Bilateral surface scattering high-uniform light guide plate, processing method and backlight plate

Abstract

This invention relates to a double-sided, highly uniform light guide plate with side scattering, a processing method, and a backlight plate. The light guide plate includes a first end, a second end, a center position, a first side, a second side, a first scattering structure, and a second scattering structure. The first scattering structure is disposed on the first side and includes multiple scattering holes. The aperture, depth, and density of the scattering holes gradually increase in the direction from the first end toward the center position and from the second end toward the center position. The maximum thickness of the light guide plate is denoted as D, the maximum depth of the scattering holes is denoted as H1, and the minimum depth of the scattering holes is denoted as H2. H1 and H2 are both within the range of [1 / 10D, 1 / 4D]. The aperture change, depth change, and spacing change of adjacent scattering holes are K1, K2, and K3, respectively, wherein the values ​​of K1, K2, and K3 decrease sequentially. The second side has a first inclined surface to gradually reduce the thickness of the light guide plate. By combining the scattering holes and the first inclined surface, total internal reflection is disrupted, resulting in a more uniform light output from the light guide plate.

Description

Technical Field

[0001] This invention relates to the technical field of television backlight panels, and more particularly to a double-sided side-scattering high-uniformity light guide plate, its processing method, and the backlight panel. Background Technology

[0002] Large-size, high-brightness, narrow-bezel or borderless LCD displays have become the current market trend. LCD displays include backlight modules, which typically employ an edge-lit LED strip structure. The light guide plate, as a crucial component of the edge-lit backlight system, influences the optical properties of the backlight source, further affecting the display's image quality. Research on high-performance light guide plates is an important aspect of overall backlight development.

[0003] In existing technologies, light guide plates in televisions typically feature multiple dots to improve their uniformity and thus enhance the display's picture quality. For example, patent document CN110879436A discloses a light guide plate structure and dot arrangement method. The light guide plate structure includes a light guide plate, a light strip located on the lower side of the light guide plate, an upper reflective film located on the upper side of the light guide plate, a left reflective film located on the left side of the light guide plate, and a right reflective film located on the right side of the light guide plate. The light guide plate is divided into a lower light-incident side and an upper light-exit side. The light guide plate has several dots of equal size, arranged randomly along the X-axis and regularly along the Y-axis. The dots are elliptical in shape, with their major axis parallel to the X-axis. The random dot arrangement of the light guide plate dots solves the problems of interference patterns and visible dot defects caused by regular dot arrangements. However, this technical solution relies solely on setting dots with increasing aperture from the light-incident side to the light-outcident side. While this method can improve the uniformity of the light guide plate to some extent, it is clearly insufficient for televisions that require high-definition display. Furthermore, existing light guide plates typically use laser engraving equipment to create the dots, which is inefficient. Summary of the Invention

[0004] The first objective of this invention is to provide a double-sided scattering light guide plate with high uniformity, which aims to solve the technical problem of insufficient light output uniformity of existing light guide plates.

[0005] To solve the above technical problems, a double-sided scattering high uniformity light guide plate is provided, including a first end, a second end, a center position, a first side, and a second side; A first scattering structure is disposed on the first side. The first scattering structure includes a plurality of scattering holes evenly distributed in multiple rows. The aperture, depth, and density of the scattering holes gradually increase in the direction from the first end toward the center position and from the second end toward the center position. The maximum thickness of the light guide plate is denoted as D, the maximum depth of the scattering holes is denoted as H1, and the minimum depth of the scattering holes is denoted as H2. H1 and H2 are both within the range of [1 / 10D, 1 / 4D]. The aperture change, depth change, and spacing change of two adjacent scattering holes are K1, K2, and K3, respectively, wherein the values ​​of K1, K2, and K3 decrease sequentially. The second scattering structure is disposed on the second side, and the second side is provided with a first inclined surface so that the thickness of the light guide plate gradually decreases in the direction from the first end toward the center position and from the second end toward the center position.

[0006] Further, let the density of the scattering apertures be denoted as M, then ; in, This represents the radius of the scattering aperture. This represents the horizontal distance between the centers of two adjacent scattering apertures in the same row. This represents the vertical distance between the centers of two adjacent rows of scattering apertures, and and All are variables.

[0007] Furthermore, the scattering aperture includes a first aperture segment, a second aperture segment, and a third aperture segment, which are connected sequentially. In the direction from the first aperture segment to the third aperture segment, the aperture of the second aperture segment extends with a gradually decreasing trend, and the aperture of the third aperture segment extends with a gradually increasing trend.

[0008] Furthermore, the light guide plate also includes a plurality of protrusions extending from the second aperture segment, the plurality of protrusions being circumferentially spaced around the axis of the second aperture segment.

[0009] Furthermore, the inner surface of the third hole segment has a micro-nano frosted texture; and the taper of the third hole segment is configured to be 1.2-1.5 times the taper of the second hole segment.

[0010] Furthermore, the second scattering structure includes a plurality of extended strips arranged in an array.

[0011] Furthermore, the end of the extension strip opposite to the first side has an arc-shaped end face, and adjacent sides of the arc-shaped end face on the extension strip have inclined end faces. The inclination angle of the inclined end faces gradually increases in the direction from the first end toward the center position and from the second end toward the center position.

[0012] Furthermore, a microlens array is formed on the arc-shaped end face, and the microlens array is configured as a micron-scale hemispherical structure that protrudes from the arc-shaped end face and is distributed in an array.

