Partition-controlled light guide plate

Abstract

The utility model relates to the technical field of light guide plates, in particular to a light guide plate with zone control, which comprises a light source, a light-in surface, a light-out surface and a lattice point surface opposite to the light-out surface, the light-in surface is opposite to the light-out surface of the light source, and the light-out surface, the lattice point surface and the light-in surface are vertically connected; the light emitting surface is provided with columnar array structures, the columnar structures extend in the direction perpendicular to the light incident surface and are sequentially arranged in the direction parallel to the light incident surface to form a continuous columnar curved surface, and the lattice point surface comprises prism structures and triangular prism lattice point structures which are arranged in an array mode in the direction parallel to the light incident surface. According to the utility model, the lattice point surface and the light-emitting surface microstructure of the light guide plate are designed to realize visual angle contraction and light collimation. The light propagation direction and the light emitting area are regulated and controlled, and it is ensured that light is emitted in a specific partition and does not interfere with one another. And the multifunctional backlight module with regional light splitting control is formed by matching with different backlight diaphragms.

Description

Technical Field

[0001] The utility model relates to the technical field of light guide plates, and particularly relates to a light guide plate with zonal control. Background Art

[0002] Augmented reality (AR) technology can superimpose virtual content on the real environment, while virtual reality (VR) technology can completely replace the real environment with a virtual environment. These two cutting-edge technologies have shown great development potential in many fields such as gaming, medical care, and education, and are expected to completely change our ways of living, working, and communicating in the future. With the rapid progress of VR product applications, the corresponding display devices are also facing urgent demands for higher brightness, higher contrast, and thinner thickness. Therefore, backlight designs with diverse functions have become one of the current research hotspots.

[0003] Traditional side-entry backlights mainly rely on dot patterns in the light guide plate to break the total internal reflection process of light, enabling the light to scatter out of the light guide plate at the dot patterns, thereby achieving the function of deflecting light from the side to the front. However, in conventional light guide plate products, due to the relatively large front light-emitting angle after the light passes through the dot scattering, the backlight brightness is relatively low. To ensure the uniformity of light emission from the light guide plate, the dots are usually arranged randomly. However, in the case of irregular dot scattering, it is difficult for side-entry backlights to achieve precise zonal light splitting control. Summary of the Utility Model

[0004] Aiming at the deficiencies of the prior art, the utility model discloses a light guide plate with zonal control and its backlight module, aiming to optimize the large-angle front light emission of a conventional light guide plate into axially collimated light, while regulating the light propagation direction and light-emitting area in the light guide plate, enabling the light to be emitted within specific zones, and the light in different zones does not interfere with each other. A new type of functional light guide plate with high brightness and zonal light splitting control is obtained.

[0005] The utility model is realized through the following technical solutions:

[0006] In a first aspect, the utility model provides a light guide plate with zonal control, including a light source, a light-incident surface, a light-emitting surface, and a dot surface opposite to the light-emitting surface, wherein the light-incident surface is opposite to the light-emitting surface of the light source, and the light-emitting surface, the dot surface are perpendicularly connected to the light-incident surface; characterized in that, the light-emitting surface is provided with a columnar array structure, the columnar array structure extends in a direction perpendicular to the light-incident surface and is arranged in sequence along a direction parallel to the light-incident surface, forming a continuous columnar curved surface, and the dot surface includes a prism structure and a triangular prism dot structure arranged in an array along a direction parallel to the light-incident surface.

[0007] Furthermore, the triangular prism dot structures are arranged according to the Bessel equation distribution.

[0008] Further, the prism structure extends in a direction perpendicular to the light incident surface and is recessed from the surface of the dot surface towards the light exit surface.

[0009] Further, the triangular prism dot structure is recessed from the surface of the dot surface towards the light exit surface, and the two triangular prism surfaces are perpendicular to the light incident surface.

[0010] In a second aspect, the present invention provides a backlight module with zonal control, which is loaded with the light guide plate with zonal control described in the first aspect.

