Backlight module, display panel and display device

Abstract

Embodiments of the present application relate to a backlight module, a display panel and a display device, the backlight module comprising: at least one layer of transmission medium, a back plate, a light emitting module, the light emitting module being arranged on the back plate, the at least one layer of transmission medium being spaced apart by a support by a preset distance; light emitted by the light emitting module is incident on the at least one layer of transmission medium at Brewster's angle, and after passing through the at least one layer of transmission medium, linearly polarized light with a target polarization direction is emitted. Embodiments of the present application effectively utilize the Brewster's angle in optical technology, so that all or most of the light transmitted through the at least one layer of transmission medium is linearly polarized light, thereby realizing effective control of the polarization state of the light incident on the liquid crystal panel. The emitted linearly polarized light can be completely incident into the liquid crystal panel, thereby improving the energy utilization rate of the backlight module.

Description

Technical Field

[0001] This application relates to the field of display panel technology, and in particular to a backlight module, display panel and display device. Background Technology

[0002] Current display panel backlight sources typically use ordinary circularly polarized light, which is close to the form of natural light, to form a liquid crystal module when combined with an LCD panel. Usually, a polarizer that allows linearly polarized light to pass through is attached to the surface of the LCD panel. Therefore, when non-linearly polarized light incident from the outside passes through the polarizer, only the light rays with polarization parallel to the polarizer on the LCD panel can enter the LCD panel. This means that most of the backlight cannot effectively pass through the LCD panel, resulting in low energy utilization of the backlight source. Summary of the Invention

[0003] In view of this, in order to solve some or all of the above-mentioned technical problems, embodiments of this application provide a backlight module, a display panel, and a display device.

[0004] In a first aspect, embodiments of this application provide a backlight module, which includes: at least one layer of transmission medium, a back plate, and a light-emitting module, wherein the light-emitting module is disposed on the back plate; the light emitted by the light-emitting module is incident on at least one layer of transmission medium at Brewster angle, and after passing through at least one layer of transmission medium, it is emitted as linearly polarized light with a target polarization direction.

[0005] In one possible implementation, the number of layers of the at least one transmission medium is greater than or equal to two, and adjacent layers of the transmission medium are spaced a predetermined distance apart by a support.

[0006] In one possible implementation, the light-emitting unit includes a light-emitting diode (LED) and a transparent colloid, with the transparent colloid wrapping around the LED. At each cross-section containing the LED's principal optical axis, for light emitted by the LED within a preset angle range, if the angle between the light ray and the principal optical axis is a Brewster angle, then at the intersection of the light ray and the light-emitting surface of the transparent colloid, the tangent of the transparent colloid surface is perpendicular to the light ray. If the angle between the light ray and the principal optical axis is not a Brewster angle, then at the intersection of the light ray and the light-emitting surface of the transparent colloid, with the tangent at the intersection as the medium interface, the light ray is refracted at the medium interface and incident on at least one layer of transmission medium at a Brewster angle.

[0007] In one possible implementation, the light-emitting unit includes a light-emitting diode and a lens, with the lens encasing the light-emitting diode; the lens includes a central reflecting surface and an outer transmitting surface, wherein light emitted by the light-emitting diode onto the central reflecting surface is reflected onto the outer transmitting surface; for light reflected onto the outer transmitting surface, at the intersection of the light ray and the outer transmitting surface, with the tangent plane at the intersection point as the medium interface, the light ray is refracted at the medium interface and incident on at least one layer of transmitting medium at Brewster angle.

[0008] In one possible implementation, the outer transmissive surface includes a first transmissive surface and a second transmissive surface. The angle between the cross-section of each point on the first transmissive surface and the principal optical axis of the light-emitting diode is within a first preset angle range, so that the light emitted by the light-emitting diode onto the first transmissive surface undergoes total internal reflection on the first transmissive surface, and is then reflected onto the central reflective surface, and reflected back to the first transmissive surface by the central reflective surface. For the light reflected onto the first transmissive surface, at the intersection of the light and the first transmissive surface, the cross-section at the intersection point serves as the medium interface, and the light is refracted at the medium interface, incident on at least one layer of transmissive medium at a Brewster angle. For the light emitted by the light-emitting diode onto the second transmissive surface, at the intersection of the light and the second transmissive surface, the cross-section at the intersection point serves as the medium interface, and the light is refracted at the medium interface, incident on at least one layer of transmissive medium at a Brewster angle.

