Backlight liquid crystal display module based on mini-LED

Abstract

The invention discloses a mini-LED-based backlight liquid crystal display module in the technical field of backlight displays, which comprises a plurality of LED lamps in a normal mode and a plurality of night vision compatible LED lamps, and the two kinds of LED lamps are respectively and uniformly distributed at intervals; the night vision compatible LED lamp comprises a support, an LED lamp source and a glue layer, the LED lamp source is arranged in a groove of the support, and the glue layer covers the surface of the LED lamp source for packaging. The glue layer is formed by mixing packaging glue and a composite color filtering material, and the composite color filtering material is used for absorbing radiation in the wave band of 610-930 nm. According to the backlight liquid crystal display module, full-color display can be achieved in a night vision compatible mode, meanwhile, the complexity of a driving circuit can be greatly reduced, the light leakage problem does not exist, the good night vision compatible effect can be achieved, the packaging difficulty and complexity are reduced, and the yield is increased.

Description

Technical Field

[0001] The present invention relates to the technical field of backlight displays, and in particular to a backlight liquid crystal display module based on mini-LED. Background Art

[0002] With the development of display technology, the liquid crystal display technology based on mini-LED backlight has become a key technology that major display companies are competing to layout. It has many advantages such as high contrast ratio, high color reproducibility, and low power consumption, and thus has received extensive attention and application. The night vision compatibility of a liquid crystal display module refers to reducing the radiation of light-emitting devices such as in-cabin lighting and information display in the near-infrared band (610nm - 930nm), reducing the night vision radiance in the cabin, and reducing the interference to the night vision imaging system.

[0003] Currently, the liquid crystal display module mainly adopts the dual-mode backlight module technology to achieve the night vision compatibility function. In the night vision compatibility mode, orange-green-blue (OGB) three-color LED lights are used as the backlight source. As shown in Figure 1 , the OGB three-color LED lights (2) are composite LED lights composed of orange, blue, and green light-emitting chips with wavelengths in the range of 590nm - 610nm, which can effectively reduce the radiation in the near-infrared band in the backlight, thereby achieving the night vision compatibility function of the display module. In the daytime mode, normal-mode LED lights (1) with high luminous efficiency white light are used as the backlight source, and higher display brightness can be achieved with lower power consumption. Currently, the backlight module in the liquid crystal display technology based on mini-LED backlight adopts precise zone dimming, which can independently control the on and off of the backlight source in each zone, making its driving circuit more complex. Especially at present, the number of zones in mini-LED backlight liquid crystal display products increases, which means that the number of its driving ICs and LED lights also increases significantly.

[0004] If the liquid crystal display technology based on mini-LED backlight adopts the current mainstream dual-mode backlight source technology to achieve the night vision compatibility function, the corresponding OGB three-color LED lights will require three sets of corresponding mini-LED backlight driving circuits at the same time, which will lead to a very complex driving circuit and an overly large driving circuit scale, making it difficult to carry out engineering applications. Summary of the Invention

[0005] By providing a backlight liquid crystal display module based on mini-LED, the present application solves the problem that the backlight liquid crystal display driving circuit in the prior art is complex and difficult to be applied in engineering, thereby greatly simplifying the mini-LED backlight driving circuit in the night vision compatibility mode, and realizing the engineering application of the mini-LED night vision compatibility function.

[0006] An embodiment of the present application provides a backlight liquid crystal display module based on mini-LEDs, including: a plurality of LED lights in normal mode and a plurality of night vision compatible LED lights mounted on a printed circuit board, and the two types of LED lights are evenly spaced apart; the night vision compatible LED light includes a bracket, an LED light source, and a glue layer, the LED light source is arranged in the bracket groove, and the glue layer covers the surface of the LED light source for encapsulation; the glue layer is composed of an encapsulation glue and a composite color filter material, and the composite color filter material is used to absorb radiation in the wavelength band of 610-930 nm.

[0007] The beneficial effects of the above embodiment are as follows: In the night vision compatible mode, the backlight liquid crystal display module adopts a single LED light source to replace the single-color or multi-color LED mixed light as the backlight source, which can achieve full-color display in the night vision compatible mode and greatly reduce the complexity of the driving circuit. In addition, in the traditional liquid crystal display module, the light filter film is pasted on the surface of the LED device, which will cause edge light leakage problems, it is difficult to completely cover the original LED light, and secondary encapsulation is required, which increases the encapsulation process, and also puts higher requirements on the encapsulation flatness of the LED surface, increasing the difficulty and complexity of encapsulation and reducing the yield; while in this backlight liquid crystal display module, the new composite color filter material is doped into the LED encapsulation glue, and after being completely dissolved and mixed with the glue, it is integrally encapsulated, there is no light leakage problem, a good night vision compatible effect can be obtained, and the LED encapsulation process is not increased, reducing the difficulty and complexity of encapsulation and improving the yield.

