Backlight module and display equipment

Abstract

The utility model relates to the technical field of backlight display, and provides a backlight module and display equipment, and the backlight module comprises a light-emitting unit which is provided with a light-emitting front surface; the first lens covers the light-emitting front surface; the scattering layer covers the first spherical lens; the second lens covers the scattering layer; the reflecting layer covers the middle part of the second spherical lens; and the third lens covers the reflecting layer. The first spherical lens is arranged on the light-emitting front face of an original backlight chip, the scattering layer is evaporated on the spherical lens, the second spherical lens is arranged on the scattering layer, the reflecting layer is arranged in the middle of the second spherical lens, and the third spherical lens is arranged outside the reflecting layer, so that the multi-diffusion effect is achieved, the center brightness is reduced, and meanwhile the brightness of the backlight chip is improved. According to the backlight module, the brightness of the periphery is improved, the light spots are more uniform, and the technical problems that in the prior art, the center brightness of the light spots emitted by the backlight module is high, the brightness of the periphery is low, and the brightness is not uniform are solved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of backlight display, more particularly to a backlight module and display device. BACKGROUND

[0002] Light emitting diode (LED) is a kind of semiconductor diode, which can convert electrical energy into light energy. LED has low working voltage, small working current, good impact resistance and shock resistance, high reliability, long service life, and can easily modulate the intensity of light emission by modulating the current intensity. LED backlight technology is a kind of backlight technology using light emitting diode (LED) as light source, which is widely used in lighting, display and other fields.

[0003] At present, the periphery of the backlight chip is usually provided with a scattering layer and a reflection layer, and a lens is provided to expand the angle of light emitted by the backlight chip to achieve the purpose of expanding the light spot and improving the illumination area. However, this scheme has the problem of uneven brightness of the light spot, with high brightness in the center of the light spot and low brightness around the light spot. CONTENT OF THE INVENTION

[0004] The purpose of the present application is to provide a backlight module and display device to solve the technical problem of uneven brightness of the light spot in the prior art, with high brightness in the center of the light spot and low brightness around the light spot.

[0005] Therefore, in a first aspect, the present application provides a backlight module, comprising: a light emitting unit having a light emitting front surface; a first lens covering the light emitting front surface; a scattering layer covering the first spherical lens; a second lens covering the scattering layer; a reflection layer covering the middle part of the second spherical lens; and a third lens covering the reflection layer.

[0006] The backlight module provided in the above-mentioned scheme has a first lens, a second lens and a third lens, all of which are spherical lenses.

[0007] The backlight module provided in the above-mentioned scheme has a third lens covering the second lens.

[0008] The backlight module provided in the above-mentioned scheme has a light emitting unit comprising: an LED chip; a lens layer covering around the LED chip; and a fluorescent layer covering the lens layer.

[0009] The backlight module provided in the above-mentioned scheme has an LED chip comprising a first LED chip and a second LED chip, and the light color emitted by the first LED chip is different from that emitted by the second LED chip.

[0010] The backlight module provided in the scheme has the advantages that the first LED chip emits blue light, the second LED chip emits green light, and the fluorescent layer comprises red fluorescent powder.

[0011] The backlight module provided in the scheme has the advantages that the outer surface of the lens layer is a curved surface with an arc line.

[0012] The backlight module provided in the scheme has the advantages that the curved surface comprises a first arc surface and a second arc surface, the first arc surface is connected with the second arc surface, and a concave valley structure is formed at the connection position.

[0013] The backlight module provided in the scheme has the advantages that the curved surface further comprises a first vertical surface and a second vertical surface, the first vertical surface is connected with the first arc surface, and the second vertical surface is connected with the second arc surface.

[0014] In the second aspect, the application provides a display device comprising the backlight module.

