Direct-lit backlight modules and display devices

Abstract

This invention relates to the field of display technology, providing a direct-lit backlight module and display device. The direct-lit backlight module includes a backlight source and a lens. The backlight source has a light-emitting plane; the lens has an incident light surface and an exit light surface arranged opposite to each other, with the incident light surface closer to the backlight source than the exit light surface. Light emitted from the backlight source is refracted through the incident light surface into the lens and exits perpendicularly to the exit light surface. Users can view the data displayed on the display device at eye level, while others viewing the display device at an angle cannot receive the emitted light and therefore cannot view the displayed data. This solves the technical problem that existing direct-lit backlight modules cannot directly prevent peeping, thus eliminating the need for additional privacy films, improving the convenience of using the display device, and allowing users to securely view data through the display device.

Description

Technical Field

[0001] This invention relates to the field of display technology, and in particular to a direct-lit backlight module and display device. Background Technology

[0002] Display devices such as mobile phones, televisions, computers, and tablets require backlight modules to provide a light source. For example, a liquid crystal display (LCD) module consists of a liquid crystal cell placed in a parallel glass substrate, with TFTs (thin-film transistors) placed on the lower glass substrate. The rotation direction of liquid crystal molecules is controlled by changing the TFT signals and voltage, thereby controlling the display effect of the LCD module. The display effect of an LCD module largely depends on the backlight module.

[0003] Backlight modules can generally be divided into edge-lit backlight modules and direct-lit backlight modules. In edge-lit backlight modules, the light source is located on the side of the panel, and the light enters from the side. In direct-lit backlight modules, the light source is located on the back of the panel, and the light is emitted directly. Compared with edge-lit backlight modules, direct-lit backlight modules can give the display panel higher overall brightness and better display effect.

[0004] In today's information-saturated world, people are increasingly aware of the importance of protecting their personal information. Spying-proof electronic products are gaining popularity, with spy-proof mobile phones and monitors becoming bestsellers. Various spy-proof screen protectors are being widely used in display devices. Therefore, there is a pressing need in the market for a technical solution that achieves spy-proof functionality from the backlight module itself. Summary of the Invention

[0005] The purpose of this invention is to provide a direct-lit backlight module and display device, which aims to solve the technical problem that existing direct-lit backlight modules cannot directly prevent peeping.

[0006] In a first aspect, this application provides a direct-lit backlight module, the direct-lit backlight module comprising:

[0007] A backlight source having a light-emitting plane;

[0008] The lens has an incident light surface and an exit light surface that are disposed opposite to each other, wherein the incident light surface is closer to the backlight than the exit light surface;

[0009] The light emitted from the backlight is refracted by the incident light surface into the lens and emitted perpendicularly to the exit light plane.

[0010] In one embodiment, the angle between the light emitted by the backlight and the normal to the light-emitting plane is a first angle, the light-incident surface is a convex surface, the angle between the tangent of the convex surface and the light-emitting plane is a second angle, and the angle between the light-emitting plane and the light-emitting plane is a third angle. The second angle satisfies the following relationship:

[0011]

[0012] Where A is the angle of refraction, B is the angle of incidence, C is the first included angle, D is the second included angle, E is the third included angle, and n is the refractive index of the lens relative to the medium between the lens and the backlight.

[0013] In one embodiment, the angle between the light emitted by the backlight and the normal to the light-emitting plane is a first angle, the light-incident surface is a concave surface, the angle between the tangent of the concave surface and the light-emitting plane is a second angle, and the angle between the light-emitting plane and the light-emitting plane is a third angle. The second angle satisfies the following relationship:

[0014]

[0015] Where A is the angle of refraction, B is the angle of incidence, C is the first included angle, D is the second included angle, E is the third included angle, and n is the refractive index of the lens relative to the medium between the lens and the backlight.

[0016] In one embodiment, the light-emitting plane is parallel to the light-emitting plane.

[0017] In one embodiment, there is a gap between the lens and the light-incident surface, and the gap between the lens and the light-incident surface is filled with air, ammonia, Freon or carbon dioxide.

[0018] In one embodiment, the direct-lit backlight module further includes a protective plate connected to the lens, the protective plate being disposed around the light-incident surface and around the backlight source.

[0019] In one embodiment, the protective plate is a light-transmitting plate.

[0020] In one embodiment, the height of the protective plate is 5mm to 10mm.

