fact that traditional light guide plate dot designs often feature uniform or simple gradient distributions. During vacuum adsorption, this layout easily creates air traps at the edges of the light guide plate or in areas with sparse dots, forming negative pressure traps. When the external force is removed, these trapped air bubbles cannot escape smoothly and are compressed between the interfaces, forming visible air bubbles. Furthermore, the localized high pressure generated by the adsorption head is directly transmitted through the rigid dot structure to weak areas on the surface of the light guide plate (such as the edges of the dots), causing excessive instantaneous stress in the material, resulting in whitening and permanent defects.

[0004] White spots severely compromise the purity and uniformity of the image, which is unacceptable for automotive displays that demand the highest quality. To address this issue, the industry has explored various solutions:

[0005] Firstly, the adsorption process can be optimized, such as reducing adsorption pressure, segmented adsorption, and using fixtures with better air permeability. However, these methods often sacrifice production efficiency and cannot fundamentally eliminate the formation of white clumps, which is a temporary solution.

[0006] Secondly, improve the material formulation, such as using a light guide plate material with lower hardness to enhance toughness, but this will sacrifice optical performance and heat resistance, and will be more prone to deformation in the continuous vibration of the vehicle environment.

[0007] Thirdly, improvements can be made to the dot design, such as using a smoother dot shape. While this may alleviate the problem to some extent, it does not systematically solve the issues of airflow and pressure dispersion, and the effect is limited.

[0008] Fourth, some solutions address the structural relationship between the backlight module and surrounding components. For example, patent application CN210270703U discloses an electronic device that uses a clearance space between the housing, support frame, and elastic electrical connector to accommodate the conductive adhesive portion, aiming to solve the white spot problem on the display screen. Another example is patent application CN119355991A, which discloses a display module that solves the white spot problem of the backlight by using a non-overlapping pad structure between the printed circuit board and the backlight module frame. These solutions attempt to avoid white spots by isolating or buffering the hard contact between different components, but they do not provide effective solutions for the fundamental air trapping and stress concentration problems caused by the dot design defects of the light guide plate itself.

[0009] Even more challenging is the stark difference between the automotive environment and the consumer electronics environment. The continuous bumps, vibrations, and temperature and humidity cycles during vehicle operation pose a significant challenge to the long-term reliability of backlights. On one hand, repeated mechanical stress can accelerate the propagation of microcracks or stress concentration points already present under static adsorption, leading to the later manifestation of potential white spot defects. On the other hand, traditional backlight designs do not fully consider structural stability under dynamic mechanical environments and lack effective vibration suppression and energy dissipation mechanisms, resulting in products that are in good working order at the factory but experience frequent reliability issues after a period of user use.

[0010] In summary, there is a lack of existing technologies for automotive backlight solutions that can systematically solve the problem of adsorbed white clumps at the source, while also effectively resisting the complex dynamic environment of vehicles. Summary of the Invention

[0011] The purpose of this invention is to provide a vehicle backlight that does not produce white clumps when pressed, in order to solve the reliability problems of existing technologies where air retention and stress concentration easily occur during vacuum adsorption due to unreasonable dot design of the light guide plate, resulting in white clump defects and inability to adapt to the bumpy and vibrating environment of a vehicle.

[0012] To achieve the above objectives, the present invention provides the following technical solution: a vehicle-mounted backlight that does not require pressing, comprising a light guide plate, an LED light source disposed on one side of the light guide plate, and an optical film assembly disposed on the light-emitting surface of the light guide plate, wherein:

[0013] The light guide plate has a light-incident surface and a light-exit surface. Its back side is provided with a dot array for converting a point light source into a surface light source. The dot array includes several light guide dots arranged in a non-uniform manner, and forms at least one directional channel on the back side of the light guide plate for directing the airflow during adsorption, so as to reduce air stagnation in the edge area. At least some of the dots have a geometric structure for dispersing adsorption pressure. The geometric structure is a stepped structure, a rounded corner structure, or a combination thereof, to avoid local stress concentration.

[0014] The LED light source is arranged in an array, and its arrangement density and position match the high-density area in the non-uniform dot layout of the light guide plate. The LED light source is used to inject light into the light guide plate.

[0015] An optical film assembly is stacked on the light-emitting surface of a light guide plate to enhance and diffuse the emitted light. The optical film assembly includes at least a reflective sheet, a diffuser plate, and a light-enhancing film arranged sequentially from bottom to top.