[0011] The beneficial effects of the present invention are as follows:

[0012] By designing the microstructures of the dot surface and the light exit surface of the light guide plate, the present invention realizes the contraction of the viewing angle and the collimation of light; by regulating the propagation direction and the light exit area of the light in the light guide plate, it is ensured that the light is emitted only within specific zones, and the light in different zones does not interfere with each other; for different application requirements, different backlight films are matched, thus forming a set of multifunctional backlight modules that can achieve zonal light splitting control. Description of the Drawings

[0013] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0014] Figure 1 It is a schematic diagram of the structure of the light guide plate in the embodiment of the present invention;

[0015] Figure 2 It is a schematic diagram of the light propagation trajectory in the light guide plate in the embodiment of the present invention;

[0016] Figure 3 It is a schematic diagram of the light propagation trajectory of the dot surface of the light guide plate in the embodiment of the present invention;

[0017] Figure 4 It is a schematic diagram of the light propagation trajectory in the light guide plate in the embodiment of the present invention;

[0018] Figure 5 It is a schematic diagram of the continuous columnar curved surface structure in the embodiment of the present invention;

[0019] Figure 6 It is a schematic diagram of the dot structure in the embodiment of the present invention;

[0020] Figure 7 It is a schematic diagram of the prism structure in the embodiment of the present invention;

[0021] Figure 8 is the conventional backlight illumination distribution diagram of the embodiment of the present utility model;

[0022] Figure 9 is the front illumination distribution when only a single partition of the backlight module using the functional light guide plate of the embodiment of the present utility model is turned on. Detailed implementation manners

[0023] To make the objectives, technical solutions and advantages of the embodiments of the present utility model clearer, the technical solutions in the embodiments of the present utility model will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present utility model. Apparently, the described embodiments are some but not all of the embodiments of the present utility model. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present utility model without creative efforts shall fall within the protection scope of the present utility model.

[0024] The present embodiment provides a light guide plate 100 as Figure 1 shown, which includes a light incident surface 101, a light exit surface 102, and a dot surface 103 opposite to the light exit surface. Among them, the surface opposite to the light emitting surface of the light source 200 (LED) is the light incident surface, and the light exit surface and the dot surface are vertically connected to the light incident surface. A columnar array structure is provided on the light exit surface of the light guide plate. The columnar array structure extends in the direction perpendicular to the light incident surface (D1) and is arranged in sequence in the direction parallel to the light incident surface (D2) to form a continuous columnar curved surface 110; the dot surface of the light guide plate includes a prism structure 120 arranged in an array in the D2 direction and a triangular prism dot structure 130 arranged in a mathematical pattern. The prism structure extends in the D1 direction and is recessed from the surface of the dot surface towards the light exit surface in the D3 direction; the triangular prism dot structure is recessed from the surface of the dot surface towards D3, and the two triangular prism surfaces are perpendicular to the light incident surface.

[0025] The dots of the conventional light guide plate are mostly spherical Dot dots. When light is incident on the Dot dots, scattering will occur at the dots, converting the horizontally propagating LED surface light source into individual dot light sources on the dot surface. At this time, the light will be scattered out of the light guide plate at a large angle.

[0026] As Figure 2 shown in the new type of functional light guide plate, the dot structure is designed as an isosceles triangular prism, and the two prism side surfaces face the light incident surface of the light guide plate and the included angle with the dot surface is α. The incident light propagating in the light guide plate is reflected once or several times by the prism side surface at an angle of α, which can effectively reduce the exit angle of the reflected light. At the same time, the reflection plane facing the light incident surface ensures that the reflected light is always in the plane formed by the incident light and the normal line of the reflection surface.

[0027] As Figure 3As shown, the dot pitch is provided with a prism structure arranged in an array. The height of the prism is greater than the height of the dot, which can effectively block the large-angle incident light and reflected light deviating from the propagation direction. Therefore, the orientation of the light propagating in the light guide plate as a whole remains from the incident end to the far end, and the light exit position is limited to the light guide plate interval opposite to the two light sources. As Figure 4 As shown, the large-angle outgoing light in the D3 direction (including the reflected light of the prism structure and the dots, and the large-angle emitted light of the LED) has a significant improvement in the collimation of the outgoing light after passing through the prism curved surface structure 110 (the light converging effect of the convex lens).