[0009] In one possible implementation, the angle between the cross section of each point on the central reflective surface and the principal optical axis of the light-emitting diode is within a second preset angle range, so that the light emitted by the light-emitting diode onto the central reflective surface undergoes total internal reflection on the central reflective surface, is then reflected to the outer transmission surface, is refracted by the outer transmission surface, and is incident on at least one layer of transmission medium at Brewster angle.

[0010] In one possible implementation, a reflective coating is provided on the central reflective surface. The reflective coating is used to reflect light emitted onto the central reflective surface to the outer transmission surface, where it is refracted and incident at Brewster angle onto at least one layer of transmission medium.

[0011] In one possible implementation, at least one layer of the transmissive medium has three layers, the support is a transparent adhesive strip, and the transmissive media are spaced at a predetermined distance by the transparent adhesive strip.

[0012] In one possible implementation, the backplate is provided with a reflective coating for reflecting light reflected by at least one layer of the transmission medium back to at least one layer of the transmission medium.

[0013] Secondly, embodiments of this application provide a display panel, which includes a liquid crystal panel and a backlight module described in the first aspect above, wherein the backlight module emits linearly polarized light in a target polarization direction to the liquid crystal panel.

[0014] Thirdly, embodiments of this application provide a display device, including: the display panel described in the second aspect above.

[0015] The backlight module, display panel, and display device provided in this application embodiment involve setting at least one layer of transmissive medium, a back plate, and a light-emitting module. The at least one layer of transmissive medium is spaced a predetermined distance apart by a support. The light-emitting module is disposed on the back plate. Light emitted from the light-emitting module is incident on the at least one layer of transmissive medium at a Brewster angle, and after passing through the at least one layer of transmissive medium, it exits as linearly polarized light with a target polarization direction. This application embodiment effectively utilizes the Brewster angle in optical technology, ensuring that all or most of the light transmitted through the at least one layer of transmissive medium is linearly polarized light. This achieves effective control over the polarization state of the light incident on the liquid crystal panel, allowing the emitted linearly polarized light to completely penetrate the liquid crystal panel, thus improving the energy utilization rate of the backlight module. Attached Figure Description

[0016] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application.

[0017] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, for those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] One or more embodiments are illustrated by way of example with reference numerals in the accompanying drawings. These illustrations do not constitute a limitation on the embodiments. Elements with the same reference numerals in the drawings are denoted as similar elements. Unless otherwise stated, the figures in the drawings are not to be limited by scale.

[0019] Figure 1 This is a schematic diagram of the backlight module provided in an embodiment of this application;

[0020] Figure 2A This is a schematic diagram of the polarization state of circularly polarized light.

[0021] Figure 2B This is a schematic diagram of the polarization state of linearly polarized light.

[0022] Figure 3 This is a schematic diagram of the backlight module provided in an embodiment of this application;

[0023] Figure 4 This is a schematic diagram of the structure of a light-emitting unit provided in an embodiment of this application;

[0024] Figure 5 A schematic diagram of the light distribution on a cross section including the main optical axis of the light-emitting unit, provided for an embodiment of this application;

[0025] Figure 6 This is a schematic diagram of another light-emitting unit provided in an embodiment of this application;

[0026] Figure 7 A schematic diagram of the light distribution on a cross section containing the main optical axis of the light-emitting unit, provided for an embodiment of this application;

[0027] Figure 8 This is a schematic diagram of the structure of a display panel provided in an embodiment of this application;

[0028] Figure 9 This is a schematic diagram of the structure of a display device provided in an embodiment of this application.

[0029] Figure label:

[0030] 100 - Backlight module; 101 - At least one layer of transmissive medium; 102 - Back plate; 103 - Light-emitting module; 1031 - Transparent colloid; 1032 - Light-emitting diode; 1033 - Lens; 10331 - Central reflective surface; 10332 - Outer transmissive surface; 103321 - First transmissive surface; 103322 - Second transmissive surface; 800 - Display panel; 801 - Liquid crystal panel; 8011 - Polarizer; 901 - Panel frame; 902 - Power module; 903 - Data receiving module. Detailed Implementation

[0031] Various exemplary embodiments of this application will now be described in detail with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them. It should be noted that, unless otherwise specifically stated, the relative arrangement, numerical expressions, and values ​​of the components and steps set forth in these embodiments do not limit the scope of this application.

[0032] Those skilled in the art will understand that the terms "first" and "second" in the embodiments of this application are only used to distinguish different steps, devices or modules, and do not represent any specific technical meaning, nor do they indicate the logical order between them.