[0021] In one embodiment, the protective plate is integrally formed with the lens.

[0022] In one embodiment, a support post is provided on the end face of the protective plate away from the lens.

[0023] In one embodiment, the support post is located in the end face portion of the protective plate away from the lens.

[0024] In one embodiment, the height of the support column is greater than the thickness of the backlight.

[0025] In one embodiment, there are multiple support columns, which are distributed at circumferential intervals along the protective plate.

[0026] In one embodiment, the backlight module further includes an optical film located on the side of the light-emitting plane away from the light-incident surface, and the optical film is mounted on the light-emitting plane through a light-transmitting column.

[0027] In one embodiment, one end of the light-transmitting column is in contact with the light-emitting plane, and the other end of the light-transmitting column is in contact with the optical film plane.

[0028] In one embodiment, the direct-lit backlight module further includes a circuit board, to which the backlight source is electrically connected and fixedly mounted.

[0029] Secondly, this application provides a display device, the display device including a display panel and a backlight module as described in any one of the above, the backlight module providing backlight for the display panel.

[0030] The beneficial effects of the direct-lit backlight module and display device provided by this invention are as follows: the light emitted by the backlight enters the lens through the light-incident surface and is refracted. The refracted incident light is perpendicular to the light-out plane and can exit the light-out plane without angular deflection. That is, the outgoing light after passing through the lens is perpendicular to the light-out plane, so that when the user looks straight at the light-out plane, they can receive the outgoing light and obtain the data information displayed by the display device. However, when others look at the display device at an angle, they cannot receive the outgoing light and cannot access the data information displayed by the display device. This solves the technical problem that existing direct-lit backlight modules cannot directly prevent peeping, so users do not need to apply an additional privacy film, improving the convenience of using the display device and enabling them to safely view data information through the display device. Attached Figure Description

[0031] To more clearly illustrate the technical solutions in the embodiments of the present invention, 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.

[0032] Figure 1 A cross-sectional view of a direct-lit backlight module provided in an embodiment of the present invention;

[0033] Figure 2 This is the optical path diagram of a direct-lit backlight module when the light-incident surface is a convex surface.

[0034] Figure 3 This is an optical path diagram of a direct-lit backlight module when the light-incident surface is a convex light-incident surface in another embodiment;

[0035] Figure 4 for Figure 3 A diagram showing the relationship between the first and second angles in the diagram;

[0036] Figure 5 for Figure 3 A schematic diagram of the operation of the direct-lit backlight module in the image;

[0037] Figure 6 This is the optical path diagram of a direct-lit backlight module when the light-incident surface is a concave surface.

[0038] Figure 7 This is a schematic diagram of a direct-lit backlight module in yet another embodiment;

[0039] Figure 8 This is a schematic diagram of a direct-lit backlight module in yet another embodiment;

[0040] Figure 9 This is a structural diagram of the lens, protective plate, and support column.

[0041] Figure 10 This is another view of the lens, protective plate, and support column;

[0042] Figure 11 This is a schematic diagram of the direct-lit backlight module in another embodiment.

[0043] The following are the labeling elements in the figure:

[0044] 100. Backlight; 101. Light-emitting surface;

[0045] 200. Lens; 210. Incident surface; 211. Refractive surface; 220. Exit surface;

[0046] 300. Circuit board;

[0047] 410. Protective plate; 420. Support column;

[0048] 500. Optical films;

[0049] 600, Light-transmitting column. Detailed Implementation

[0050] Embodiments of the present invention are described in detail below, examples of which are illustrated in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the present invention, and should not be construed as limiting the present invention.

[0051] Throughout this specification, references to "an embodiment" or "an embodiment" mean that a particular feature, structure, or characteristic described in connection with an embodiment is included in at least one embodiment of this application. Therefore, the phrases "in one embodiment" or "in some embodiments" appear in various places throughout the specification, and not all refer to the same embodiment. Furthermore, in one or more embodiments, particular features, structures, or characteristics may be combined in any suitable manner.

[0052] In the description of this invention, it should be understood that the terms "length", "width", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0053] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined with "first" or "second" may explicitly or implicitly include one or more of that feature.