[0016] Furthermore, the dot array is also provided with anti-slip anchor points. The shape of the anti-slip anchor points in the transverse section is a non-rotationally symmetric polygon or polygonal shape, which is used to suppress the relative micro-slip between the optical film assembly and the light guide plate in the vehicle vibration environment.

[0017] Furthermore, the dots arranged on the dot array are a gradient hardness composite structure, with the hardness gradually decreasing from the bottom connected to the light guide plate to the top in contact with the optical film, forming a rigid core and a flexible contact layer.

[0018] Furthermore, the non-uniform dot pattern layout was determined through vibration modal analysis optimization. The specific process includes: establishing a finite element model that includes a light guide plate, LED light source and optical film group, simulating vibration conditions in the vehicle environment, identifying the natural frequency of the light guide plate and stress concentration areas prone to resonance, and using a denser and / or smaller dot pattern in the stress concentration areas to enhance structural rigidity and suppress resonance.

[0019] Furthermore, the light guide plate is made of composite damping material, or nano-scale damping particles are mixed into the light guide plate body material. The damping particles are used to absorb and dissipate the mechanical energy generated by vibration.

[0020] Furthermore, the edges of the stepped or rounded corner structure of the light guide dots are provided with micron-scale biomimetic irregular textures or wrinkles, which are used to disperse and attenuate vibrational energy at the microscale.

[0021] Furthermore, the directional channels formed by the non-uniform grid layout are not parallel to the main vibration direction in the vehicle environment, so as to avoid the airflow channels being blocked during vibration.

[0022] Furthermore, it also includes at least one micro-strain sensor and a brightness sensor integrated on the light guide plate. The micro-strain sensor is used to monitor the stress or deformation state of the light guide plate under vibration conditions in real time.

[0023] Furthermore, the micro-strain sensor and brightness sensor are connected to an external control module to output a warning signal or activate an optical compensation mechanism when the stress or brightness detected by the sensor exceeds a preset safety threshold.

[0024] Furthermore, the external control module includes a processor and a multi-channel LED driver circuit. The processor is electrically connected to the micro-strain sensor and the driver circuit, and the processor is configured to perform the following steps:

[0025] Read the stress or deformation data collected by the micro-strain sensor and determine whether it exceeds the first preset threshold. If so, send an early warning signal to the external control module.

[0026] Read the brightness data collected by a brightness sensor and determine whether there are areas in the brightness data where the local brightness changes exceed a second preset threshold.

[0027] If present, a current adjustment command for the multi-channel LED driver circuit is generated based on the direction and magnitude of the local brightness change, instructing the LED current in the dimming region to increase and / or decrease the LED current in the brightening region to achieve brightness rebalancing.

[0028] Compared with existing technologies, this invention provides a vehicle-mounted backlight source without pressed white clumps. It combines a light guide plate dot design with a non-uniform layout, and coordinates the structure of the light source and the diaphragm. Simultaneously, it introduces a mechanical optimization and dynamic compensation mechanism tailored to the vehicle environment. The non-uniform dot layout forms directional channels on the back of the light guide plate, and the adsorption pressure is dispersed through the dot edges with specific geometric shapes. This fundamentally blocks the two main pathways leading to white clump defects during vacuum adsorption: air retention and localized stress concentration. Specific technical effects include the following:

[0029] 1. By optimizing the grid layout through vibration modal analysis to enhance structural rigidity, and by using composite damping materials or microstructures to attenuate vibration energy, the long-term structural stability of the backlight is ensured under vehicle bumpy conditions.

[0030] 2. By integrating sensors and dimmable drive circuits, the optical performance fluctuations caused by vibration are dynamically compensated in real time, meeting the high standards of high-end automotive products for backlights in terms of manufacturing yield and long-term service reliability. Especially in complex automotive dynamic environments, it can effectively maintain the uniformity and purity of the displayed image. Attached Figure Description

[0031] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in this invention. For those skilled in the art, other drawings can be obtained based on these drawings.

[0032] Figure 1 This is a schematic diagram illustrating the principle of Embodiment 1 of the present invention;

[0033] Figure 2 This is a schematic diagram of the overall structure of Embodiment 1 of the present invention;

[0034] Figure 3 This is a schematic diagram of the light guide plate and dot array in Embodiment 1 of the present invention;

[0035] Figure 4 This is a schematic diagram of the structure of Embodiment 2 of the present invention;

[0036] Figure 5 This is a schematic diagram of the structure of Embodiment 3 of the present invention.