[0015] The backlight module and the display device provided in the application have the advantages that in the scheme, the first lens is arranged on the light-emitting front surface of the original backlight chip, the scattering layer is evaporated on the first lens, the second lens is arranged on the scattering layer, the reflection layer is arranged in the middle of the second lens, and the third lens is arranged outside the reflection layer. The multiple diffusion effect reduces the central brightness while improving the brightness around the center, and the light spot is more uniform. The technical problem that the light spot center has high brightness, the light spot around the center has low brightness, and the light spot brightness is uneven is solved. BRIEF DESCRIPTION OF DRAWINGS

[0016] In order to more clearly illustrate the technical solutions in the embodiments of the application, the following will briefly introduce the drawings needed to be used in the embodiments or the prior art description. Obviously, the drawings in the following description are only some embodiments of the application, and other drawings can be obtained by those skilled in the art without creative labor.

[0017] Figure 1 A cross-sectional structure schematic diagram of the backlight module provided in the embodiment of the application is shown in the figure.

[0018] Figure 2 A cross-sectional structure schematic diagram of the light-emitting unit provided in the embodiment of the application is shown in the figure.

[0019] Figure 3 Another cross-sectional structure schematic diagram of the light-emitting unit provided in the embodiment of the application is shown in the figure.

[0020] Figure 4 A schematic diagram of an outer shape structure of a lens layer is provided for an embodiment of the present application.

[0021] In the drawings, various reference numbers refer to components that perform the same or similar functions. In the following description, for the purposes of explanation, numerous specific details are set forth in order to provide a thorough understanding of the present application. It should be apparent, however, that the present application can be practiced in a wide variety of embodiments.

[0022] 1, light-emitting unit; 2, first lens; 3, scattering layer; 4, second lens; 5, reflecting layer; 6, third lens; 11, LED chip; 12, lens layer; 13, fluorescent layer; 111, first LED chip; 112, second LED chip; 121, first arc surface; 122, second arc surface; 123, concave valley structure; 124, first vertical surface; 125, second vertical surface. DETAILED DESCRIPTION

[0023] In order to make the technical problems to be solved, technical solutions and beneficial effects of the present application clearer, the present application will be further described in detail below in combination with the drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and not intended to limit the present application.

[0024] It should be noted that when a component is referred to as being "fixed to" or "set to" another component, it can be directly or indirectly on the other component. When a component is referred to as being "connected to" another component, it can be directly or indirectly connected to the other component. The terms "up", "down", "left", "right", "front", "back", "vertical", "horizontal", "top", "bottom", "inner", "outer", and the like indicate the orientation or position shown in the drawings, and are only for the convenience of description, and cannot be understood as a limitation on the technical solutions. The terms "first", "second" are only for the convenience of description, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features. The meaning of "a plurality of" is two or more, unless otherwise specifically limited.

[0025] CSP (Chip Scale Package) technology is an advanced semiconductor packaging technology that allows the packaged chip size to be close to or equal to the size of the bare chip, greatly reducing the volume of the package. CSP technology exhibits its unique advantages in many aspects. The development of CSP technology is of great significance to the progress of the semiconductor packaging industry, which not only improves the performance of electronic products, but also provides the possibility for designing smaller and more efficient electronic systems.

[0026] A light-emitting diode (LED) is a type of semiconductor diode that converts electrical energy into light energy. LEDs are characterized by low operating voltage, low operating current, good shock and vibration resistance, high reliability, and long lifespan. Furthermore, the intensity of light emitted can be easily modulated by varying the current flowing through them. LED backlighting technology is a backlighting technology that uses LEDs as the light source and is widely used in liquid crystal displays (LCDs) and television screens.

[0027] The increasing adoption of CSP packaging technology in LED display chips makes the size of the LED approach the size of the chip itself, which helps to achieve miniaturization of LED products.

[0028] Existing backlight chips typically have a scattering layer and a reflective layer around their periphery, along with a lens, to widen the angle of the light emitted by the backlight chip, thereby increasing the light spot size and illumination area. However, this approach results in uneven light spot brightness, with higher brightness at the center and lower brightness around the edges.