[0054] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0055] Example 1

[0056] Figure 1 A cross-sectional view of a direct-lit backlight module provided in an embodiment of the present invention; Figure 2 The optical path diagram of a direct-lit backlight module when the light-incident surface 210 is a convex light-incident surface; Figure 6 The optical path diagram of a direct-lit backlight module when the light-incident surface 210 is a concave light-incident surface.

[0057] Combination Figure 1 , Figure 2 and Figure 6 This application provides a direct-lit backlight module, including a backlight 100 and a lens 200.

[0058] The backlight 100 has a light-emitting plane 101. Specifically, the light-emitting plane 101 refers to a plane perpendicular to the optical axis of the backlight 100. When the light-emitting surface of the backlight 100 is a plane, the normal to that plane is the optical axis, and that plane is the light-emitting plane 101. For example, the backlight 100 is a light-emitting sheet, such as a light-emitting chip, whose light-emitting surface is a plane. When the light-emitting surface of the backlight 100 is not a plane, such as when the backlight 100 is a point light source, a light-emitting diode, or a light bulb, the light emitted by the backlight 100 is symmetrically distributed about the optical axis, and the plane perpendicular to the optical axis is the light-emitting plane 101.

[0059] The optical axis is a virtual axis. Generally, the direction of the highest light intensity in the light emitted from the backlight 100 is the optical axis direction.

[0060] Optionally, the backlight 100 is a light-emitting chip. For example, the backlight 100 is an LED chip.

[0061] Specifically, in combination Figure 1 The direct-lit backlight module also includes a circuit board 300, to which the backlight 100 is electrically connected and fixedly mounted. The circuit board 300 is used for mounting and fixing the backlight 100, providing power to the backlight 100, and controlling the switching of the backlight 100.

[0062] Optionally, the circuit board 300 is a printed circuit board, and the backlight 100 is packaged on the circuit board 300, which achieves both electrical connection between the backlight 100 and the circuit board 300, and fixation of the backlight 100 on the circuit board 300. Figure 1 In one specific embodiment shown, the plane of the circuit board 300 for mounting the backlight 100 is parallel to the light-emitting plane 101.

[0063] It is understood that in other embodiments, the circuit board 300 may also be a discrete device circuit board, and the specific type of the circuit board 300 is not limited here.

[0064] In this embodiment, the lens 200 has an incident light surface 210 and an exit light surface 220 arranged opposite to each other. The incident light surface 210 is closer to the backlight 100 than the exit light surface 220. The light emitted by the backlight 100 is refracted by the incident light surface 210 and enters the lens 200 and exits perpendicular to the exit light surface 220.

[0065] Alternatively, the light-incident surface 210 can be a light-incident convex surface (see...). Figure 2That is, the convex direction of the light-incident surface 210 is away from the light-outceasing surface 220 and towards the backlight 100.

[0066] Alternatively, the light-incident surface 210 can be a light-incident concave surface (see...). Figure 6 That is, the convex direction of the light-incident surface 210 is towards the light-out surface 220 and away from the backlight 100.

[0067] Optionally, the incident surface 210 can be multiple refractive surfaces 211, and the refractive surfaces 211 can be refractive planes, refractive concave surfaces, refractive convex surfaces, or other shaped refractive surfaces 211. (Combined) Figure 7 Multiple refractive surfaces 211 are sequentially assembled. The refractive surface 211 facing the backlight 100 is closest to the light-emitting plane 101, while the refractive surfaces 211 on both sides are furthest from the light-emitting plane 101. The multiple refractive surfaces 211 are assembled into a general structure as shown in the figure. Figure 2 The incident light convex surface; or, combined with Figure 8 Multiple refractive planes are sequentially spliced ​​together. The refractive plane 211 facing the backlight 100 is the farthest from the light-emitting plane 101, while the refractive planes 211 on both sides are the closest to the light-emitting plane 101. The multiple refractive planes 211 are spliced ​​together to form a general structure as shown in the figure. Figure 6 The incident concave surface.

[0068] In this application, the light-incident surface 210 can be a single light-incident convex surface; a single light-incident concave surface; multiple refractive surfaces 211 sequentially spliced ​​together, wherein the refractive surface 211 can be a refractive plane, a refractive concave surface, a refractive convex surface or a refractive surface 211 of other shapes; a single light-incident surface 210 of other shapes; a combination of multiple light-incident surfaces 210 of different shapes; etc., without specific limitations.