[0037] Explanation of reference numerals in the attached figures:

[0038] 1. Light guide plate; 2. LED light source; 3. Optical film assembly; 301. Reflective sheet; 302. Diffuser plate; 303. Brightness enhancement film; 4. Anti-slip anchor point; 5. Dot array; 6. External control module. Detailed Implementation

[0039] To enable those skilled in the art to better understand the technical solution of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings.

[0040] As attached Figure 1 To be continued Figure 3 As shown:

[0041] Example 1:

[0042] The present invention provides a vehicle backlight that does not require pressing, including a light guide plate 1, an LED light source 2 disposed on one side of the light guide plate 1, and an optical film group 3 disposed on the light-emitting surface of the light guide plate 1.

[0043] 1. In one embodiment of the present invention, the light guide plate 1 has a light-incident surface and a light-exit surface, and its back side is provided with a dot array 5 for converting a point light source into a surface light source. The dot array 5 includes a plurality of light guide dots arranged in a non-uniform manner, and at least one directional channel (not shown in the figure) is formed on the back side of the light guide plate 1 for directing the airflow during adsorption, so as to reduce air retention in the edge area. At least some of the dots have a geometric structure for dispersing adsorption pressure. The geometric structure is a stepped structure, a rounded corner structure or a combination thereof, to avoid local stress concentration.

[0044] 2. In one embodiment of the present invention, the LED light source 2 is arranged in an array, and its arrangement density and position match the high-density area in the non-uniform dot layout of the light guide plate 1. The LED light source 2 is used to inject light into the light guide plate 1.

[0045] 3. In one embodiment of the present invention, the optical film group 3 is stacked on the light-emitting surface of the light guide plate 1 for brightening and diffusing the emitted light. The optical film group 3 includes at least a reflective sheet 301, a diffuser plate 302 and a brightness enhancement film 303 arranged sequentially from bottom to top.

[0046] 4. In one embodiment of the present invention, the non-uniform dot layout is determined through vibration modal analysis optimization, and the specific process includes the following four steps:

[0047] Step 1: Establish a multiphysics coupling simulation model. First, in the finite element analysis software, establish a detailed 3D model containing a light guide plate 1, an LED light source 2, and an optical film assembly 3. This model needs to define the material properties of each component, including but not limited to: the Young's modulus, Poisson's ratio, and density of the light guide plate 1; the thickness and elastic modulus of each thin film layer in the optical film assembly 3; and simplify the LED light source 2 to a boundary condition bearing a fixed load and a mass point.

[0048] Step Two: Modal Analysis and Resonance Identification. Loads are applied to the established assembly model to simulate the random vibration spectrum or swept-frequency vibration excitation of a vehicle under typical road conditions (such as gravel roads and speed bumps). Through calculation, the natural frequencies, mode shapes, and stress distribution cloud maps of the light guide plate 1 at lower orders (such as first and second order) are extracted. Based on these data, the frequency range in which the light guide plate 1 is most prone to resonance is identified, and the physical region where maximum stress (i.e., stress concentration) occurs during vibration is precisely located.

[0049] Step 3: Parametric Layout of Dots Based on Stress Results. The coordinates of the identified stress concentration areas are imported into the dot layout algorithm. Within these areas, smaller dot diameters and / or higher dot densities (more dots per unit area) are used for arrangement. The principle is that smaller dot sizes reduce the stiffness of individual dots, while higher density is equivalent to adding reinforcing ribs to the structure. Together, these factors increase the local structural rigidity of the weak area, altering its local dynamic response characteristics and thus avoiding overlap with the overall resonant frequency.

[0050] Step 4: Iterative Verification and Layout Finalization. The new dot layout optimized in Step 3 is re-introduced into the finite element model for modal analysis. The simulation results before and after optimization are compared to verify whether the stress peak value has been significantly reduced and whether the resonance risk has been effectively avoided. If the expected results are not achieved, the process returns to Step 3 to adjust the dot parameters (e.g., further reducing the size or increasing the density) until simulation results show that the dynamic mechanical properties of the light guide plate 1 meet the design requirements, thus finalizing the non-uniform dot layout scheme.

[0051] 5. In one embodiment of the present invention, the light guide plate 1 is made of a composite damping material, or nano-scale damping particles are mixed into the body material of the light guide plate 1. The damping particles are used to absorb and dissipate the mechanical energy generated by vibration.

[0052] 6. In one embodiment of the present invention, the directional channel formed by the non-uniform dot layout is not parallel to the main vibration direction in the vehicle environment, so as to avoid the airflow channel being blocked during vibration.