[0033] It should also be understood that in this embodiment, "multiple" can refer to two or more, and "at least one" can refer to one, two or more.

[0034] It should also be understood that any component, data or structure mentioned in the embodiments of this application can generally be understood as one or more unless explicitly defined or given contrary guidance in the context.

[0035] Furthermore, the term "and / or" in this application is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or B existing alone. Additionally, the character " / " in this application generally indicates that the preceding and following related objects have an "or" relationship.

[0036] It should also be understood that the description of the various embodiments in this application emphasizes the differences between the various embodiments, and the similarities or similarities can be referred to each other. For the sake of brevity, they will not be described in detail.

[0037] The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit the scope of this application and its application or use.

[0038] Techniques, structures, and equipment known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, structures, and equipment should be considered part of the specification.

[0039] It should be noted that similar labels and letters in the following figures indicate similar items; therefore, once an item is defined in one figure, it does not need to be discussed further in subsequent figures.

[0040] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. To facilitate understanding of the embodiments of this application, the application will be described in detail below with reference to the accompanying drawings and embodiments. Obviously, the described embodiments are only some, not all, of the embodiments of this application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the scope of protection of this application.

[0041] Figure 1 This is a schematic diagram of a backlight module 100 provided in an embodiment of this application. The backlight module 100 is typically used in display panels to provide backlight illumination for the liquid crystal panel within the display panel. Specifically, the backlight module 100 includes at least one layer of transmissive medium 101. Figure 1 The diagram shows a three-layer transmissive medium), a backplate 102, and a light-emitting module 103, with the light-emitting module 103 disposed on the backplate 102.

[0042] The material of at least one layer of the transmission medium 101 can be a material with high refractive index and high light transmittance. For example, it can be PET, PC, glass, etc. These materials have good optical uniformity and high light transmittance, which helps to increase the light intensity directed onto the liquid crystal panel.

[0043] In this embodiment, the light emitted by the light-emitting module 103 is incident on at least one layer of transmission medium 101 at Brewster angle, and after passing through at least one layer of transmission medium, it is emitted as linearly polarized light in the target polarization direction.

[0044] Figure 2A This is a schematic diagram illustrating the polarization state of circularly polarized light (natural light). Figure 2A It can be seen that the vibration trajectory of circularly polarized light is circular. Figure 2B This is a schematic diagram of the polarization state of linearly polarized light. Figure 2B It is known that the vibration trajectory of linearly polarized light is a straight line. Since the commonly used backlight module 100 emits circularly polarized light, and the polarizer on the LCD panel can only allow light parallel to its polarization direction to pass through, if the light incident on the LCD panel is circularly polarized light, some light will not be able to pass through, resulting in insufficient light intensity received and transmitted by the LCD panel.

[0045] Here, we first introduce the concept of Brewster's angle: When incident light travels from medium A to medium B, where the refractive index of A is n1 and the refractive index of B is n2, if the angle of incidence α satisfies tanα = n1 / n2, then this angle is defined as Brewster's angle. Light rays incident at Brewster's angle are reflected at the surface of medium B, and the polarization direction of the reflected light is perpendicular to the plane of incidence (the plane containing the incident light and the normal). After entering medium B, the light refracts, and most of the refracted light is polarized parallel to the plane of incidence, while a small portion is polarized perpendicular to it.

[0046] Optionally, the number of layers of the at least one transmissive medium 101 can be greater than or equal to two, and adjacent layers of the transmissive medium are spaced a predetermined distance apart by a support. According to the transmission characteristics of linearly polarized light, the more layers of the transmissive medium, the higher the content of linearly polarized light in a single polarization direction transmitted. Therefore, by providing at least two layers of transmissive medium, the light passing through at least two layers can be approximated as linearly polarized light, thereby making the light incident on the liquid crystal panel approximately linearly deflected light, increasing the light intensity transmitted from the liquid crystal panel.

[0047] Optionally, the number of layers of the at least one transmission medium 101 is three (i.e., as shown above). Figure 1 The three-layer transmission medium shown is supported by transparent adhesive strips, with each transmission medium separated by a predetermined distance. Based on the transmission characteristics of linearly polarized light, the more layers of transmission medium, the higher the content of linearly polarized light in a single polarization direction transmitted. However, too many layers of transmission medium increase the structural complexity of the backlight module 100 and lead to a decrease in light transmittance. Therefore, choosing three layers of transmission medium can balance the quality of linearly polarized light with the structural complexity of the actual product.