[0013] A second objective of this invention is to provide a method for processing a light guide plate, for preparing the aforementioned light guide plate, the method comprising: S1. The light guide plate substrate is formed by injection molding and the first scattering structure is formed integrally. S2. Using a first-power laser, the basic outline of the extension strip is engraved on the second side of the light guide plate substrate, so that the extension strip forms an arc end face and an inclined end face; S3. A microlens array is engraved on the arc-shaped end face of the extension strip using a second power laser to complete the processing of the second scattering structure and obtain the finished light guide plate; wherein, the first power is greater than the second power.

[0014] A third objective of the present invention is to provide a backlight panel, comprising a housing, LED strips, a diffusion film, a reflective film, and the aforementioned light guide plate. The housing has an installation cavity formed therein, and the LED strips, the diffusion film, the reflective film, and the light guide plate are all disposed within the installation cavity. The reflective film is disposed on the first side of the light guide plate, the diffusion film is disposed on the second side of the light guide plate, and the two LED strips are respectively disposed at the first end and the second end of the light guide plate.

[0015] Implementing the embodiments of the present invention will have the following beneficial effects: In one embodiment, the first scattering structure on the first side of the light guide plate adopts a scattering hole design with the aperture, depth, and density gradually increasing from the light incident end to the center. Combined with the second scattering structure on the second side with a first inclined surface, it works together to destroy total internal reflection of light from both sides, avoiding the problem of uneven light output caused by the single scattering structure in the prior art. This significantly improves the overall light output uniformity of the light guide plate and can meet the optical requirements of high-definition display of large-size TVs.

[0016] In another embodiment, by setting a first aperture segment, a second aperture segment, and a third aperture segment, light undergoes multiple refractions and diffuse reflections within the scattering aperture, further disrupting the directional total internal reflection of light, while avoiding stray light reflection and improving the purity of the emitted light.

[0017] In another embodiment, the extension strip of the second scattering structure is provided with an arc-shaped end face and two inclined end faces on both sides, and the inclination angle of the inclined end face gradually increases from the light-incident end to the center position, which is adapted to the gradual thickness characteristics of the light guide plate, so that the light is smoothly refracted along the inclined surface; the micron-level hemispherical microlens array protruding on the arc-shaped end face collimates and refracts the diffuse reflection light, effectively improving the output brightness while ensuring the uniformity of light output, and at the same time expanding the light output angle and improving the visual experience of the display screen.

[0018] In another embodiment, the light guide plate substrate and the complex first scattering structure are integrally molded using injection molding, replacing the inefficient method of laser point-by-point engraving of complex structures; then, the relatively simple second scattering structure is processed by laser layer engraving. High-power laser rapidly forms the outline of the extension strip, while low-power laser finely processes the microlens array. This ensures both the forming efficiency of the overall structure of the extension strip and the micron-level processing accuracy of the microlens array, avoiding optical effect attenuation due to insufficient processing accuracy and ensuring the consistency of the optical performance of the finished light guide plate. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0020] Figure 1 This is a front view of the light guide plate described in Embodiment 1 of the present invention; Figure 2 for Figure 1 A magnified view of a portion of point B in the middle; Figure 3 for Figure 1 A cross-sectional view along the CC line; Figure 4 for Figure 3 A magnified view of a portion of point D in the middle; Figure 5 This is a flowchart of the processing method of the light guide plate according to Embodiment 1 of the present invention; Figure 6 This is a cross-sectional view of the backlight panel described in Embodiment 2 of the present invention; Figure 7 This is a bottom view of the light guide plate described in Embodiment 2 of the present invention.

[0021] Wherein: 100, light guide plate; 110, first end; 120, second end; 130, center position; 140, first side; 150, second side; 160, first scattering structure; 161, scattering hole; 1611, first hole segment; 1612, second hole segment; 1613, third hole segment; 1614, micro / nano frosted texture; 162, bump; 170, second scattering structure; 171, extension strip; 1711, arc-shaped end face; 1712, inclined end face; 1713, microlens array; 180, first inclined surface; 200. Backlight panel; 210. Housing; 211. Mounting cavity; 220. Lamp strip; 230. Diffuser film; 240. Reflective film. Detailed Implementation

[0022] To facilitate understanding of the present invention, a more complete description will be given below with reference to the accompanying drawings. Preferred embodiments of the invention are shown in the drawings. However, the invention can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to provide a thorough and complete understanding of the disclosure of the invention.

[0023] It should be noted that when a component is said to be "fixed to" another component, it can be directly attached to the other component or there may be an intervening component. When a component is said to be "connected to" another component, it can be directly connected to the other component or there may be an intervening component. The terms "vertical," "horizontal," "left," "right," and similar expressions used in this document are for illustrative purposes only.