[0069] Optionally, see Figure 1 The light-emitting plane 220 can be parallel to the light-emitting plane 101. Optionally, see [link to relevant documentation]. Figure 2 The light-emitting plane 220 may not be parallel to the light-emitting plane 101. For example, the angle between the light-emitting plane 220 and the light-emitting plane 101 may be -50° to 50°.

[0070] Specifically, the lens 200 also has an optical surface located between the light-emitting plane 220 and the light-incident plane 210 to guide the light rays refracted by the light-incident plane 210 into the lens 200, and then, after refraction or reflection by the optical surface, perpendicularly projecting onto the light-emitting plane 220. It can be understood that in other embodiments, combined with... Figure 1 The lens 200 does not have any other optical surfaces between the light-emitting plane 220 and the light-incident plane 210, so as to simplify the structure of the lens 200, facilitate production and manufacturing, and reduce manufacturing costs.

[0071] In this embodiment, the light emitted by the backlight 100 enters the lens 200 through the light-incident surface 210 and is refracted. The refracted incident light is perpendicular to the light-out surface 220 and can exit the light-out surface 220 without angular deflection. That is, the outgoing light after passing through the lens 200 is perpendicular to the light-out surface 220, so that when the user looks straight at the light-out surface 220, they can receive the outgoing light and view the data information displayed on the display device. However, when others look at the display device at an angle, they cannot receive the outgoing light and cannot view the data information displayed on the display device. This solves the technical problem that existing direct-lit backlight modules cannot directly prevent peeping, so users do not need to apply an additional privacy film, improving the convenience of using the display device and enabling them to safely view data information through the display device.

[0072] In one embodiment, combined Figure 2 The angle of refraction of the light emitted by the backlight 100 relative to the incident surface 210 is A, the angle of incidence is B, the angle between the light emitted by the backlight 100 and the normal of the emitting plane 101 is the first angle C, the incident surface 210 is an incident convex surface, the angle between the tangent of the incident convex surface and the emitting plane 101 is the second angle D, and the angle between the emitting plane 220 and the emitting plane 101 is the third angle E.

[0073] Since the sum of the interior angles of a triangle is 180°, we have the complementary angle of D + (C + 90°) + B = 180°; this can be simplified to equation (I):

[0074] B = C + D (Part 1)

[0075] According to the principle that vertical angles are equal, we can obtain B = X, and since X = A + (CE), it can be simplified to equation (I):

[0076] B = A + CE (II)

[0077] Given that the refractive index of lens 200 relative to the medium between lens 200 and backlight 100 is n, then

[0078]

[0079] Substituting equations (I) and (II) into equation (III), we obtain the second angle, which satisfies the following relationship:

[0080]

[0081] Where A is the angle of refraction, B is the angle of incidence, C is the first included angle, D is the second included angle, E is the third included angle, and n is the refractive index of lens 200 relative to the medium between lens 200 and backlight 100.

[0082] Thus, according to formula (iv), an entrance and exit convex surface can be designed to ensure that the light emitted by the backlight 100 enters the lens 200 through the entrance convex surface and is refracted. The refracted incident light is perpendicular to the exit plane 220, so that users who look straight at the exit plane 220 can receive the exit light, while others in other positions cannot receive the exit light, thus achieving the privacy function.

[0083] Specifically, when the light-emitting plane 101 is parallel to the light-emitting plane 220, such as Figure 3 As shown, if the third angle E is 0, then the second angle satisfies the following relationship:

[0084]

[0085] Thus, the light-emitting plane 101 is designed to be parallel to the light-emitting plane 220, which reduces the design difficulty of the light-incident convex surface and allows for the rapid design of the external dimensions of the lens 200.

[0086] Figure 4 This is the curve showing the correspondence between the first included angle C and the second included angle D. The first included angle C is obtained based on the position of the incident convex surface and the backlight 100. Figure 4 It can quickly find the corresponding second included angle D, thereby quickly designing the entrance and exit convex surfaces.

[0087] Figure 5 This is a schematic diagram of the operation of the direct-lit backlight module in the above embodiment. Since the light is emitted perpendicularly to the light-emitting plane 220, when the user is using it, their eyes are directly looking at the light-emitting plane 220, and their gaze is perpendicular to the light-emitting plane 220, so they can receive the emitted light. However, other people in other positions cannot receive the emitted light, thus achieving the privacy function.