[0048] like Figure 3The diagram illustrates the principle of linearly polarized light generation by the backlight module 100 provided in this application. In this embodiment, the light emitted by the light-emitting module 103 is incident at an angle of Brewster's angle β onto at least one layer of transmission medium 101. Dots on the light rays in the diagram indicate polarization directions perpendicular to the incident surface, while line segments indicate polarization directions parallel to the incident surface. After passing through at least one layer of transmission medium 101, the majority of the incident light entering the liquid crystal panel is polarized parallel to the incident surface. Therefore, the light entering the liquid crystal panel can be considered linearly polarized light.

[0049] Since a polarizer is usually provided on the surface of an LCD panel, a polarizer parallel to the polarization direction of the incident linearly polarized light can be provided, so that the linearly polarized light can pass through the LCD panel completely, thereby improving the brightness of the LCD panel.

[0050] The light-emitting module 103 in this embodiment may include a light-emitting diode and a light-guiding device. The light-guiding device can change the emission angle of the light emitted by the light-emitting diode. For example, by setting a lens with a special structure on the light-emitting diode, covering it with a transparent colloid with a special structure, or setting a reflector, the light emitted by the light-emitting module 103 can be directed into at least one layer of transmission medium 101 at a Brewster angle.

[0051] The backlight module provided in this application embodiment comprises at least one layer of transmissive medium, a backplate, and a light-emitting module. The at least one layer of transmissive medium is spaced a predetermined distance apart by a support. The light-emitting module is disposed on the backplate. Light emitted from the light-emitting module is incident on the at least one layer of transmissive medium at a Brewster angle, and after passing through the at least one layer of transmissive medium, it exits as linearly polarized light in the target polarization direction. This application embodiment effectively utilizes the Brewster angle in optical technology, ensuring that all or most of the light transmitted through the at least one layer of transmissive medium is linearly polarized light. This achieves effective control over the polarization state of the light incident on the liquid crystal panel, allowing the emitted linearly polarized light to completely penetrate the liquid crystal panel, thus improving the energy utilization rate of the backlight module.

[0052] In some optional implementations of this embodiment, the light-emitting module 103 includes at least two light-emitting units, which are arranged in an array on the backplate 102, thereby making the light emitted from the backlight module 100 onto the liquid crystal panel more uniform.

[0053] In some optional implementations of this embodiment, such as Figure 4 As shown, each light-emitting unit in the light-emitting module 103 includes a light-emitting diode 1032 and a transparent colloid 1031, with the transparent colloid 1031 wrapping around the light-emitting diode.

[0054] In the light-emitting unit, the main optical axis of the light-emitting diode 1032 (e.g., Figure 5The straight line a shown is the main optical axis. It can be used as the axis and can determine an infinite number of cross sections within a 360° range. On each cross section containing the main optical axis of the light-emitting diode 1032, for the light emitted by the light-emitting diode 1032 within a preset angle range, if the angle between the light and the main optical axis is the Brewster angle, then at the intersection of the light and the light-emitting surface of the transparent colloid 1031, the cross section of the surface of the transparent colloid 1031 is perpendicular to the light.

[0055] If the angle between the ray and the principal optical axis is not Brewster's angle, then at the intersection of the ray and the light-emitting surface of the transparent colloid 1031, with the tangent at the intersection as the medium interface, the ray is refracted at the medium interface and incident on at least one layer of transmission medium 101 at Brewster's angle.

[0056] Specifically, the LED 1032 is typically a Lambertian light source, and its effective emission angle is defined as the angle corresponding to half of the maximum luminous intensity, usually 120°. Therefore, taking the emitting surface of the LED 1032 as a reference, the aforementioned angle range is 30°-150°. Within this range, light emitted from the transparent colloid 1031 into the air, that is, from an optically denser medium to an optically less dense medium, undergoes refraction in the air. For example... Figure 5 As shown, at each point on the light-emitting surface of the transparent colloid 1031, given that at least one layer of transparent medium is incident at a Brewster angle, the angle at which each incident ray is deflected on the light-emitting surface can be determined. Furthermore, according to the law of refraction (sinθ1 / sinθ2=n2 / n1, where θ1 is the angle of incidence, θ2 is the angle of refraction, n2 is the medium into which the light enters, and n1 is the medium into which the light exits), the cross-section of each point on the light-emitting surface can be determined. Based on the cross-sections at each point, the shape of the entire light-emitting surface of the transparent colloid 1031 can be determined. A light-emitting unit can be manufactured based on this shape.