[0053] Working Principle: In the above embodiment one, the backlight, through the comprehensive design, utilizes a directional airflow channel formed by the non-uniform layout of the dots during the manufacturing stage to ensure rapid and orderly air expulsion during vacuum adsorption, preventing the formation of white clumps at the source. During the usage stage, the vibration-optimized dot layout, damping materials, and anti-clogging channel design work together to resist the influence of the vehicle vibration environment, maintain structural stability, and prevent new optical defects induced by vibration. The matching layout of the LED light source 2 further ensures the basic optical performance.

[0054] As attached Figure 4 As shown:

[0055] Example 2:

[0056] This embodiment is basically the same as the previous embodiment, except that the dot array 5 is also provided with anti-slip anchor points 4. The shape of the anti-slip anchor points 4 in the transverse cross section is a non-rotationally symmetric polygon or polygonal shape, which is used to suppress the relative micro-slip between the optical film group 3 and the light guide plate 1 in the vehicle vibration environment.

[0057] 1. In one embodiment of the present invention, each dot arranged on the dot array 5 is a gradient hardness composite structure, which gradually decreases in hardness from the bottom connected to the light guide plate 1 to the top contacting the optical film, forming a rigid core and a flexible contact layer.

[0058] 2. In one embodiment of the present invention, the edges of the stepped or rounded corner structure of the light guide dots are provided with micron-level biomimetic irregular textures or wrinkles, which are used to disperse and attenuate vibration energy at the microscale.

[0059] Working Principle: Example 2, building upon Example 1, adds three additional structures to address the impact of vibrations at different scales. The anti-slip anchor point 4, through its asymmetrical shape, increases friction, directly limiting the relative slippage between the optical film and the light guide plate 1. The gradient hardness structure makes the top of the dots softer, deforming under pressure to buffer impacts. The microtexture forms an irregular surface at the edges of the dots, causing vibration energy to dissipate through scattering during propagation. These three structures function by limiting displacement, buffering impacts, and dissipating energy, respectively, working together to eliminate frictional damage and optical performance degradation that may be caused by vibration, thus improving the long-term reliability of the backlight.

[0060] As attached Figure 5 As shown:

[0061] Example 3:

[0062] This embodiment is basically the same as the previous embodiment, except that the vehicle backlight also includes at least one micro-strain sensor and a brightness sensor integrated on the light guide plate 1. The micro-strain sensor is used to monitor the stress or deformation state of the light guide plate 1 under vibration conditions in real time, and the brightness sensor is used to monitor the optical performance.

[0063] 1. In one embodiment of the present invention, the micro-strain sensor, the brightness sensor and an external control module 6 are communicatively connected, and are used to output a warning signal or activate an optical compensation mechanism when the stress or brightness detected by the sensor exceeds a preset safety threshold.

[0064] 2. In one embodiment of the present invention, the external control module 6 includes a processor and a multi-channel LED driving circuit. The processor is electrically connected to the micro-strain sensor and the driving circuit, and the processor is configured to perform the following steps:

[0065] Read the stress or deformation data collected by the micro-strain sensor and determine whether it exceeds the first preset threshold. If so, send a warning signal to the external control module 6.

[0066] Read the brightness data collected by a brightness sensor and determine whether there are areas in the brightness data where the local brightness changes exceed a second preset threshold.

[0067] If present, a current adjustment command for the multi-channel LED driver circuit is generated based on the direction and magnitude of the local brightness change, instructing the LED current in the dimming region to increase and / or decrease the LED current in the brightening region to achieve brightness rebalancing.

[0068] Working principle: Based on Example 2, Example 3 uses sensors to acquire stress or deformation data of the light guide plate 1 in real time. The processor compares this data with a first preset threshold. If the data exceeds the threshold, an early warning is issued, indicating that the structure is approaching its load-bearing limit. At the same time, the processor reads the brightness sensor data to determine whether there are local brightness changes that exceed a second preset threshold. If so, the processor analyzes the direction and magnitude of the change and generates a current adjustment command, which is sent to the multi-channel LED driver circuit. The driver circuit increases the LED current in the brightness-decreased area or decreases the LED current in the brightness-enhanced area accordingly, so that the screen brightness distribution is restored to uniformity. Through real-time monitoring and local dimming, the system actively corrects optical unevenness caused by vibration, avoids display defects, and improves the display stability and reliability of the backlight in the vehicle environment.