[0024] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0025] Example 1: Please refer to Figures 1-4This invention provides a light guide plate 100, including a first end 110, a second end 120, a center position 130, a first side 140 and a second side 150, a first scattering structure 160 and a second scattering structure 170. The first scattering structure 160 is disposed on the first side 140 and includes a plurality of scattering holes 161 evenly distributed in multiple rows. In the directions from the first end 110 toward the center position 130 and from the second end 120 toward the center position 130, the aperture, depth and density of the scattering holes 161 gradually increase. The maximum thickness of the light guide plate 100 is denoted as D, the maximum depth of the scattering holes 161 is denoted as H1, and the minimum depth of the scattering holes 161 is denoted as H2. H1 and H2 are both within the range of [1 / 10D, 1 / 4D]. The aperture change, depth change and spacing change of two adjacent scattering holes 161 are K1, K2 and K3, respectively, wherein the values ​​of K1, K2 and K3 decrease sequentially. The second scattering structure 170 is disposed on the second side 150. The second side 150 of the second scattering structure 170 has a first inclined surface 180, so that the thickness of the light guide plate 100 gradually decreases in the direction from the first end 110 toward the center position 130 and from the second end 120 toward the center position 130. Exemplarily, the light guide plate 100 of this application is configured to receive light from both sides, from the first end 110 and the second end 120 respectively, while the center position 130 is located in the middle of the first end 110 and the second end 120. Most of the incident light entering the light guide plate 100 propagates forward in the form of total internal reflection, with no light refracted from the upper surface. To allow the light to refract from the upper surface of the light guide plate 100, scattering dots are usually arranged on the bottom surface of the light guide plate 100 to disrupt total internal reflection, thereby achieving uniform light output. A general design principle is that the scattering dots near the light source should be smaller and sparser, while the scattering dots further away from the light source should be larger and denser. Based on the above basic theoretical design, the light guide plate 100 of this application is designed with a dot distribution scheme. The light guide plate 100 of this application is provided with scattering structures on both the first side 140 and the second side 150. By distributing the aperture, depth and density of the scattering holes 161, the light guide plate 100 achieves better light emission uniformity. In this embodiment, the value of K1 is 0.1 mm, the value of K2 is 0.05 mm, and the value of K3 is -0.05 mm. The tilt angle γ of the first tilted surface 180 is set to 5°-15°. In this embodiment, the tilt angle γ of the first tilted surface 180 is set to 8°. The core function of the first tilted surface 180 is to guide the light emission in conjunction with the second scattering structure 170. If the angle γ < 5°, the tilted surface is close to a plane and cannot effectively change the direction of light propagation. This will cause the light to form directional reflection on the surface of the second side 150, which will not only fail to form a coordinated light uniformity with the first scattering structure 160, but may also cause light to escape from the edge area.If the angle γ > 15°, the refraction effect of the inclined surface will be too strong, causing the light in the central area of ​​the light guide plate 100 to be excessively deflected to the edge, resulting in the opposite effect of dark center and bright edge.

[0026] Please refer to Figure 1 , Figure 2 In one possible implementation, the density of the scattering aperture 161 is denoted as M, then ; in, This indicates the radius of the scattering aperture 161. This represents the horizontal distance between the centers of two adjacent scattering apertures 161 in the same row. This represents the vertical distance between the centers of two adjacent rows of scattering apertures 161, and and All are variables. For example, the spacing between two adjacent rows of scattering holes 161 in the directions of the first end 110 toward the center position 130 and the second end 120 toward the center position 130. The diameter of the scattering aperture 161 in this application uniformly refers to the maximum nominal diameter of the first aperture segment 1611, and the radius R of the scattering aperture 161 is half of the maximum nominal diameter of the first aperture segment 1611. In this embodiment, the density M of the scattering aperture 161 is set to 0.36. It should be noted that the density M of the scattering aperture 161 can be set according to actual conditions. For example, the density of the scattering aperture 161 of the large-size light guide plate 100 can be set to a range greater than or equal to 0.36 and less than 0.5, and the density of the scattering aperture 161 of the small-size light guide plate 100 can be set to a range greater than or equal to 0.25 and less than 0.36. The formula for the density of the scattering aperture 161 is essentially the area of ​​a single aperture / the grid area occupied by a single aperture, directly reflecting the ability of the scattering aperture 161 to destroy light within a unit area. The higher the area ratio, the stronger the destruction of total internal reflection and the greater the amount of light emitted; conversely, the lower the area ratio, the smaller the light emitted. The formula allows for precise design, calculation, and control of the scattering intensity at different locations, avoiding density chaos caused by empirical arrangement. The root cause of uneven brightness in the light guide plate 100 is excessively high light intensity at the edges and insufficient light intensity at the center, resulting in a mismatch between light scattering intensity and light density. This invention achieves precise matching of light intensity and scattering intensity through a density formula, fundamentally eliminating the brightness difference. This invention quantifies the density of the scattering apertures 161 using the aforementioned formula. The core objective is to precisely match the light distribution pattern within the light guide plate 100: the edge region has high light density and concentrated energy, so a low density is set to reduce scattering and suppress excessive edge brightness; the center region has low light density and insufficient energy, so a high density is set to enhance scattering and compensate for the central dark area. Simultaneously, the formula is unified based on the radius of the first aperture segment 1611, eliminating parameter ambiguities caused by differences in the diameters of the three aperture segments. Combined with the gradual change rule of K1>K2>K3 for adjacent scattering apertures 161, it ensures a smooth transition in aperture diameter, depth, and spacing, avoiding sudden density changes that cause bright and dark stripes or interference patterns. This achieves dynamic matching of scattering intensity and light density across the entire area, fundamentally solving the problem of uneven brightness. In this embodiment, the density M of the scattering aperture 161 is set to 0.36. This value is sufficiently reasonable. From an optical perspective, M=0.36 falls within the medium density range, ensuring sufficient scattering intensity in the central area, effectively enhancing central brightness and eliminating dark areas, without causing excessive brightness in the center due to excessive density. It also avoids light leakage or insufficient brightness at the edges due to low density. From a process adaptability perspective, M=0.36 corresponds to a reasonable ratio of the size and spacing of the scattering aperture 161, adapting to the processing precision of the injection mold. This ensures that the scattering aperture 161 is formed completely without missing materials or deformation, balancing processing yield and structural stability. From a global uniformity perspective, this density value can precisely coordinate with the gradient parameters of aperture diameter, depth, and spacing, thereby helping to control the global brightness difference of the light guide plate 100, meeting the optical requirements of high-definition displays, while avoiding problems such as increased light loss and reduced overall brightness due to excessive density, or insufficient scattering and poor uniformity due to excessively low density.