[0057] Figure 5 The image shows the light distribution on a cross-section of the principal optical axis containing the light-emitting unit. Figure 5 It is known that the light-emitting unit emits a parallel beam of light, which enters at least one layer of light-transmitting medium at Brewster angle as the incident angle.

[0058] like Figure 5 As shown, the principal optical axis a is the normal direction of the light-emitting surface of the light-emitting diode 1032. Taking the light-emitting surface of the transparent colloid 1031 as the medium interface, at the intersection of the incident light i and the light-emitting surface of the transparent colloid 1031, the tangent at this point is set to be perpendicular to the incident light i. After the incident light i exits the light-emitting surface, it does not refract and is incident on at least one layer of transmission medium 101 along its original direction at Brewster angle β.

[0059] like Figure 5As shown, for a ray whose angle with the principal optical axis is not Brewster's angle, if the zigzag ray emitted from the medium interface is to enter at least one layer of the transmission medium 101 at a Brewster's angle β, the angle between the ray and the refracted ray can be determined. During the design phase of the transparent colloid 1031, this angle can be used as one of the constraints. Other conditions, such as the size limit of the transparent colloid 1031, the range of the emission angle, and the size of the emitting surface of the light-emitting diode 1032, can be set. By adjusting the angle between the tangent at the aforementioned intersection point of the transparent colloid 1031 and the ray, and according to the law of refraction, the refracted ray is made to enter at least one layer of the transmission medium 101 at a Brewster's angle β, thereby determining the shape and size characteristics of the transparent colloid 1031.

[0060] The incident angle θ of the ray relative to the interface of the incident medium satisfies the following relationship:

[0061] θ=90°-α-arctan(d / h) (1)

[0062] Where α is the angle between the ray and the light-emitting surface of the LED 1032, h is the height between the intersection point of the ray and the light-emitting surface of the transparent colloid 1031 and the light-emitting surface of the LED 1032, and d is the distance between the normal c of the ray and the projection point of the intersection point on the light-emitting surface.

[0063] like Figure 5 As shown, for any ray b, the ray intersects the light-emitting surface at point A. The perpendicular line from the tangent at point A is the normal c. The angle between c and b is the angle of incidence θ. According to the characteristics of a right triangle, the angle of incidence of the ray can be determined according to equation (1). By calculating the angles of incidence corresponding to multiple rays, the tangent at the intersection of each ray with the light-emitting surface 10321 can be determined. By combining these tangents, the shape of the light-emitting surface can be determined.

[0064] This embodiment wraps a transparent colloid around a light-emitting diode and pre-designs the shape of the transparent colloid so that the light-emitting unit can emit parallel light rays through refraction and into at least one layer of light-transmitting medium at Brewster angle. The light-emitting unit structure of this solution is compact, the manufacturing method is simple, and the installation stability and convenience of the light-emitting unit are higher, which helps to improve the overall stability and manufacturing efficiency of the backlight module.

[0065] In some optional implementations of this embodiment, such as Figure 6The diagram shows a cross-sectional schematic of the main optical axis containing the light-emitting unit. The light-emitting unit includes a light-emitting diode 1031 and a lens 1033, with the lens 1033 enclosing the light-emitting diode 1032. The lens 1033 includes a central reflecting surface 10331 and an outer transmitting surface 10332. Light emitted from the light-emitting diode 1032 onto the central reflecting surface 10331 is reflected onto the outer transmitting surface 10332.

[0066] Specifically, the aforementioned central reflective surface 10331 can be either a plane or a curved surface. A plane is simpler to manufacture and helps improve manufacturing efficiency. A curved surface allows for more precise control of the reflection angle of the reflected light, making the exit angle of the light rays more consistent with the desired angle.

[0067] For the light reflected onto the outer transmission surface 10332, at the intersection of the light and the outer transmission surface 10332, with the tangent plane where the intersection is located as the medium interface, the light is refracted at the medium interface and incident on at least one layer of transmission medium 101 at Brewster angle.

[0068] Once the direction of the reflected light on the central reflecting surface 10331 is known, and the desired direction of the reflected light that meets the Brewster angle requirement is known, the tilt angle of the tangent at each point on the outer transmission surface 10332 can be set according to the law of refraction, so that the light rays that hit the outer transmission surface 10332 are refracted and enter at least one layer of transmission medium 101 at the Brewster angle.