[0029] Therefore, embodiments of this application provide a backlight module, such as Figures 1-4 As shown, the backlight module includes: a light-emitting unit 1 with a front light-emitting surface; a first lens 2 covering the front light-emitting surface; a scattering layer 3 covering the first spherical lens; a second lens 4 covering the scattering layer 3; a reflective layer 5 covering the center of the second spherical lens; and a third lens 6 covering the reflective layer 5.

[0030] Specifically, in this embodiment, the backlight module includes a light-emitting unit 1, a scattering layer 3, a reflective layer 5, and a first lens 2, a second lens 4, and a third lens 6. The light-emitting unit 1 can be an LED chip 11, which has a light-emitting front side. Generally, the light-emitting front side is the light-emitting surface of the LED chip 11, facing away from the substrate. A first lens 2 covers the surface of the light-emitting front side, allowing light emitted from it to propagate outwards through the first lens 2. A scattering layer 3 also covers the surface of the first lens 2, scattering the light transmitted through the first lens 2 to increase the light divergence angle and thus increase the light spot formed by the light passing through the first lens 2. The scattering layer 3 can be deposited on the surface of the first lens 2 using a vapor deposition process.

[0031] A second lens 4 is also covered on the surface of the scattering layer 3, and light propagating through the scattering layer 3 is propagated outward through the second lens 4. A reflective layer 5 is covered at the center of the second lens 4. It should be noted that the reflective layer 5 does not completely cover the second lens 4, and the reflective layer 5 is located at the center of the second lens 4. In one example, the reflective layer 5 may be located at the geometric center of the second lens 4. The reflective layer 5 can be deposited on the surface of the second lens 4 using a vapor deposition process.

[0032] The surface of the scattering layer 3 is further covered by a third lens 6, and the light passing through the scattering layer 3 can be propagated outward through the third lens 6. The third lens 6 completely covers the scattering layer 3, and the third lens 6 can completely cover the second lens 4 or partially cover the second lens 4.

[0033] The first lens 2 can gaplessly cover the light-emitting front surface of the light-emitting unit 1. The first lens 2 can also gaplessly cover the entire light-emitting unit 1. Similarly, the second lens 4 can gaplessly cover the scattering layer 3, and the second lens 4 can also gaplessly cover the outer surface of the first lens 2; the third lens 6 gaplessly covers the reflecting layer 5, and the third lens 6 can gaplessly cover part of the outer surface of the second lens 4 or completely cover the outer surface of the second lens 4.

[0034] Compared with the prior art, the embodiment of the present application sets the first lens 2 on the original light-emitting front surface of the backlight chip, evaporates the scattering layer 3 on the first lens 2, sets the second lens 4 on the scattering layer 3, sets the reflecting layer 5 in the middle of the second lens 4, and sets the third lens 6 outside the reflecting layer 5. The effect of multiple diffusion reduces the central brightness while improving the brightness around, the light spot is more uniform, and the technical problem of the prior art that the scattering layer 3 and the reflecting layer 5 are usually set on the periphery of the backlight chip, and the lens is set to expand the angle of light emitted by the backlight chip to achieve the purpose of expanding the light spot and improving the illumination area is solved. However, this scheme has the technical problem that the central brightness of the light spot is high, the brightness around the light spot is low, and the brightness of the light spot is uneven.

[0035] In an embodiment, the first lens 2, the second lens 4, and the third lens 6 are all spherical lenses. The surface of the light-emitting front surface is covered by the spherical first lens 2, and the light emitted from the light-emitting front surface is propagated outward through the spherical first lens 2. The surface of the spherical first lens 2 is further covered by the scattering layer 3, and the scattering layer 3 can scatter the light transmitted by the spherical first lens 2 to increase the divergence angle of the light to increase the light spot formed by the light passing through the spherical first lens 2. The scattering layer 3 can be set on the surface of the spherical first lens 2 by an evaporation process.

[0036] The surface of the scattering layer 3 is further covered by the spherical second lens 4, and the light propagated through the scattering layer 3 is propagated outward through the spherical second lens 4. The middle position of the spherical second lens 4 is covered by the reflecting layer 5. It should be noted that the reflecting layer 5 does not completely cover the spherical second lens 4, and the reflecting layer 5 is set in the middle of the spherical second lens 4. In an example, the reflecting layer 5 can be set at the spherical center of the spherical second lens 4. The reflecting layer 5 can be set on the surface of the spherical second lens 4 by an evaporation process.