[0088] In one embodiment, combined Figure 6 The angle of refraction of the light emitted by the backlight 100 relative to the incident surface 210 is A, the angle of incidence is B, the angle between the light emitted by the backlight 100 and the normal of the emitting plane 101 is the first angle C, the incident surface 210 is an incident concave surface, the angle between the tangent of the incident concave surface and the emitting plane 101 is the second angle D, and the angle between the emitting plane 220 and the emitting plane 101 is the third angle E.

[0089] Since the sum of the interior angles of a triangle is 180°, we can obtain the complementary angle of D + (B + 90°) + C = 180°, which can be simplified to equation (VI):

[0090] C = B + D (VI)

[0091] Based on the principle that vertical angles are equal, we can also obtain the above formula (II); substituting formulas (II) and (VI) into formula (III), we can obtain that the second angle satisfies the following relationship:

[0092]

[0093] Where A is the angle of refraction, B is the angle of incidence, C is the first included angle, D is the second included angle, E is the third included angle, and n is the refractive index of lens 200 relative to the medium between lens 200 and backlight 100.

[0094] Thus, according to formula (8), an entrance concave surface can be designed to ensure that the light emitted by the backlight 100 enters the lens 200 through the entrance concave surface and is refracted. The refracted incident light is perpendicular to the exit light plane 220, so that users looking at the exit light plane 220 can receive the exit light, while others in other positions cannot receive the exit light, thus achieving the privacy function.

[0095] Specifically, when the emitting plane 101 is parallel to the emitting plane 220, the third angle E is 0. Then, the second angle corresponding to the incident concave surface satisfies the following relationship:

[0096]

[0097] Thus, the light-emitting plane 101 is designed to be parallel to the light-emitting plane 220, which reduces the design difficulty of the light-incident convex surface and allows for the rapid design of the external dimensions of the lens 200.

[0098] In this application, the light-emitting plane 220 of the lens 200 is made into a plane, which can be easily matched with the plane of other optical devices, such as the optical film 500. If the light-emitting plane 220 is a convex surface, the distance between other optical devices and the convex surface is the distance between the convex surface and the outermost inflection point of the convex surface, which will increase the thickness of the backlight module. The light-incident surface 210 of the lens 200 is designed as a light-incident convex surface, a light-incident concave surface, multiple spliced ​​refractive surfaces 211, or other shapes of light-incident surface 210 for collimating light, to prevent the lens 200 from bulging towards the side away from the backlight 100, which helps to reduce the size of the lens 200, thereby reducing the distance between the backlight 100 and the light-incident surface 210 and reducing the thickness of the display device.

[0099] In this application, the gap between the light-incident surface 210 and the backlight 100 is used for heat dissipation to prevent the lens 200 from overheating and causing material deformation or fogging. The light-incident surface 210 can be a convex light-incident surface, a concave light-incident surface, multiple spliced ​​refractive surfaces 211, or other shapes of light-incident surface 210, which can increase the heat dissipation space between the light-incident surface 210 and the backlight 100 without increasing the gap between them to expand the heat dissipation space, which is beneficial for reducing the thickness of the backlight module.

[0100] In one embodiment, combined Figure 1There is a gap between lens 200 and light-incident surface 210, and the gap between lens 200 and light-incident surface 210 is filled with air, ammonia, Freon, or carbon dioxide. When the gap between lens 200 and light-incident surface 210 is filled with air, since the refractive index of air is 1, the refractive index of lens 200 relative to the medium between lens 200 and backlight 100 is the refractive index of lens 200, which helps to simplify the design requirements of the second angle D. When the gap between lens 200 and light-incident surface 210 is filled with ammonia, Freon, or carbon dioxide, since ammonia, Freon, or carbon dioxide has better heat dissipation, the gap between lens 200 and backlight 100 can be shortened, which helps to reduce the thickness of the backlight module and thus the thickness of the display device.

[0101] In one embodiment, combined Figure 1 , Figure 9 and Figure 10 The direct-lit backlight module also includes a protective plate 410 connected to the lens 200. The protective plate 410 is arranged around the light-incident surface 210 and around the backlight 100. The protective plate 410 can simultaneously protect the light-incident surface 210 and the backlight 100, preventing external interference with the optical path.

[0102] Optionally, the protective plate 410 is a light-transmitting plate, which facilitates observation of the working status of the backlight 100 from the side.