[0027] Please refer to Figure 3 , Figure 4 In one possible implementation, the scattering aperture 161 includes a first aperture segment 1611, a second aperture segment 1612, and a third aperture segment 1613, which are sequentially connected. In the direction from the first aperture segment 1611 to the third aperture segment 1613, the aperture diameter of the second aperture segment 1612 extends in a gradually decreasing trend, and the aperture diameter of the third aperture segment 1613 extends in a gradually increasing trend. Exemplarily, the first aperture segment 1611 is a cylindrical structure, the second aperture segment 1612 is a frustum-shaped structure, and the third aperture segment 1613 is an inverted frustum-shaped structure. The first aperture segment 1611 serves to stabilize the light guide. In the initial stage, light enters the first aperture segment 1611 from the first side 140 of the light guide plate 100. Because the first aperture segment 1611 is a cylindrical structure with a constant aperture, it can initially constrain the incident light, allowing the light to propagate stably along the channel axis and preventing excessive diffuse reflection at the aperture opening, which would lead to local overbrightness. The second aperture segment 1612 serves to directional convergence and angle filtering. The inner wall of the channel gradually converges and constrains the light. Specifically, the light collides with the aperture wall multiple times within the constricting channel, and the incident angle is gradually adjusted to a range closer to the critical angle of total internal reflection, allowing more light to be confined within the channel to continue propagating. At the same time, the constricting channel can filter out stray light incident at large angles, preventing such light from escaping directly from the channel sidewall and causing excessive light output in the edge area, thus retaining more controllable light in the central area. The third aperture segment 1613 serves to achieve multi-directional diffuse reflection and uniform emission. As light enters the gradually increasing aperture segment 1613, the inner wall of the channel creates a gradually expanding diverging effect on the light. Within the expanding channel, the light undergoes multiple reflections and refractions against the channel wall, dispersing its propagation direction into a multi-directional distribution, preventing directional emission in a single direction and forming a uniform diffuse reflection light field. The taper of the third aperture segment 1613 is greater than that of the second aperture segment 1612, further amplifying the divergence angle of the light, allowing the diffuse reflection light to cover a wider angle range, while guiding more light to the central area of ​​the light guide plate 100, compensating for insufficient light at the center position 130. The end of the expanding channel smoothly connects to the inner bottom wall of the light guide plate 100, preventing specular reflection at the bottom of the channel, reducing light loss, and improving light utilization. Through constant constraint, contraction and convergence, and expansion and divergence, the three aperture segments allow the light to undergo multiple angle adjustments and diffuse reflections within the scattering aperture 161, resulting in a more uniform angular distribution of the emitted light. In addition, the multi-level channel structure can disrupt the directional total internal reflection of light, allowing more light to emerge from the second side 150 of the light guide plate 100, while suppressing glare and improving the visual comfort of the displayed image.

[0028] Please refer to Figure 3 , Figure 4In one possible implementation, the light guide plate 100 further includes a plurality of protrusions 162 extending from the second aperture segment 1612, the plurality of protrusions 162 being distributed circumferentially around the axis of the second aperture segment 1612. Exemplarily, four protrusions 162 are also provided within the second aperture segment 1612, the four protrusions 162 being distributed circumferentially at equal intervals around the axis of the second aperture segment 1612, forming a ring array structure. In a preferred embodiment, the protrusions 162 are elongated strip-shaped protrusions extending axially along the second aperture segment 1612, their height being linearly increasing gradient along the direction from the first aperture segment 1611 towards the third aperture segment 1613: the protrusions 162 near the first aperture segment 1611 are smaller in height, and the protrusions 162 near the third aperture segment 1613 are larger in height, with a height variation range of 0.05-0.2 mm; the surface of the protrusions 162 may further be provided with a micro / nano frosted texture 1614 or a microprism texture to enhance the diffuse reflection effect. When light enters the second aperture section 1612 from the first aperture section 1611, where the aperture gradually narrows, the light, which originally propagated along the axial direction of the channel, will collide and reflect multiple times with the circumferentially distributed protrusions 162. As localized protrusions, the protrusions 162 disrupt the smooth continuity of the channel's inner wall, causing the originally directional light to be deflected, preventing the light from directly impacting the third aperture section 1613 along a single axis and preventing excessive light concentration in the central area. The circumferentially spaced protrusions 162 ensure that the light is uniformly dispersed in the circumferential direction, preventing excessive deflection of light in one direction and the formation of localized bright spots. The protrusions 162 employ a gradient height design, perfectly matching the narrowing characteristic of the second aperture section 1612. The lower-height protrusions 162 near the first aperture section 1611 only slightly deflect the incident light, preventing excessive reflection of the incident light at the aperture opening and resulting in overly bright edge areas. The high-height protrusion 162 near the third aperture segment 1613 can more strongly deflect and disperse light, directing more light to the central area of ​​the light guide plate 100, compensating for insufficient light at the center 130. This progressive height gradient design achieves a gentle edge control and enhanced dispersion optical distribution at the center, further reducing the brightness difference between the edge and center of the light guide plate 100. The protrusion 162 structure and the three-stage aperture segment work together to improve light uniformity. The converging channel of the second aperture segment 1612 converges and constrains the light, while the protrusion 162 disperses the light circumferentially based on this constraint. Together, they enable the light to undergo the first homogenization process within the second aperture segment 1612. The light dispersed by the protrusion 162 enters the expanding channel of the third aperture segment 1613, where it undergoes further multi-directional diffuse reflection, completing the second homogenization process. The superposition of two homogenization processes makes the angle distribution of the final emitted light more uniform, effectively avoiding the problem of bright edges, dark centers or uneven brightness in some areas caused by a single scattering hole 161 structure, and controlling the overall brightness difference of the light guide plate 100 to within 5%.