[0037] The surface of the scattering layer 3 is also covered by a spherical third lens 6, and the light passing through the scattering layer 3 can be propagated outward through the spherical third lens 6. The spherical third lens 6 completely covers the scattering layer 3. In addition, the spherical third lens 6 can completely cover the spherical second lens 4, or partially cover the spherical second lens 4.

[0038] The spherical first lens 2 can gaplessly cover the light-emitting front surface of the light-emitting unit 1. The spherical first lens 2 can also gaplessly cover the entire light-emitting unit 1. Similarly, the spherical second lens 4 can gaplessly cover the scattering layer 3, and the spherical second lens 4 can also gaplessly cover the outer surface of the spherical first lens 2; the spherical third lens 6 gaplessly covers the reflecting layer 5, wherein the spherical third lens 6 can gaplessly cover part of the outer surface of the spherical second lens 4, or completely cover the outer surface of the spherical second lens 4.

[0039] The use of spherical lenses can improve the diffusion effect of the light emitted by the light-emitting unit 1, making the diffusion area of the light larger and more uniform. The three light diffusion schemes of the first lens 2, the second lens 4, and the third lens 6 can improve the brightness of the lens edge. The combination of multiple lenses and the reflecting layer 5 arranged at the center of the second lens 4 reduces the brightness of the lens center and improves the brightness of the surrounding area, making the light spot more uniform.

[0040] In an embodiment, the third lens 6 covers the second lens 4. The third lens 6 can completely cover the second lens 4. This scheme can refract and reflect the light propagating through the second lens 4 again, avoiding the situation where the light not covered by the third lens 6 is directly propagated to the outside when the third lens 6 partially covers the second lens 4, thereby reducing the uniformity of the light. The third lens 6 that completely covers the second lens 4 can further increase the uniformity of light propagation.

[0041] In an embodiment, the backlight module can include but is not limited to the three-layer lens described above, such as four-layer lenses or more than four layers of lenses. The scattering layer 3 and the reflecting layer 5 can be arranged between the lenses according to actual needs. The purpose is to make the light spot more uniform through multiple layers of lenses.

[0042] In an embodiment, the light-emitting unit 1 includes: an LED chip 11. A lens layer 12 covering the LED chip 11. A fluorescent layer 13 covering the lens layer 12.

[0043] Specifically, in the embodiment, the LED chip 11 can be packaged by the CSP packaging technology. The shape of the lens layer 12 can be set reasonably according to the light diffusion effect. The lens layer 12 can be wrapped around the four sides of the LED chip 11 without gaps. The lens layer 12 can diffuse and propagate the light emitted by the LED chip 11. The fluorescent layer 13 is covered on the lens layer 12. That is, the fluorescent layer 13 is arranged on the surface of the lens layer 12, and the fluorescent layer 13 can completely cover the lens layer 12.

[0044] Part of the light emitted by the LED chip 11 is refracted and then emitted from the front of the LED chip 11 through the lens layer 12 and the fluorescent layer 13. Another part of the light is refracted back to the lens layer 12 by the fluorescent layer 13 and directly emitted from the side of the LED chip 11. Through multiple refraction and reflection, the light emitted by the LED chip 11 is uniformly diffused outward.

[0045] In an embodiment, a diffusion layer and a reflection layer 5 can also be arranged on the outer surface of the fluorescent layer 13. The diffusion layer is covered on the fluorescent layer 13, and the reflection layer 5 is covered on the diffusion layer. Part of the light emitted by the LED chip 11 is refracted and then emitted from the front of the LED chip 11 through the lens layer 12, the fluorescent layer 13, the diffusion layer, and the reflection layer 5. Another part of the light is refracted back to the lens layer 12 by the fluorescent layer 13, the diffusion layer, and the reflection layer 5 and directly emitted from the side of the LED chip 11. Through multiple refraction and reflection, the light emitted by the LED chip 11 is uniformly diffused outward.