[0069] This embodiment designs the shape of the lens so that the light emitted by the light-emitting diode is reflected and refracted to obtain light that meets the Brewster angle requirement. This concentrates the light-emitting energy on one side of the central reflective surface, resulting in higher light intensity illuminating the liquid crystal panel, which helps to further improve the backlight brightness of the liquid crystal panel.

[0070] In some optional implementations of this embodiment, such as Figure 7The diagram illustrates the light distribution of the light-emitting unit. The outer transmissive surface 10332 includes a first transmissive surface 103321 and a second transmissive surface 103322. The angle between the cross-section of each point on the first transmissive surface 103321 and the principal optical axis a of the light-emitting diode 1032 is within a first preset angle range. This ensures that the light emitted by the light-emitting diode 1032 onto the first transmissive surface 103321 undergoes total internal reflection on the first transmissive surface 103321, is reflected back to the central reflective surface 10331, and then reflected back to the first transmissive surface 103321. After refraction at the first transmissive surface 103321, the light enters at least one layer of transmissive medium 101 at a Brewster angle. At the intersection of the light reflected onto the first transmissive surface 103321, the cross-section of the intersection serves as the medium interface. The light then refracts at this interface and enters at least one layer of transmissive medium 101 at a Brewster angle.

[0071] For the light emitted by the light-emitting diode 1032 onto the second transmission surface 103322, at the intersection of the light and the second transmission surface 103322, with the tangent plane where the intersection is located as the medium interface, the light is refracted at the medium interface and incident on at least one layer of transmission medium 101 at Brewster angle.

[0072] Specifically, the aforementioned first preset angle range is used to limit the tilt angle of the tangent at each point on the first transmission surface 103321, thereby limiting the incident angle of each ray of light illuminating the first transmission surface 103321, so that the incident angle is greater than the critical angle of total internal reflection.

[0073] like Figure 7 As shown, ray e strikes the first transmission surface 103321 at a point near the intersection with the second transmission surface 103322, where total internal reflection occurs. The formula for calculating the critical angle of total internal reflection is shown in equation (2) below:

[0074] sinθ1 / sinθ2=1 / n (2)

[0075] Where θ1 is the incident angle of the light ray entering the interface between the lens 1033 and the air, that is, the angle between the incident light ray and the normal of the interface, θ2 is the refraction angle, n is the refractive index of the lens 1033 material, and l is the refractive index of air.

[0076] The light ray f, after being reflected by the central reflecting surface 10331, is refracted again at the first transmitting surface 103321 and exits at a Brewster angle. When designing the shape of the first transmitting surface 103321, total internal reflection and the constraint that the outgoing light ray exits at a Brewster angle can be used as constraints to determine the shape of the first transmitting surface 103321. When designing the shape of the second transmitting surface 103322, it is only necessary to set the tangential tilt angle of each point on the second transmitting surface 103322, so that the light emitted by the light-emitting diode 1032 is refracted at the second transmitting surface 103322 and incident on at least one layer of transmitting medium 101 at a Brewster angle.

[0077] This embodiment, by setting a first transmission surface and a second transmission surface, allows most of the light emitted by the light-emitting diode to enter at least one layer of transmission medium at Brewster angle under the effects of total internal reflection and refraction, thereby helping to increase the energy density of the emitted light and thus increasing the brightness of the light illuminating the liquid crystal panel.

[0078] In some optional implementations of this embodiment, the angle between the cross-section of each point on the central reflective surface 10331 and the principal optical axis of the light-emitting diode 1032 is within a second preset angle range, so that the light emitted by the light-emitting diode 1032 onto the central reflective surface 10331 undergoes total internal reflection on the central reflective surface 10331, and is then reflected to the outer transmission surface 10332, refracted by the outer transmission surface, and incident on at least one layer of transmission medium 101 at Brewster angle.

[0079] The aforementioned second preset angle range is used to limit the tilt angle of the tangent at each point on the central reflective surface 10331, thereby limiting the incident angle of each ray of light illuminating the central reflective surface 10331, so that the incident angle is greater than the critical angle for total internal reflection. The tilt angle of the tangent at each point on the central reflective surface 10331 relative to the principal optical axis or emitting surface of the light-emitting diode 1032 can be limited by calculating the critical angle as shown in the above formula (2), so that total internal reflection occurs at any position on the central reflective surface 10331.