[0028] Figure 5 The figure shows a continuous cylindrical cross-section. The continuous cylindrical curve is formed by the continuous alternating intersection of arcs (radius R1) and arcs (radius R2). The center of R1 is inside the light guide plate, and the center of R2 is outside the light guide plate, 20um ≤ R1 ≤ 100um, R2 ≤ 5um.

[0029] Figure 6 The figure shows a triangular prism dot. The angle between the inclined plane and the bottom surface of the prism is α (here the side surface of the prism is an isosceles triangle because the light guide plate is double-sidedly illuminated. If the light guide plate is single-sidedly illuminated, the shape of the side surface of the prism can be a right triangle, etc.), and 1 / 2(90° - θ1 / 2) < α < 45°); the edge length L2 of the triangular prism = k * cotα (mm), (0.006 ≤ k ≤ 0.04, k represents the height range of the dot (3um - 20um)); L1 = b * L2, (0 < b ≤ 3).

[0030] The position rule of the triangular prism dots on the dot surface of the light guide plate can be set according to the Bessel equation:

[0031]

[0032] Therefore, the light incident from the incident surface can be evenly reflected to the light exit surface, improving the uniformity of the brightness at each place on the light exit surface and further realizing a more uniform display screen. The arrangement rule of the triangular prism dots can also adopt different dot arrangement optimization methods according to different requirements, such as offset rectangle, radial polynomial, grid, list, etc. The present utility model does not limit this.

[0033] Figure 7 The figure shows a cross-section of the array prism structure. The cross-section of the prism is triangular (it can also be other shapes, such as rectangle, trapezoid, semi-circular, etc. The purpose of this structure is mainly to block the light from propagating outside the area). The height H of the prism structure is greater than the depth of the triangular prism dots; the apex angle β of the triangle: 30° ≤ β ≤ 60°; 0.02mm ≤ W ≤ 0.2mm, and the prism structures are arranged at equal intervals on the dot surface.

[0034] Figure 9When only a single partition of the functional light guide plate backlight module is turned on, the front illumination intensity distribution is shown as follows. Compared with the conventional backlight illumination intensity distribution as shown in Figure 8 The functional light guide plate backlight module can control the light to emit within this partition and will not interfere with the illumination intensity distribution of other areas. Therefore, an obvious contrast between light and darkness can be formed between the lit partition and the unlit partition (define η as the partition interference rate, calculation method: the central brightness of the partition adjacent to the target partition / the central brightness of the target partition). The partition interference rate η of the backlight module is less than 50%, and with the backlight drive control, the partition control function of the display is realized.

[0035] In summary, the present utility model realizes the contraction of the viewing angle and the collimation of light by carefully designing the dot surface and the light-emitting surface microstructure of the light guide plate; by regulating the propagation direction and the light-emitting area of the light in the light guide plate, it ensures that the light is only emitted within a specific partition and the light in different partitions does not interfere with each other; for different application requirements, different backlight films are matched, thus forming a set of multifunctional backlight modules that can achieve regional light splitting control.

[0036] The above embodiments are only used to illustrate the technical solutions of the present utility model and are not intended to limit them; although the present utility model has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions recorded in the foregoing embodiments or equivalently replace some of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present utility model.

Claims

1. A zone-controlled light guide plate, comprising a light source, a light incident surface, a light emitting surface, and a dot surface opposite to the light emitting surface, wherein the light incident surface is opposite to the light emitting surface of the light source, and the light emitting surface and the dot surface are vertically connected to the light incident surface; characterized in that: The light emitting surface is provided with a columnar array structure, which extends in a direction perpendicular to the light incident surface and is arranged in sequence along a direction parallel to the light incident surface to form a continuous columnar curved surface. The grid point surface includes a prism structure and a triangular prism grid point structure arranged in an array along a direction parallel to the light incident surface.

2. The zone-controlled light guide plate according to claim 1, characterized in that: The triangular prism grid point structure is arranged according to the Bessel equation distribution.

3. The zone-controlled light guide plate according to claim 1, characterized in that: The prism structure extends in a direction perpendicular to the light incident surface and is recessed from the surface of the grid point surface toward the light emitting surface.

4. The zone-controlled light guide plate according to claim 1, characterized in that: The triangular prism dot structure is concave from the dot surface toward the light emitting surface, and the two triangular cylinders are perpendicular to the light incident surface.

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