[0046] In an embodiment, the LED chip 11 can include a first LED chip 111 and a second LED chip 112, and the first LED chip 111 and the second LED chip 112 emit light of different colors. In the embodiment, the first chip can emit blue light, and the second LED chip 112 can emit green light. The fluorescent layer 13 is coated with red fluorescent powder. Therefore, the LED chip 11 can emit white light after mixing the blue light, the green light, and the red fluorescent powder.

[0047] In an embodiment, the outer surface of the lens layer 12 is a curved surface with an arc line. The curved surface includes a first arc surface 121 and a second arc surface 122, and the first arc surface 121 is connected with the second arc surface 122 to form a concave valley structure 123 at the connection. In an embodiment, the curved surface further includes a first vertical surface 124 and a second vertical surface 125, the first vertical surface 124 is connected with the first arc surface 121, and the second vertical surface 125 is connected with the second arc surface 122.

[0048] Specifically, in the embodiment, the outer surface of the lens layer 12 includes a first arc surface 121 and a second arc surface 122, the first arc surface 121 and the second arc surface 122 can be integrally formed, and the surfaces of the two can be provided in a circular arc shape. Therefore, the first arc surface 121 and the second arc surface 122 are connected to form a concave valley structure 123, and the light emitting unit 1 is arranged inside the lens layer 12 and located at the middle position of the concave valley structure 123. The lens layer 12 forms two convex lens structures on both sides of the light emitting unit 1, so that the beam angle of the light emitting unit 1 can be further opened through the first arc surface 121 and the second arc surface 122, and the backlight module has a larger light emitting angle.

[0049] In addition, the embodiment of the present application further provides a display device, which comprises the backlight module as described above.

[0050] Specifically, in the embodiment, the display device can comprise a housing and the backlight module as described above, and the backlight module is fixedly arranged on the housing. The backlight module comprises the light emitting unit 1 having a light emitting front surface, the first lens 2 covering the light emitting front surface, the scattering layer 3 covering the first spherical lens, the second lens 4 covering the scattering layer 3, the reflecting layer 5 covering the middle part of the second spherical lens, and the third lens 6 covering the reflecting layer 5.

[0051] The backlight module comprises the light emitting unit 1, the scattering layer 3, the reflecting layer 5, and the first lens 2, the second lens 4 and the third lens 6. The light emitting unit 1 can be an LED chip 11, and the LED chip 11 has a light emitting front surface. Generally, the light emitting front surface is the light emitting surface of the LED chip 11, and the light emitting front surface faces away from the substrate. The first lens 2 covers the surface of the light emitting front surface, and the light emitted from the light emitting front surface is transmitted outward through the first lens 2. The scattering layer 3 covers the surface of the first lens 2, and the scattering layer 3 can scatter the light transmitted by the first lens 2 to increase the divergence angle of the light, so as to increase the light spot formed by the first lens 2. The scattering layer 3 can be arranged on the surface of the first lens 2 by a vapor deposition process.

[0052] The second lens 4 covers the surface of the scattering layer 3, and the light transmitted by the scattering layer 3 is transmitted outward through the second lens 4. The reflecting layer 5 covers the middle part of the second lens 4. It should be noted that the reflecting layer 5 does not completely cover the second lens 4, and the reflecting layer 5 is arranged at the middle part of the second lens 4. In an example, the reflecting layer 5 can be arranged at the geometric center of the second lens 4. The reflecting layer 5 can be arranged on the surface of the second lens 4 by a vapor deposition process.

[0053] The third lens 6 covers the surface of the scattering layer 3, and the light transmitted by the scattering layer 3 can be transmitted outward through the third lens 6. The third lens 6 completely covers the scattering layer 3, and in addition, the third lens 6 can completely cover the second lens 4 or partially cover the second lens 4.