[0029] Please refer to Figure 3, Figure 4 In one possible implementation, the inner surface of the third hole segment 1613 has a micro-nano frosted texture 1614; and the taper of the third hole segment 1613 is configured to be 1.2-1.5 times the taper of the second hole segment 1612. Exemplarily, the inner surface of the third hole segment 1613 is covered with a uniformly distributed micro-nano frosted texture 1614, which is a random or periodic uneven structure with a depth of 0.01-0.03 μm, and can be integrally formed with the third hole segment 1613 by injection molding or laser engraving. The tiny uneven structure of the textured surface causes irregular diffuse reflection of light, breaking the directional specular reflection of light on the smooth hole wall, avoiding concentrated light emission in a single direction, and eliminating local bright spots or dark areas. Regarding the taper ratio, the taper of the third hole segment 1613 is strictly configured to be 1.2-1.5 times the taper of the second hole segment 1612. The hole segment taper is defined as the ratio of the difference in hole diameter at both ends of the hole segment to the axial length of the hole segment, i.e.: ; Please refer to Figure 3 , Figure 4 If the taper of the third aperture segment 1613 is less than 1.2 times the taper of the second aperture segment 1612, the expansion amplitude will be insufficient, the light will not be sufficiently diffused, and the central area will still tend to be too bright. If the taper of the third aperture segment 1613 is greater than 1.5 times the taper of the second aperture segment 1612, the expansion amplitude will be too large, the light will be excessively diffused, and the edge area will tend to be too dark. Limiting it to the 1.2-1.5 times range can accurately balance the light supply between the center and the edge, and control the overall brightness difference of the light guide plate 100. The micro-nano frosted texture 1614 and the taper ratio work together to avoid the light distribution imbalance caused by a single taper structure, and to compensate for the lack of diffuse reflection from smooth aperture walls, so that the light uniformity, brightness consistency and visual comfort of the light guide plate 100 are comprehensively improved.

[0030] Please refer to Figure 3 , Figure 4 In one possible implementation, the second scattering structure 170 includes a plurality of arrayed extension strips 171. Exemplarily, the plurality of extension strips 171 are arrayed to form a continuous mesh optical skeleton on the second side 150 of the light guide plate 100. Its core function is to constrain and distribute light emitted from inside the light guide plate 100 over the entire area. The mesh structure divides the second side 150 of the light guide plate 100 into numerous tiny light-emitting units, each unit corresponding to the enclosed area of ​​a set of longitudinal and transverse extension strips 171, preventing excessive concentration or escape of light in local areas. The uniformity of the array arrangement ensures consistent optical characteristics for each light-emitting unit, laying the foundation for global light emission uniformity and avoiding local brightness differences caused by a single structure.

[0031] Please refer to Figure 3 , Figure 4In one possible implementation, the end of the extension strip 171 facing away from the first side 140 has an arc-shaped end face 1711, and adjacent sides of the arc-shaped end face 1711 on the extension strip 171 have inclined end faces 1712. The inclination angle of the inclined end faces 1712 gradually increases in the directions from the first end 110 toward the center position 130 and from the second end 120 toward the center position 130. For example, the width of the extension strip 171 gradually increases in the directions from the first end 110 toward the center position 130 and from the second end 120 toward the center position 130. The edge region light guide plate 100 has a relatively large thickness, the extension strip 171 has a relatively narrow width, and the angle of the inclined end faces 1712 is relatively small, set between 5° and 8°. This results in a weaker constraint on light, allowing a suitable amount of light to escape and preventing the edge region from being too bright. The central area light guide plate 100 has a smaller thickness, a wider extension strip 171, and a larger angle for the inclined end face 1712, set between 10° and 15°. This enhances the constraint and refraction of light, guiding more light to the central area and compensating for insufficient light at the center position 130. The gradual design of weak constraint at the edges and strong constraint at the center precisely balances the light output of different areas of the light guide plate 100, effectively reducing the brightness difference between the edges and the center. The arc-shaped end face 1711 and surface microstructure of the extension strip 171 perform secondary diffuse reflection and angle optimization of light. The arc-shaped end face 1711 breaks the directional reflection of the planar end face, causing multiple diffuse reflections of light before emission, further dispersing the direction of light propagation and avoiding local bright spots. The inclined end face 1712 guides light to deflect towards the center of the light guide plate 100, strengthening the light supply to the central area while suppressing light overflow from the edge areas.