[0103] It is understood that in other embodiments, the protective plate 410 is opaque and can prevent external irrelevant light from entering the light-incident surface 210, while preventing the light from the backlight 100 from being emitted without passing through the light-incident surface 210. Therefore, the protective plate 410 can reduce noise and prevent light leakage from the backlight module.

[0104] Specifically, the height of the protection plate 410 is 5mm to 10mm, which can protect the backlight 100 located in the middle of the protection plate 410, and ensure that there is a suitable gap between the backlight 100 and the light-incident surface 210. This avoids the gap being too small, which would be detrimental to heat dissipation, and also avoids the gap being too large, which would result in the backlight module being too thick.

[0105] Optionally, the height of the protective plate 410 is 5mm, 6mm, 7mm, 8mm, 9mm or 10mm.

[0106] In this embodiment, the lens 200 is made of acrylic, glass, or other light-transmitting materials. The shape of the light-emitting plane 220 is polygonal, circular, elliptical, or irregular. When the light-emitting plane 220 is quadrilateral, its length is 15mm to 20mm, and its width is 15mm to 20mm. Optionally, the light-emitting plane 220 is square, and its side length is 15mm, 16mm, 17mm, 18mm, 19mm, or 20mm.

[0107] In one embodiment, the protective plate 410 and the lens 200 are integrally formed, thus eliminating the need for assembly between the protective plate 410 and the lens 200, and ensuring a firm connection that will not experience thermal fatigue at the connection point under long-term high-temperature conditions. Furthermore, the integral forming avoids the need for drilling, clamping, or pressing on the lens 200 when the protective plate 410 is assembled onto it, which could damage the lens 200.

[0108] It is understood that in other embodiments, the protective plate 410 and the lens 200 can be manufactured separately and then connected together by means of bonding, welding, snap-fitting, or screws. In this case, the material of the protective plate 410 and the lens 200 can be the same or different. For example, the protective plate 410 can be made of metal, such as copper, steel, or aluminum, which is beneficial for heat dissipation. When in contact with the circuit board 300, it can quickly conduct heat away, thereby reducing the gap between the light-incident surface 210 and the backlight 100 and thinning the backlight module.

[0109] In one embodiment, combined Figure 1 The end face of the protection plate 410 away from the lens 200 is provided with a support post 420, and the protection plate 410 is mounted through the support post 420, for example, mounted on the circuit board 300.

[0110] Specifically, the support column 420 is located in the end face portion of the protection plate 410 away from the lens 200, so that there is a gap between the end face portion of the protection plate 410 and the circuit board 300, which is conducive to heat dissipation and heat dissipation of the backlight module.

[0111] Specifically, the height of the support column 420 is greater than the thickness of the backlight 100, which helps to improve the protection of the backlight 100. It can be understood that in other embodiments, the height of the support column 420 is equal to or less than the thickness of the backlight 100.

[0112] Specifically, there are multiple support columns 420, which are distributed circumferentially around the protective plate 410 to improve the stability of the protective plate 410 and the lens 200. In the illustrated embodiment, there are four support columns 420 located at the four corners of the protective plate 410. It can be understood that in other embodiments, the number of support columns 420 may be three, five, or more.

[0113] Specifically, the height of the support column 420 is 0.5mm to 1.0mm, ensuring reasonable heat dissipation gap and support strength, without increasing the thickness of the backlight module.

[0114] For example, the height of the support column 420 is 0.5mm, 0.6mm, 0.7mm, 0.8mm, 0.9mm or 1.0mm.

[0115] In this embodiment, the support column 420, the protective plate 410 and the lens 200 are integrally formed, which reduces assembly operations, reduces damage to the protective plate 410 during assembly, and avoids thermal fatigue at the connection points during use.

[0116] It is understood that in other embodiments, the support column 420 and the protective plate 410 are manufactured separately, and the support column 420 is fixed to the protective plate 410 by means of bonding, snap-fitting or welding.

[0117] Combination Figure 11 In this embodiment, there can be multiple backlights 100, which are arranged at intervals. For example, the multiple backlights 100 are arranged in a row and column. The number of lenses 200 is the same as the number of backlights 100, and they correspond one-to-one, with each backlight 100 corresponding to one lens 200.