[0008] Based on the above embodiment, the present application can be further improved as follows: In one embodiment of the present application, the night vision compatible LED lights are driven in a zoned dimming manner. The brightness of each zone can be controlled separately.

[0009] In one embodiment of the present application, the composite color filter material includes infrared absorption dye A and infrared absorption dye B, and the maximum central absorption wavelength of the infrared absorption dye A is 710±5 nm; the maximum central absorption wavelength of the infrared absorption dye B is 860±5 nm. The infrared absorption dye A has a strong absorption capacity for radiation in the wavelength band of 600 nm to 770 nm, and the infrared absorption dye B has a strong absorption capacity for radiation in the wavelength band of 720 nm to 950 nm. The composite color filter material has a strong absorption capacity for radiation in the wavelength band of 610-930 nm, meeting the absorption range of the wavelength band for night vision compatibility.

[0010] In one embodiment of the present application, the infrared absorption dye A adopts a copper phthalocyanine derivative or a carbon nanotube composite dye, and the infrared absorption dye B adopts a nickel dithiolene complex or a graphene-based dye.

[0011] In one embodiment of the present application, the encapsulation glue is a modified epoxy resin glue, which can be fully mixed and dissolved with infrared absorption dye A and infrared absorption dye B.

[0012] In one embodiment of the present application, the method for preparing the glue layer is as follows: Mix infrared absorption dye A, infrared absorption dye B with the encapsulation glue, and then use a centrifugal stirrer to fully mix them through three-stage gradient centrifugation to ensure that the two dyes fully exert their infrared absorption efficiency and form a composite color filter material.

[0013] In one embodiment of the present application, the LED light source includes a blue light LED emitting chip and a fluorescent film, and the fluorescent film is pasted on the surface of the blue light LED emitting chip. A white light fluorescent film is pasted on the surface of the LED blue light emitting chip, and at the same time, the above composite color filter material is used for encapsulation to make a white light LED lamp that meets the requirements of night vision compatibility. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following will briefly introduce the drawings required for the description of the specific embodiments or the prior art. In all the drawings, similar elements or parts are generally identified by similar reference numerals. In the drawings, the elements or parts are not necessarily drawn to scale.

[0015] Figure 1 It is a schematic diagram of the dual-mode backlight lamp bead arrangement of an existing night vision compatible liquid crystal display module; Figure 2 It is a schematic diagram of the dual-mode backlight arrangement of the mini-LED-based backlight liquid crystal display module in this embodiment; Figure 3 It is a spectral absorption curve diagram of infrared absorption dye A in this embodiment; Figure 4 It is a spectral absorption curve diagram of infrared absorption dye B in this embodiment; Figure 5 It is a spectral absorption curve diagram of the composite color filter material in this embodiment; Figure 6 It is a schematic structural diagram of the LED light source in this embodiment.

[0016] Among them, 1. LED lamp in normal mode, 2. OGB three-color LED lamp, 3. LED lamp compatible with night vision, 4. bracket, 5. glue layer, 6. blue light LED emitting chip, 7. fluorescent film. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0017] In combination with the specific embodiments, the present invention will be further clarified. It should be understood that these embodiments are only used to illustrate the present invention and not to limit the scope of the present invention. After reading the present invention, various equivalent forms of modification of the present invention by those skilled in the art all fall within the scope defined by the appended claims of this application.

[0018] It should be noted that like reference numerals and letters denote like items in the following figures. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0019] In the description of the present invention, it should be noted that unless otherwise clearly specified and limited, the terms "set", "installed", "connected", and "connected" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances. In addition, the parts not involved in the present invention are the same as the prior art or can be implemented by using the prior art.

[0020] In the description of the present invention, the schematic expressions of the above terms do not necessarily refer to the same embodiments or examples. Moreover, the specific features, structures, materials, or characteristics described can be combined in a suitable manner in any one or more embodiments or examples. In addition, without contradiction, those skilled in the art can combine and combine the different embodiments or examples described in the present invention and the features of different embodiments or examples.

[0021] By providing a backlight liquid crystal display module based on mini-LED in the embodiments of the present application, the problems in the prior art that the backlight liquid crystal display driving circuit is complex and difficult to be applied in engineering are solved, thereby greatly simplifying the effect of the mini-LED backlight driving circuit in the night vision compatible mode, and realizing the engineering application of the mini-LED night vision compatible function.