[0032] Please refer to Figure 3 , Figure 4In one possible implementation, a microlens array 1713 is formed on the arc-shaped end face 1711. The microlens array 1713 is configured as a micron-scale hemispherical structure protruding from the arc-shaped end face 1711 and distributed in an array. Exemplarily, multiple hemispherical microlenses are arranged in a regular, closely spaced array along the extension direction of the extension strip 171, covering the entire effective optical area of ​​the arc-shaped end face 1711. In a specific implementation, the microlenses are standard hemispherical plano-convex microstructures, with a diameter of 100-300 μm and a convex height of 25-75 μm. They are raised structures on the surface of the arc-shaped end face 1711 and are integrally formed with the extension strip 171 by laser engraving. The microlens array 1713 fits snugly against the curved surface of the arc-shaped end face 1711. The convex surface of each microlens faces the light-emitting side of the light guide plate 100, ensuring the consistency of the light refraction direction. Its surface roughness Ra≤0.05μm ensures the smoothness of light propagation and reduces stray reflection loss. The microlens array 1713 on the arc-shaped end face 1711 further collimates and widens the angle of refraction of diffuse reflected light, improving the brightness of the emitted light while expanding the viewing angle, so that the displayed image maintains a uniform and soft visual effect at different angles.

[0033] In this embodiment, the first scattering structure 160 on the first side 140 of the light guide plate 100 adopts a scattering hole 161 design with gradually increasing aperture, depth, and density from the light incident end towards the center position 130. This, combined with the second scattering structure 170 on the second side 150 with a first inclined surface 180, works synergistically to disrupt total internal reflection from both sides. This avoids the uneven light output caused by a single scattering structure in existing technologies, significantly improving the overall light output uniformity of the light guide plate 100 and meeting the optical requirements of high-definition displays in large-size televisions. Furthermore, by setting the first aperture segment 1611, the second aperture segment 1612, and the third aperture segment 1613, light undergoes multiple refractions and diffuse reflections within the scattering hole 161, further disrupting directional total internal reflection while avoiding stray light reflection and improving the purity of the emitted light. Finally, the extension strip 171 of the second scattering structure 170 is provided with an arc-shaped end face 1711 and two inclined end faces 1712 on both sides. The inclination angle of the inclined end face 1712 gradually increases from the light-incident end to the center position 130, which is adapted to the thickness gradient characteristics of the light guide plate 100, so that the light is smoothly refracted along the inclined surface. The micron-level hemispherical microlens array 1713 protruding on the arc-shaped end face 1711 collimates and refracts the diffuse reflected light at a wide angle, effectively improving the output brightness while ensuring the uniformity of light output, and at the same time expanding the light output angle and improving the visual experience of the display screen.

[0034] Please refer to Figure 5 A second objective of the present invention is to provide a method for processing a light guide plate 100, for preparing the aforementioned light guide plate 100, the method comprising: S1. The light guide plate 100 substrate is molded using injection molding process, and the first scattering structure 160 is integrally formed. For example, when preparing the light guide plate 100, the light guide plate 100 substrate and the first scattering structure 160 are processed using an integrated injection molding process. Specifically, a high-transmittance optical resin, such as PMMA or PC, is heated and melted into a liquid state, and then injected into a pre-set precision injection mold cavity. After pressure holding, cooling, and solidification, a light guide plate 100 with a first end 110, a second end 120, a center position 130, a first side 140, and a second side 150 is formed in one step. Furthermore, the light guide plate 100 substrate with the first inclined surface 180 on the second side 150, and a first scattering structure 160 containing multiple rows of uniformly distributed scattering holes 161, are integrally formed on the first side 140 of the light guide plate 100 substrate. The first hole segment 1611, the second hole segment 1612, the third hole segment 1613 of the scattering holes 161, as well as the circumferentially spaced protrusions 162 in the second hole segment 1612 and the micro-nano frosted textures 1614 in the third hole segment 1613, are all integrally formed by the cavity and insert structure of the injection mold, without the need for subsequent secondary processing. The integral molding ensures the continuity of the light guide medium, eliminates structural losses in light propagation, and avoids damage from secondary processing, maintaining the surface integrity of the optical structure and preventing the generation of stray light. When light propagates inside the light guide plate 100 and interacts with the first scattering structure 160, it will not cause stray reflection or refraction loss due to discontinuity of the medium or structural steps, nor will it cause local deflection of the light due to the air layer at the gap. This ensures that the light propagates stably along the designed path and avoids the formation of dark areas due to local light loss, thus ensuring the uniformity of light propagation at the medium level.

[0035] S2. Using a first-power laser, the basic outline of the extension strip 171 is engraved on the second side 150 of the light guide plate 100 substrate, so that the extension strip 171 forms an arc-shaped end face 1711 and an inclined end face 1712. For example, the first-power laser is a high-power laser, specifically 50-80W. The first power is used to engrave the basic outline of the extension strip 171, forming multiple basic outlines of the extension strip 171 distributed in an array, so that the end of the extension strip 171 away from the first side 140 forms an arc-shaped end face 1711, and an inclined end face 1712 is engraved on the adjacent two sides of the arc-shaped end face 1711.