[0054] The first lens 2 can be gaplessly coated on the light emitting front surface of the light emitting unit 1. The first lens 2 can also be gaplessly coated on the entire light emitting unit 1. Similarly, the second lens 4 can be gaplessly coated on the scattering layer 3, and the second lens 4 can also be gaplessly coated on the outer surface of the first lens 2; the third lens 6 is gaplessly coated on the reflecting layer 5, wherein the third lens 6 can be gaplessly coated on part of the outer surface of the second lens 4, or can be gaplessly completely coated on the outer surface of the second lens 4.

[0055] The first lens 2, the second lens 4, and the third lens 6 can be spherical lenses. The surface of the light emitting front surface is covered by the spherical first lens 2, and the light emitted from the light emitting front surface is transmitted outward through the spherical first lens 2. The surface of the spherical first lens 2 is further covered by the scattering layer 3, and the scattering layer 3 can scatter the light transmitted by the spherical first lens 2, increase the divergence angle of the light, and increase the light spot formed by the light passing through the spherical first lens 2. The scattering layer 3 can be set on the surface of the spherical first lens 2 by a vapor deposition process.

[0056] The surface of the scattering layer 3 is further covered by the spherical second lens 4, and the light transmitted through the scattering layer 3 is transmitted outward through the spherical second lens 4. The middle part of the spherical second lens 4 is covered by the reflecting layer 5, and it is necessary to note that the reflecting layer 5 does not completely cover the spherical second lens 4, and the reflecting layer 5 is set in the middle part of the spherical second lens 4. In one example, the reflecting layer 5 can be set at the spherical center of the spherical second lens 4. The reflecting layer 5 can be set on the surface of the spherical second lens 4 by a vapor deposition process.

[0057] The surface of the scattering layer 3 is further covered by the spherical third lens 6, and the light transmitted through the scattering layer 3 can be transmitted outward through the spherical third lens 6. The spherical third lens 6 completely covers the scattering layer 3, and in addition, the spherical third lens 6 can completely cover the spherical second lens 4, or can partially cover the spherical second lens 4.

[0058] The spherical first lens 2 can be gaplessly coated on the light emitting front surface of the light emitting unit 1. The spherical first lens 2 can also be gaplessly coated on the entire light emitting unit 1. Similarly, the spherical second lens 4 can be gaplessly coated on the scattering layer 3, and the spherical second lens 4 can also be gaplessly coated on the outer surface of the spherical first lens 2; the spherical third lens 6 is gaplessly coated on the reflecting layer 5, wherein the spherical third lens 6 can be gaplessly coated on part of the outer surface of the spherical second lens 4, or can be gaplessly completely coated on the outer surface of the spherical second lens 4.

[0059] The spherical lens can improve the diffusion effect of the light emitted by the light emitting unit 1, so that the diffusion area of the light is larger and more uniform. The three light diffusion schemes of the first lens 2, the second lens 4 and the third lens 6 can improve the brightness of the lens edge. The multiple lenses combined with the reflective layer 5 arranged at the center of the second lens 4 reduce the brightness of the lens center and improve the brightness of the surrounding, and the light spot is more uniform.

[0060] The third lens 6 can cover the second lens 4. The third lens 6 can be completely covered around the second lens 4. This scheme can refract and reflect the light propagating through the second lens 4 again, avoiding the light not covered by the third lens 6 being directly propagated to the outside when the third lens 6 partially covers the second lens 4, thereby reducing the uniformity of the light. The third lens 6 completely covering the second lens 4 can further increase the uniformity of light propagation.

[0061] The light emitting unit 1 includes: an LED chip 11. A lens layer 12 covering the LED chip 11. A fluorescent layer 13 covering the lens layer 12. The LED chip 11 can be packaged by the CSP packaging technology. The shape of the lens layer 12 can be reasonably set according to the light diffusion effect. The lens layer 12 can cover the four sides of the LED chip 11 without gaps. The lens layer 12 can diffuse and propagate the light emitted by the LED chip 11. The fluorescent layer 13 covers the lens layer 12. That is, the fluorescent layer 13 is arranged on the surface of the lens layer 12, and the fluorescent layer 13 can completely cover the lens layer 12.