[0080] By setting the geometric features of the central reflective surface, total internal reflection of light can be achieved at the central reflective surface, which can more effectively limit the distribution of light and prevent light from being transmitted at the central reflective surface, thereby helping to further improve the energy density of the light emitted by the light-emitting unit.

[0081] In some optional implementations of this embodiment, a reflective coating is provided on the central reflective surface 10331. The reflective coating is used to reflect the light emitted to the central reflective surface 10331 to the outer transmissive surface 10332, and after being refracted by the outer transmissive surface 10332, it is incident on at least one transmissive medium 101 at Brewster angle.

[0082] Optionally, this embodiment can be combined with the above embodiments, that is, based on the fact that total internal reflection can occur on the first reflective surface, an emissive coating can be further added.

[0083] By setting a reflective coating on the central reflective surface, light can be further prevented from being transmitted from the central reflective surface, allowing the light-emitting unit to incident light at Brewster angle onto at least one layer of transmission medium with a higher energy density.

[0084] In some optional implementations of this embodiment, the back plate 102 is provided with a reflective coating for reflecting light reflected by at least one layer of the transmission medium 101 back to at least one layer of the transmission medium 101.

[0085] After light is reflected on the surface of at least one layer of transmissive medium, the reflected light is further reflected on the reflective coating on the back panel, thereby avoiding energy loss of light on the back panel and increasing the light intensity of light illuminating the LCD panel.

[0086] Figure 8 This is a schematic diagram of the structure of a display panel 800 provided in an embodiment of this application, as shown below. Figure 8 As shown, the display panel specifically includes: a liquid crystal panel 801 and a backlight module 100 described in the above embodiments, wherein the backlight module 100 emits linearly polarized light in the target polarization direction to the liquid crystal panel.

[0087] A polarizer 8011 can be disposed on the liquid crystal panel 801, and the polarizer 8011 can be disposed on two surfaces of the liquid crystal panel; after the linearly polarized light emitted by the backlight module 100 is incident on the polarizer 8011, it passes through the polarizer and is incident on the liquid crystal panel, wherein the polarization direction of the polarizer 8011 is parallel to the target polarization direction of the linearly polarized light of the backlight module 100.

[0088] According to the characteristics of polarizer 8011, light rays parallel to the polarization direction of the polarizer can pass through the polarizer without energy loss.

[0089] The display panel provided in this application embodiment, by applying the aforementioned backlight module, allows linearly polarized light incident on the liquid crystal panel to pass through the liquid crystal panel without loss, greatly improving the energy utilization rate of the backlight module.

[0090] Figure 9 This is a schematic diagram of the structure of a display device 900 provided in an embodiment of this application, as shown below. Figure 9 As shown, the display device includes the above-mentioned Figure 8 The illustrated embodiment describes a display panel 800. Furthermore, the display device 900 may also include a panel frame 901, a power module 902, and a data receiving module 903;

[0091] The display panel 800 is mounted on the panel frame 901.

[0092] The power supply terminal of the display panel 800 is connected to the power module 902, and the signal receiving terminal of the display panel 800 is connected to the data receiving module 903.

[0093] The power module 902 can provide the power required for the display panel 800 to operate, and the data receiving module 903 can receive input data. The display panel 800 drives the corresponding pixels to display the corresponding colors according to the received data.

[0094] In addition, the display device Figure 9 In addition to the components shown, it may also include a memory for storing data and programs, a processor for running applications, a data transfer bus, and various data interfaces (such as network interfaces and user interfaces).

[0095] The display device provided in this application embodiment can greatly improve the energy utilization rate of the backlight module and improve the display brightness by applying the above-mentioned display panel.

[0096] Those skilled in the art will further recognize that the units and algorithm steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, computer software, or a combination of both. To clearly illustrate the interchangeability of hardware and software, the components and steps of the various examples have been generally described in terms of functionality in the foregoing description. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different structures to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this application.

[0097] It should be understood that the terminology used herein is for the purpose of describing particular exemplary embodiments only and is not intended to be limiting. Unless the context clearly indicates otherwise, the singular forms “a,” “an,” and “described” as used herein may also mean including the plural forms. The terms “comprising,” “including,” “containing,” and “having” are inclusive and therefore indicate the presence of the stated features, steps, operations, elements, and / or components, but do not exclude the presence or addition of one or more other features, steps, operations, elements, components, and / or combinations thereof. The steps, processes, and operations described herein are not construed as requiring them to be performed in a particular order described or illustrated unless the order of performance is explicitly indicated. It should also be understood that additional or alternative steps may be used.