[0118] In one embodiment, combined Figure 11 The backlight module also includes an optical film 500, which is located on the side of the light-emitting plane 220 away from the light-incident plane 210. The optical film 500 is mounted on the light-emitting plane 220 through a light-transmitting column 600.

[0119] Compared to the optical film 500, which is mounted on the circuit board 300 between the backlight 100 using a support pillar, where the pillar is fixed to the circuit board 300 with clips or fasteners, potentially damaging the circuit board 300 and blocking light transmission, resulting in dark spots or abnormal optical quality on the display device, in this application, the optical film 500 is directly mounted on the light-emitting plane 220 via a light-transmitting pillar 600. This does not affect the light entering the optical film 500 through the light-emitting plane 220 and does not damage the circuit board 300.

[0120] Optionally, the optical film 500 includes a diffuser plate.

[0121] In one embodiment, one end of the light-transmitting column 600 contacts the light-emitting plane 220, and the other end of the light-transmitting column 600 contacts the plane of the optical film 500. Planar contact can increase the contact area, reduce contact stress, and avoid scratching the optical film 500.

[0122] It is understandable that the light-transmitting column 600 and the lens 200 are integrally molded to avoid the formation of assembly stress during the assembly process and to avoid damage to the lens 200.

[0123] Example 2

[0124] This application provides a display device, which includes a display panel and any one of the backlight modules in Embodiment 1 above, wherein the backlight module provides backlight for the display panel.

[0125] The display panel can be a TN (Twisted Nematic) display panel, an IPS (In-Plane Switching) display panel, a VA (Vertical Alignment) display panel, or an MVA (Multi-Domain Vertical Alignment) display panel; no specific limitation is made here.

[0126] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A direct backlight module, characterized in that: The direct type backlight module comprises: a backlight source having a light emitting plane; a lens having an opposite light entering surface and a light emitting plane, the light entering surface is closer to the backlight source than the light emitting plane; wherein the light emitted by the backlight source is refracted into the lens through the light entering surface and is emitted perpendicularly to the light emitting plane; the light emitting plane is not parallel to the light emitting plane; the angle between the light emitted by the backlight source and the normal line of the light emitting plane is a first angle, the light entering surface is a light entering convex surface, the tangent plane of the light entering convex surface and the light emitting plane forms a second angle, the light emitting plane and the light emitting plane forms a third angle, the second angle satisfies the following relationship: ； wherein C is the first angle, D is the second angle, E is the third angle, and n is the refractive index of the lens relative to the medium between the lens and the backlight source; or, the angle between the light emitted by the backlight source and the normal line of the light emitting plane is a first angle, the light entering surface is a light entering concave surface, the tangent plane of the light entering concave surface and the light emitting plane forms a second angle, the light emitting plane and the light emitting plane forms a third angle, the second angle satisfies the following relationship: ； wherein C is the first angle, D is the second angle, E is the third angle, and n is the refractive index of the lens relative to the medium between the lens and the backlight source.

2. The direct-lit backlight module of claim 1, wherein: The lens and the light entering surface have a gap, and the gap between the lens and the light entering surface is filled with air, ammonia, freon or carbon dioxide.

3. The direct-lit backlight module of claim 1, wherein: The direct type backlight module further comprises a protective plate connected to the lens, the protective plate is arranged around the light entering surface, and the protective plate is arranged around the backlight source.

4. The direct type backlight module according to claim 3, wherein: the protective plate is a light-transmitting plate; and / or, the height of the protective plate is 5mm-10mm; and / or, the protective plate is integrally formed with the lens; and / or, the end surface of the protective plate away from the lens is provided with a supporting column.

5. The direct-lit backlight module of claim 1, wherein: The backlight module further comprises an optical film, the optical film is located on the side of the light emitting plane away from the light entering surface, and the optical film is installed on the light emitting plane through a light-transmitting column.

6. The direct-lit backlight module according to claim 5, characterized in that: One end of the light-transmitting column is in plane contact with the light emitting plane, and the other end of the light-transmitting column is in plane contact with the optical film. 7.The direct-lit backlight module according to any one of claims 1 to 6, characterized in that: The direct type backlight module further comprises a circuit board, the backlight source is electrically connected to the circuit board and is fixedly installed on the circuit board.

8. A display device, characterized by: The display device comprises a display panel and a backlight module as claimed in any one of claims 1-7, and the backlight module provides backlight for the display panel.

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