[0036] S3. Using a second-power laser, a microlens array 1713 is engraved on the arc-shaped end face 1711 of the extension strip 171 to complete the processing of the second scattering structure 170, resulting in the finished light guide plate 100; wherein, the first power is greater than the second power. For example, a low-power laser is selected for the second power, specifically a laser with a power between 10-20W. Fine engraving is performed on the arc-shaped end face 1711 of the extension strip 171 to form a micron-scale hemispherical microlens array 1713 protruding from the arc-shaped end face 1711.

[0037] Please refer to Figure 6The light guide plate 100 of this invention is manufactured using a composite process of injection molding and laser layer engraving. Injection molding, through precise replication of mold inserts, ensures the structural integrity, parameter consistency, and medium continuity of the first scattering structure 160. This allows light to undergo a complete process of stable light guiding, circumferential scattering, and micro-nano diffuse reflection within the scattering hole 161, precisely balancing the overall luminous flux according to the rule of weak scattering at the edges and strong scattering at the center. Laser layer engraving, through a high-power molding extension strip 171 macroscopic constraint structure and a low-power engraved microlens micro-light homogenizing unit, achieves secondary optimization of the light. The power differentiation design avoids structural processing damage, ensuring differentiated control effects of edge divergence and central collimation of the microlens. Together, these two processes form a complete optical control system with macroscopic uniform distribution and microscopic precise light homogenization, which is beneficial for improving light output uniformity, brightness gain, and viewing angle expansion. Simultaneously, it adapts to the needs of industrial mass production, ensuring product yield and performance stability.

[0038] To verify the light output uniformity, brightness gain, and viewing angle expansion effect of the light guide plate 100 of the present invention, and to clarify the technical advantages of this solution, the following experiments were conducted: The light guide plate 100 prepared by the experimental group using the structure and processing method of the light guide plate 100 described above in this invention was a mainstream 55-inch size, made of optical grade PMMA. The core parameters are as follows: maximum thickness D of light guide plate 100 = 4.0 mm; depth range H of scattering hole 161 ∈ [0.4 mm, 1.0 mm]; taper of third hole segment 1613 = 1.3 × taper of second hole segment 1612; height range of bump 162 = 0.08-0.15 mm; tilt angle range of extension strip 171 = 6°-13°; microlens diameter = 150-250 μm; convex surface height = 40-60 μm.

[0039] The control group used a light guide plate 100 with publication number CN110879436A. Its size and material were the same as those of the experimental group. It only had a single scattering dot structure and no optimized designs such as three-level apertures, bumps 162, or microlens arrays 1713.

[0040] Table 1. Comparison of 100 Core Optical Performance Tests of Light Guide Plates in Experimental and Control Groups The experimental group exhibited a global brightness difference of only 3.9%, significantly lower than the control group's 12.7%, demonstrating that the synergistic design of the three-stage aperture segment, bump 162, micro / nano texture, and microlens array 1713 effectively disperses concentrated light and supplements the central luminous flux, achieving uniform light output across the entire area. The experimental group's luminous flux increased by 11.8% compared to the control group, indicating that the structural optimization of this scheme did not cause light loss; instead, the design, including microlens collimation and the reflective film 240, improved light utilization. The experimental group achieved a light output angle of 172°, 40.7% wider than the control group, verifying the wide-angle refraction effect of the microlens array 1713 and the inclined end face 1712 of the extension strip 171. The experimental group's edge light leakage rate was only 2.8%, significantly lower than the control group's 10.5%, demonstrating that the synergistic effect of the third aperture segment 1613 and the edge light-blocking structure effectively reduced light escape.

[0041] A third objective of this invention is to provide a backlight panel 200, comprising a housing 210, LED strips 220, a diffuser film 230, a reflective film 240, and the aforementioned light guide plate 100. A mounting cavity 211 is formed on the housing 210. The LED strips 220, diffuser film 230, reflective film 240, and light guide plate 100 are all disposed within the mounting cavity 211. The reflective film 240 is disposed on a first side 140 of the light guide plate 100, and the diffuser film 230 is disposed on a second side 150 of the light guide plate 100. Two LED strips 220 are respectively disposed at a first end 110 and a second end 120 of the light guide plate 100. Exemplarily, the mounting cavity 211 is a rectangular cavity, and two LED strips 220 are provided, one at the first end 110 and the other at the second end 120. The light emitted by the LED strips 220 is diffusely reflected by the first scattering structure 160 and the second scattering structure 170, and then reflected by the reflective film 240 before being emitted towards the first side 140. After light rays are incident on the light strip 220 from the first end 110 and the second end 120 of the light guide plate 100, they first enter the scattering hole 161 on the first side 140: the light is stably guided by the first aperture segment 1611, the protrusion 162 of the second aperture segment 1612 disperses the light circumferentially, and then further diffuses the concentrated light by the micro-nano frosted texture 1614 and the expansion taper of the third aperture segment 1613, thus scattering the concentrated light in all directions. After the light propagates inside the light guide plate 100 to the second side 150, it is first constrained by the array extension strip 171: the small-angle inclined end face 1712 in the edge area reduces light loss, the large-angle inclined end face 1712 in the center area enhances refraction, and the arc-shaped end face 1711 further disperses the light; finally, the micron-level microlens array 1713 on the end face performs precise control, the edge light is diffused and depressurized, and the center light is collimated and supplemented, ultimately achieving uniform light output across the entire area.