[0022] The technical solutions in the embodiments of the present application for solving the above problems are generally as follows: Embodiment 1: As Figure 2As shown in the figure, a mini-LED-based backlight liquid crystal display module includes: a plurality of normal-mode LED lights (1) and a plurality of night-vision compatible LED lights (3) mounted on a printed circuit board, and the two types of LED lights are evenly spaced apart; the night-vision compatible LED lights (3) include a bracket (4), an LED light source, and an adhesive layer (5). The LED light source is arranged in the groove of the bracket (4), and the adhesive layer (5) covers the surface of the LED light source for encapsulation; the adhesive layer (5) is composed of a packaging adhesive and a composite color filter material, and the composite color filter material is used to absorb radiation in the wavelength band of 610-930 nm.

[0023] Among them, the composite color filter material includes infrared absorption dye A and infrared absorption dye B. The maximum central absorption wavelength of infrared absorption dye A is 710±5 nm, and the effective absorption band is 600-770 nm. Its minimum effective absorption wavelength ≤610 nm, and its spectral absorption curve is as Figure 3 shown; the maximum central absorption wavelength of infrared absorption dye B is 860±5 nm, and the effective absorption band is 720-950 nm. Its minimum effective absorption wavelength ≤770 nm, and its maximum effective absorption wavelength ≥930 nm. Its spectral absorption curve is as Figure 4 shown. The spectral absorption curve of the composite color filter material is as Figure 5 shown, and it has a strong absorption capacity for radiation in the wavelength band of 610-930 nm, meeting the band absorption range for night-vision compatibility.

[0024] Among them, infrared absorption dye A can be a copper phthalocyanine derivative or a carbon nanotube composite dye, and infrared absorption dye B can be a nickel dithiolene complex or a graphene-based dye. The packaging adhesive can be a modified epoxy resin adhesive, which can be fully mixed and dissolved with infrared absorption dye A and infrared absorption dye B.

[0025] Among them, the preparation method of the adhesive layer (5) is as follows: Take infrared absorption dye A, infrared absorption dye B and the packaging adhesive in an appropriate ratio (such as 7:3) and mix them. Use a centrifugal stirrer to perform three-stage gradient centrifugation (500→2000→5000 rpm) to ensure full and uniform mixing. Three-stage gradient centrifugation: Low-speed centrifugation (500 rpm) initially disperses the dyes; medium-speed centrifugation (2000 rpm) breaks the air bubbles; high-speed centrifugation (5000 rpm) achieves molecular-level uniform mixing. Through this process, the dispersion uniformity of the dyes is improved, avoiding fluctuations in light transmittance caused by excessive local concentration, and ensuring that the two dyes fully exert their infrared absorption efficiency to produce the composite color filter material.

[0026] Among them, as Figure 6As shown, the LED light source meeting the night vision compatibility requirements includes a blue light LED light emitting chip (6) and a fluorescent film (7), wherein the fluorescent film (7) is adhered to the surface of the blue light LED light emitting chip (6). A white light fluorescent film (7) is adhered to the surface of the LED blue light emitting chip, and the above-mentioned composite color filter material is used for packaging to produce a white light LED lamp meeting the night vision compatibility requirements.

[0027] Furthermore, the driving mode of the night vision compatible LED lamp (3) is mini-LED partition dimming control, and the brightness of the night vision compatible LED lamp (3) in each partition can be controlled individually.

[0028] The working process of the above embodiment is as follows: the backlight LCD display module has two backlight systems, corresponding to the night vision compatible mode and the non-night vision compatible mode respectively. In the night vision compatible mode, the night vision compatible LED backlight source is turned on, and the composite color filter material absorbs the radiation of the specific band of the LED light source to ensure that the mini-LED display meets the night vision compatibility requirements; in the non-night vision compatible mode, the night vision compatible LED backlight source is turned off and the normal mode LED light is turned on, which can achieve higher display brightness with lower power consumption and ensure the normal display effect of the display.

[0029] The technical solutions in the above embodiments of the present application have at least the following technical effects or advantages: 1. Existing technology requires independent driver circuits for each of the three OGB LED colors (one driver IC for each color), resulting in exponentially increased circuit complexity as the number of mini-LED zones increases. This backlit LCD module uses a single white LED light source, requiring only a single driver circuit. Combined with zone dimming technology, this significantly reduces the number of driver circuits by 66% and power consumption by 30%.