[0062] Part of the light emitted by the LED chip 11 is refracted and emitted in turn through the lens layer 12 and the fluorescent layer 13; and another part of the light is refracted back to the lens layer 12 by the fluorescent layer 13 and directly emitted from the side of the LED chip 11. After multiple refraction and reflection, the light emitted by the LED chip 11 is uniformly diffused outward.

[0063] The LED chip 11 can include a first LED chip 111 and a second LED chip 112, and the first LED chip 111 and the second LED chip 112 emit light of different colors. In this embodiment, the first chip can emit blue light, and the second LED chip 112 can emit green light. The fluorescent layer 13 is coated with red fluorescent powder. Therefore, the LED chip 11 can emit white light after mixing blue light, green light and red fluorescent powder.

[0064] The outer surface of the lens layer 12 comprises a first arc surface 121 and a second arc surface 122, which can be integrally formed and have a circular arc shape, and the first arc surface 121 and the second arc surface 122 are connected to form a concave valley structure 123, and the light emitting unit 1 is arranged inside the lens layer 12 and located at the middle position of the concave valley structure 123. The lens layer 12 forms two convex lens structures on both sides of the light emitting unit 1, so that the beam angle of the light emitting unit 1 can be further opened through the first arc surface 121 and the second arc surface 122, and the backlight module has a larger light emitting angle.

[0065] The display device provided by the embodiment of the present application sets a first lens 2 on the original light emitting front surface of the backlight chip, evaporates a scattering layer 3 on the first lens 2, sets a second lens 4 on the scattering layer 3, sets a reflecting layer 5 in the middle of the second lens 4, sets a third lens 6 outside the reflecting layer 5, and has the effect of multiple diffusion, reduces the central brightness, improves the brightness around, and makes the light spot more uniform, thereby solving the technical problem that in the prior art, the scattering layer 3 and the reflecting layer 5 are usually arranged on the periphery of the backlight chip, and the lens is arranged to expand the angle of the light emitted by the backlight chip, so as to achieve the purpose of expanding the light spot and improving the light area. However, this scheme has the technical problem that the central brightness of the light spot is high, the brightness around the light spot is low, and the brightness of the light spot is uneven.

[0066] The above only describes the preferred embodiments of the present application and is not used to limit the present application, and any modification, equivalent replacement and improvement made within the spirit and principle of the present application should be included in the protection scope of the present application.

Claims

1. A backlight module, characterized in that, The backlight module comprises: a light emitting unit having a light emitting surface; a first lens covering the light emitting surface; a scattering layer covering the first lens; a second lens covering the scattering layer; a reflecting layer covering a middle part of the second lens; a third lens covering the reflecting layer.

2. The backlight module of claim 1, wherein, The first lens, the second lens and the third lens are all spherical lenses.

3. The backlight module of claim 1, wherein, The third lens covers the second lens.

4. The backlight module of claim 1, wherein, The light emitting unit comprises: an LED chip; a lens layer covering around the LED chip; a fluorescent layer covering the lens layer.

5. The backlight module of claim 4, wherein, The LED chip comprises a first LED chip and a second LED chip, and the first LED chip and the second LED chip emit light of different colors.

6. The backlight module of claim 5, wherein, The first LED chip emits blue light, the second LED chip emits green light, and the fluorescent layer comprises red fluorescent powder.

7. The backlight module of claim 6, wherein, An outer surface of the lens layer is a curved surface with an arc line.

8. The backlight module of claim 7, wherein, The curved surface comprises a first arc surface and a second arc surface, the first arc surface is connected with the second arc surface, and a concave valley structure is formed at the connection.

9. The backlight module of claim 8, wherein, The curved surface further comprises a first vertical surface and a second vertical surface, the first vertical surface is connected with the first arc surface, and the second vertical surface is connected with the second arc surface.

10. A display device, characterized by comprising: The backlight module as claimed in any one of claims 1-9.

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