[0098] The above description is merely a specific embodiment of this application, enabling those skilled in the art to understand or implement this application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of this application. Therefore, this application is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features claimed herein.

Claims

1. A backlight module, characterized in that, include: The system comprises at least two layers of transmissive medium, a backplate, and a light-emitting module, wherein the light-emitting module is disposed on the backplate; wherein adjacent layers of transmissive medium are spaced apart by a predetermined distance by a support; the number of layers of transmissive medium is proportional to the content of linearly polarized light transmitted in a single positive direction; wherein the number of layers of at least two transmissive medium is three. The light emitted by the light-emitting module is incident on the at least two layers of transmission medium at Brewster angle, and after passing through the at least two layers of transmission medium, it is emitted as linearly polarized light in the target polarization direction. The light-emitting unit includes a light-emitting diode and a transparent colloid, wherein the transparent colloid is wrapped around the light-emitting diode; On each cross section containing the main optical axis of the light-emitting diode, for the light emitted by the light-emitting diode within a preset angle range, if the angle between the light ray and the main optical axis is the Brewster angle, then at the intersection of the light ray and the light-emitting surface of the transparent colloid, the cross section of the surface of the transparent colloid is perpendicular to the light ray. If the angle between the ray and the principal optical axis is not Brewster's angle, then at the intersection of the ray and the light-emitting surface of the transparent colloid, the tangent at the intersection is taken as the medium interface, and the ray is refracted at the medium interface, and incident on the at least one layer of transmission medium at Brewster's angle.

2. The backlight module according to claim 1, characterized in that, The light-emitting unit includes a light-emitting diode and a lens, with the lens covering the light-emitting diode; The lens includes a central reflecting surface and an outer transmitting surface, wherein the light emitted by the light-emitting diode onto the central reflecting surface is reflected onto the outer transmitting surface; For light reflected onto the outer transmission surface, at the intersection of the light ray and the outer transmission surface, with the tangent plane where the intersection point is located as the medium interface, the light ray is refracted at the medium interface and incident on the at least one layer of transmission medium at Brewster angle.

3. The backlight module according to claim 2, characterized in that, The outer transmissive surface includes a first transmissive surface and a second transmissive surface. The angle between the cross-section of each point on the first transmissive surface and the principal optical axis of the light-emitting diode is within a first preset angle range, so that the light emitted by the light-emitting diode onto the first transmissive surface undergoes total internal reflection on the first transmissive surface, and is then reflected onto the central reflective surface, and finally reflected back to the first transmissive surface by the central reflective surface. For light reflected onto the first transmission surface, at the intersection of the light and the first transmission surface, with the tangent plane where the intersection is located as the medium interface, the light is refracted at the medium interface and incident on the at least one layer of transmission medium at Brewster angle. For the light emitted by the light-emitting diode onto the second transmission surface, at the intersection of the light and the second transmission surface, with the tangent plane where the intersection is located as the medium interface, the light is refracted at the medium interface and incident on the at least one layer of transmission medium at Brewster angle.

4. The backlight module according to claim 2, characterized in that, The angle between the cross section of each point on the central reflective surface and the principal optical axis of the light-emitting diode is within a second preset angle range, so that the light emitted by the light-emitting diode onto the central reflective surface undergoes total internal reflection on the central reflective surface, and is then reflected onto the outer transmission surface, refracted by the outer transmission surface, and incident on the at least one layer of transmission medium at Brewster angle.

5. The backlight module according to claim 2, characterized in that, A reflective coating is provided on the central reflective surface. The reflective coating is used to reflect light emitted onto the central reflective surface to the outer transmissive surface, where it is refracted and incident on the at least one transmissive medium at a Brewster angle.

6. The backlight module according to claim 1, characterized in that, The support is a transparent adhesive strip, and each of the transmissive media is spaced a predetermined distance apart by the transparent adhesive strip.

7. The backlight module according to any one of claims 1-6, characterized in that, The back plate is provided with a reflective coating for reflecting the light reflected by the at least one layer of the transmission medium back to the at least one layer of the transmission medium.

8. A display panel, characterized in that, include: The liquid crystal panel and the backlight module according to any one of claims 1-7, wherein the backlight module emits linearly polarized light in the target polarization direction onto the liquid crystal panel.

9. A display device, characterized in that, include: The display panel as claimed in claim 8.

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