[0069] The foregoing has only described certain exemplary embodiments of the present invention by way of illustration. Undoubtedly, those skilled in the art can modify the described embodiments in various ways without departing from the spirit and scope of the present invention. Therefore, the foregoing drawings and descriptions are illustrative in nature and should not be construed as limiting the scope of protection of the claims of the present invention.

Claims

1. A vehicle-mounted backlight that does not require pressing, comprising a light guide plate (1), an LED light source (2) disposed on one side of the light guide plate (1), and an optical film assembly (3) disposed on the light-emitting surface of the light guide plate (1), characterized in that: The light guide plate (1) has a light-incident surface and a light-outceasing surface. Its back side is provided with a dot array (5) for converting a point light source into a surface light source. The dot array (5) includes a number of light guide dots arranged in a non-uniform manner and forms at least one directional channel on the back side of the light guide plate (1) for directing the airflow during adsorption. At least some of the dots have a geometric structure for dispersing adsorption pressure. The geometric structure is a stepped structure, a rounded corner structure, or a combination thereof. The LED light source (2) is arranged in an array, and its arrangement density and position match the high-density area in the non-uniform dot layout of the light guide plate (1). The LED light source (2) is used to inject light into the light guide plate (1). The optical film assembly (3) is stacked on the light-emitting surface of the light guide plate (1) and is used to brighten and diffuse the emitted light. The optical film assembly (3) includes at least a reflective sheet (301), a diffuser plate (302) and a brightness enhancement film (303) arranged sequentially from bottom to top.

2. The vehicle-mounted backlight without pressed white blob as described in claim 1, characterized in that, The dot array (5) is also provided with anti-slip anchor points (4), and the shape of the anti-slip anchor points (4) in the transverse section is a non-rotationally symmetric polygon or polygonal shape.

3. The vehicle-mounted backlight without pressed white blob as described in claim 1, characterized in that, The dots arranged on the dot array (5) are a gradient hardness composite structure. The hardness gradually decreases from the bottom connected to the light guide plate (1) to the top in contact with the optical film, forming a rigid core and a flexible contact layer.

4. The vehicle-mounted backlight without pressed white blob as described in claim 1, characterized in that, The non-uniform dot layout was determined through vibration modal analysis optimization. The specific process includes: establishing a finite element model containing a light guide plate (1), an LED light source (2), and an optical film group (3) to simulate the vibration conditions under vehicle environment, identifying the natural frequency of the light guide plate (1) and the stress concentration area that is prone to resonance, and using a denser and / or smaller dot arrangement in the stress concentration area to enhance structural rigidity and suppress resonance.

5. A vehicle-mounted backlight without pressed white blob as described in claim 1, characterized in that, The light guide plate (1) is made of composite damping material.

6. A vehicle-mounted backlight without pressed white blob as described in claim 1, characterized in that, The edges of the stepped or rounded corner structure of the light guide dots have micron-level biomimetic irregular textures or folds.

7. A vehicle-mounted backlight without pressed white blob as described in claim 1, characterized in that, The directional channel formed by the non-uniform grid layout is not parallel to the main vibration direction in the vehicle environment.

8. A vehicle-mounted backlight without pressed white patches according to claim 1, characterized in that, It also includes at least one micro-strain sensor and a brightness sensor integrated on the light guide plate (1). The micro-strain sensor is used to monitor the stress or deformation state of the light guide plate (1) under vibration conditions in real time.

9. A vehicle-mounted backlight without pressing white patches according to claim 8, characterized in that, The micro-strain sensor and brightness sensor are connected to an external control module (6) for outputting a warning signal or activating an optical compensation mechanism when the stress or brightness detected by the micro-strain sensor exceeds a preset safety threshold.

10. A vehicle-mounted backlight without pressed white patches according to claim 9, characterized in that, The external control module (6) includes a processor and a multi-channel LED driving circuit. The processor is electrically connected to the micro-strain sensor and the driving circuit. The processor is configured to perform the following steps: a: Read the stress or deformation data collected by the micro-strain sensor and determine whether it exceeds the first preset threshold. If so, send an early warning signal to the external control module (6). b: Read the brightness data collected by a brightness sensor and determine whether there are areas in the brightness data where the local brightness changes exceed the second preset threshold; c: If present, a current adjustment command for the multi-channel LED driver circuit is generated based on the direction and magnitude of the local brightness change, instructing to increase the LED current in the brightness-decreased region and / or decrease the LED current in the brightness-enhancing region to achieve brightness rebalancing.

Images