[0030] 2. In existing technologies, the filter film requires a secondary bonding or lamination process after LED packaging. This not only increases the packaging process steps (such as surface treatment, precise alignment, and lamination), but also places stringent requirements on package flatness. However, this backlit LCD display module directly incorporates the composite color filter material into the LED packaging glue, achieving uniform mixing through centrifugal agitation. The packaging glue and color filter material are then integrated into a single mold. This process eliminates the separate processing step for the filter film, simplifies the production process, reduces equipment investment, and avoids packaging defects (such as bubbles and warping) caused by poor filter film bonding, significantly improving production efficiency and yield.

[0031] 3. Existing filter films, due to physical bonding, can cause gaps or light leakage around edges (especially in tiny mini-LED packaging units), resulting in insufficient near-infrared radiation suppression. This invention achieves seamless coverage of the filter layer and the light-emitting chip through molecular-level fusion of the color filter material and the packaging adhesive, resulting in more uniform absorption band coverage.

[0032] Example 2: Based on the backlight liquid crystal display module shown in Example 1, the following further improvements are made: Optionally, graphene heat dissipation particles (with a proportion ≤ 0.5%) are incorporated into the composite color filter material (5) to enhance the lateral heat diffusion ability and avoid the attenuation of material properties caused by local high temperature.

[0033] Optionally, a refractive index gradient layer (such as a SiO2-TiO2 composite layer) is added between the fluorescent film (6) and the composite color filter material (5) to improve the conversion efficiency from blue light (450 nm) to white light and reduce light loss.

[0034] Optionally, aluminum nitride heat conduction columns are embedded at the bottom of the blue LED chip (7) to form a vertical heat dissipation channel with the copper substrate of the packaging bracket (4), reduce the junction temperature, and extend the life of the LED.

[0035] Although the embodiments of the present invention have been shown and described above, it can be understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those of ordinary skill in the art can make changes, modifications, substitutions, and variations to the above embodiments within the scope of the present invention.

Claims

1. A mini-LED-based backlight liquid crystal display module, characterized in that, Including: A plurality of LED lights in normal mode and a plurality of night vision compatible LED lights, and the two types of LED lights are evenly spaced apart respectively; The night vision compatible LED light includes a bracket, an LED light source, and a glue layer. The LED light source is arranged in the groove of the bracket, and the glue layer covers the surface of the LED light source for encapsulation; the glue layer is composed of a mixed encapsulation glue and a composite color filter material, and the composite color filter material is used to absorb radiation in the wavelength band of 610 - 930 nm.

2. The backlight liquid crystal display module according to claim 1, wherein: The composite color filter material includes an infrared absorption dye A and an infrared absorption dye B. The maximum central absorption wavelength of the infrared absorption dye A is 710 ± 5 nm, the effective absorption band is 600 - 770 nm, and the minimum effective absorption wavelength ≤ 610 nm; the maximum central absorption wavelength of the infrared absorption dye B is 860 ± 5 nm, the effective absorption band is 720 - 950 nm, the minimum effective absorption wavelength ≤ 770 nm, and the maximum effective absorption wavelength ≥ 930 nm.

3. The backlight liquid crystal display module according to claim 2, characterized in that: The infrared absorption dye A adopts a copper phthalocyanine derivative or a carbon nanotube composite dye, and the infrared absorption dye B adopts a nickel dithiolene complex or a graphene-based dye.

4. The backlight liquid crystal display module according to claim 3, characterized in that: The encapsulation glue adopts a modified epoxy resin glue.

5. The backlight liquid crystal display module according to claim 2, wherein: The preparation method of the glue layer is as follows: mix the infrared absorption dye A, the infrared absorption dye B with the encapsulation glue, and then use a centrifugal stirrer to fully mix through three-stage gradient centrifugation.

6. The backlight liquid crystal display module according to claim 1, characterized in that: The LED light source includes a blue light LED light-emitting chip and a fluorescent film, and the fluorescent film is pasted on the surface of the blue light LED light-emitting chip.

7. The backlight liquid crystal display module according to claim 1, wherein: The night vision compatible LED light is driven in a zoned dimming manner.

8. The backlight liquid crystal display module according to claim 1, wherein: Graphene heat dissipation particles are doped in the composite color filter material.

9. The backlight liquid crystal display module according to claim 6, wherein: A refractive index gradient layer is arranged between the fluorescent film and the composite color filter material.

10. The backlight liquid crystal display module according to claim 6, wherein: An aluminum nitride heat conduction column is embedded at the bottom of the blue light LED chip to form a vertical heat dissipation channel with the encapsulation bracket.

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