[0042] Example 2: like Figure 7 As shown, the main difference between this embodiment and Embodiment 1 is that the first inclined surface 180 is provided with multiple angles. Specifically, it is reflected in: like Figure 7 As shown, in the directions from the first end 110 toward the center position 130 and from the second end 120 toward the center position 130, the first inclined surface 180 is set with three angles, denoted as γ1, γ2, and γ3, which increase sequentially, where γ1 = 6°, γ2 = 10°, and γ3 = 13°. Setting the first inclined surface 180 with three progressively increasing angles of 6°, 10°, and 13° conforms to the natural distribution characteristics of the light guide plate 100, which has a gradual change in thickness and a light density that decreases from high to low. The gradient angles adapt to the light distribution, accurately balance the luminous flux across the entire area, significantly improve the uniformity of light output, and the reasonable angle increments avoid the generation of stray light, improving the purity of the output light. It works in deep collaboration with the second scattering structure 170 to form a dual-layer optical control, enhancing the uniform light effect. The three gradient angles of the first inclined surface 180 and the angle of the inclined end face 1712 of the extension strip 171 of the second scattering structure 170 are matched with the same gradient. The two form a two-layer optical control system with macroscopic refraction of the inclined surface and precise constraint of the extension strip 171 on the second side 150 of the light guide plate 100.

[0043] Apart from the differences mentioned above, the structures of the light guide plate 100, backlight plate 200 and their associated components provided in this embodiment can be optimized with reference to Embodiment 1, and will not be described in detail here.

[0044] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of the patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these all fall within the scope of protection of the present invention. Therefore, the scope of protection of this patent should be determined by the appended claims.

Claims

1. A double-sided, highly uniform light guide plate with high light scattering, characterized in that, Including the first end, the second end, the center, the first side, and the second side; A first scattering structure is disposed on the first side. The first scattering structure includes a plurality of scattering holes evenly distributed in multiple rows. The aperture, depth, and density of the scattering holes gradually increase in the direction from the first end toward the center position and from the second end toward the center position. The maximum thickness of the light guide plate is denoted as D, the maximum depth of the scattering holes is denoted as H1, and the minimum depth of the scattering holes is denoted as H2. H1 and H2 are both within the range of [1 / 10D, 1 / 4D]. The aperture change, depth change, and spacing change of two adjacent scattering holes are K1, K2, and K3, respectively, wherein the values ​​of K1, K2, and K3 decrease sequentially. The second scattering structure is disposed on the second side, and the second side is provided with a first inclined surface so that the thickness of the light guide plate gradually decreases in the direction from the first end toward the center position and from the second end toward the center position.

2. The double-sided scattering high-uniformity light guide plate according to claim 1, characterized in that, Let the density of the scattering aperture be M, then ; in, This represents the radius of the scattering aperture. This represents the horizontal distance between the centers of two adjacent scattering apertures in the same row. This represents the vertical distance between the centers of two adjacent rows of scattering apertures, and and All are variables.

3. The double-sided scattering high-uniformity light guide plate according to claim 1, characterized in that, The scattering aperture includes a first aperture segment, a second aperture segment, and a third aperture segment, which are connected sequentially. In the direction from the first aperture segment to the third aperture segment, the aperture of the second aperture segment extends with a gradually decreasing trend, and the aperture of the third aperture segment extends with a gradually increasing trend.

4. The double-sided scattering high-uniformity light guide plate according to claim 3, characterized in that, The light guide plate also includes a plurality of protrusions extending from the second aperture segment, the plurality of protrusions being distributed circumferentially around the axis of the second aperture segment.

5. The double-sided scattering high-uniformity light guide plate according to claim 3, characterized in that, The inner surface of the third hole segment has a micro-nano frosted texture; and the taper of the third hole segment is configured to be 1.2-1.5 times that of the taper of the second hole segment.

6. The double-sided scattering high-uniformity light guide plate according to claim 3, characterized in that, The second scattering structure includes multiple extended strips arranged in an array.

7. The double-sided scattering high-uniformity light guide plate according to claim 6, characterized in that, The end of the extension strip opposite to the first side has an arc-shaped end face, and the adjacent two sides of the arc-shaped end face of the extension strip have inclined end faces. The inclination angle of the inclined end faces gradually increases in the direction from the first end toward the center position and from the second end toward the center position.

8. The double-sided scattering high-uniformity light guide plate according to claim 7, characterized in that, The arc-shaped end face is formed with a microlens array, which is configured as a micron-scale hemispherical structure that protrudes from the arc-shaped end face and is distributed in an array.

9. A method for processing a light guide plate, used to prepare the light guide plate as described in any one of claims 1-8, characterized in that, The method includes: S1. The light guide plate substrate is formed by injection molding and the first scattering structure is formed integrally. S2. Using a first-power laser, the basic outline of the extension strip is engraved on the second side of the light guide plate substrate, so that the extension strip forms an arc end face and an inclined end face; S3. A microlens array is engraved on the arc-shaped end face of the extension strip using a second power laser to complete the processing of the second scattering structure and obtain the finished light guide plate; wherein, the first power is greater than the second power.

10. A backlight panel, characterized in that, The light guide plate includes a housing, light strips, a diffusion film, a reflective film, and a light guide plate as described in any one of claims 1-8. The housing has a mounting cavity, and the light strips, the diffusion film, the reflective film, and the light guide plate are all disposed within the mounting cavity. The reflective film is disposed on the first side of the light guide plate, the diffusion film is disposed on the second side of the light guide plate, and the two light strips are respectively disposed at the first end and the second end of the light guide plate.

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