RGB backlight lamp bead, backlight module and display screen

Abstract

The application provides an RGB backlight lamp bead, a backlight module and a display screen, and relates to the technical field of backlight. The bracket is provided with a first half bowl and a second half bowl. The first half bowl is provided with B chips and G chips. The second half bowl is provided with B chips. The B chips in the second half bowl are covered with a first fluorescent glue layer and a second fluorescent glue layer. The first fluorescent glue layer is a glue layer mixed with KSF red powder. The second fluorescent glue layer is a glue layer mixed with N compound red powder. Red light obtained by exciting KSF red powder through B chips still has part of blue light with energy. The remaining 20% blue light with energy is effectively absorbed through N compound red powder. The concentration of KSF red powder in the first fluorescent glue layer and the concentration of N compound red powder in the second fluorescent glue layer are reasonably adjusted, and the glue amount is reasonably matched. Finally, high-purity red light can be provided, so that white light with a high color gamut is formed by the B chips and the G chips. The cost of the high-color-gamut backlight module can be greatly reduced.

Description

Technical Field

[0001] This invention relates to the field of backlight technology, and more specifically, to an RGB backlight bead, a backlight module, and a display screen. Background Technology

[0002] Backlight beads are the background light source used in LCD displays. LCD displays use filters to decompose the white background light transmitted through the backlight module into the three primary colors of red, green, and blue, and then recombine them to achieve color display. In other words, LCD displays achieve graphic display by modulating the passing light. Therefore, the light emission effect of the background light source will directly affect the visual effect of the LCD display module.

[0003] In existing technologies, the chips used in backlight modules that emit blue light are the most mature, resulting in lower cost and better performance. For emitting green and red light, various solutions exist depending on the application scenario. For example, a blue chip can be used in conjunction with green or red phosphors to emit green or red light respectively. However, the emitted green and red light is impure and is commonly used in environments where color gamut requirements are not high, with the advantage of lower cost. In scenarios with high color gamut requirements, green and red chips are used directly to emit pure color light. However, green and red chips currently suffer from severe thermal drift, high cost, and insufficient stability. Therefore, there is a difficult balance between cost and high color gamut in existing backlight chips.

[0004] Therefore, in order to reduce the cost of high color gamut displays, an RGB backlight bead, a backlight module, and a display screen are proposed. Summary of the Invention

[0005] The present invention aims to solve the problem that it is difficult to balance the cost of backlight chips and high color gamut in the prior art.

[0006] To address the above problems, this invention provides an RGB backlight LED, comprising a bracket and a chip, wherein: The wafer includes B wafers and G wafers; The support is provided with a first half-bowl and a second half-bowl. The first half-bowl contains B-chips and G-chips, and the second half-bowl contains B-chips. The B-chips in the second half-bowl are covered with a first fluorescent adhesive layer and a second fluorescent adhesive layer. The first fluorescent adhesive layer is an adhesive layer mixed with KSF red powder; The second fluorescent adhesive layer is an adhesive layer mixed with nitrogen oxide red powder.

[0007] The RGB backlight bead provided by this invention has, but is not limited to, the following beneficial effects compared to existing technologies: The red light obtained by exciting KSF red powder with B-chip still contains some blue light energy. The remaining 20% ​​of blue light energy is effectively absorbed by N-type red powder. By properly adjusting the concentration of KSF red powder in the first phosphor layer and the concentration of N-type red powder in the second phosphor layer, and using an appropriate amount of adhesive, high-purity red light can be provided. This, together with B-chip and G-chip, forms a high color gamut white light, which can greatly reduce the cost of high color gamut backlight modules.

[0008] Furthermore, the KSF red powder is K 2 SiF 6: Mn 4+ The N-oxide red powder is CaAlSiN 3 Eu 2+ .

[0009] Furthermore, the concentration of the KSF red powder is 50%-80%.

[0010] Furthermore, the concentration of the N-oxide red powder is 60%-90%.

[0011] Furthermore, the B and G wafers of the first half-bowl are flip-chip configured.

[0012] Furthermore, the volume of the first bowl is greater than the volume of the second bowl.

[0013] Furthermore, the second phosphor layer is located on the side of the first phosphor layer away from the B wafer.

[0014] Furthermore, the ratio of the amount of adhesive in the first fluorescent adhesive layer to the amount of adhesive in the second fluorescent adhesive layer is 1:1-3.

[0015] The present invention also provides an RGB backlight module, including an RGB backlight LED as described above; Since the technical improvements and beneficial effects of the RGB backlight module are at least the same as those of the RGB backlight beads, the RGB backlight module will not be described in detail here. The present invention also provides a display screen, including the RGB backlight module as described above.

[0016] Since the technological improvements and beneficial effects of the display screen are at least the same as those of the RGB backlight module, the display screen will not be described in detail here. Attached Figure Description

[0017] Figure 1 This is an isometric structural diagram of an RGB backlight LED bead according to an embodiment of the present invention; Figure 2 This is a full sectional side view of an RGB backlight LED according to an embodiment of the present invention; Figure 3 This is a front view of an RGB backlight LED according to an embodiment of the present invention; Figure 4 This is a spectral detection data graph of N-oxide red phosphor LED beads; Figure 5 This is a spectral detection data graph of the LED bead with different proportions of the first and second fluorescent adhesives according to one embodiment of the present invention; Figure 6 This is a spectral detection data diagram of the LED beads with different proportions of the first and second fluorescent adhesives according to another embodiment of the present invention.

[0018] Explanation of reference numerals in the attached figures: 1-Support, 2-First half-bowl, 3-Second half-bowl, 4-B wafer, 5-G wafer, 6-First fluorescent adhesive layer, 7-Second fluorescent adhesive layer. Detailed Implementation

[0019] To make the objectives, technical solutions, and advantages of this application clearer, specific embodiments of this application are described clearly and completely below with reference to the accompanying drawings. It should be understood that the described embodiments are only a part of the embodiments of this application, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments described in this application without creative effort will fall within the scope of protection of this application.

[0020] Unless otherwise defined, all technical and scientific terms used in this application have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains; the terminology used in the specification of this application is for the purpose of describing specific embodiments only and is not intended to limit this application; the terms "comprising," "including," "having," "containing," "comprise," etc., in the specification, claims, and accompanying drawings of this application are open-ended terms, indicating that a method comprises one or more steps, or an apparatus comprises one or more elements, but do not exclude the inclusion of other steps or elements. The terms "first," "second," etc., in the specification, claims, or accompanying drawings of this application are used to distinguish different objects, not to describe a specific order or primary / secondary relationship. 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 indicated technical features. Thus, a feature defined with "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, unless otherwise stated, "a plurality of" means two or more.

[0021] In the description of this application, it should be understood that the terms "upper", "lower", "left", "right", "front", "rear", 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 application 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 application.

[0022] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," "linking," and "attachment" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal communication between two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0023] In this application, the term "and / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or B existing alone. Additionally, in this application, the character " / " generally indicates that the preceding and following related objects have an "or" relationship.

[0024] See Figures 1-3 An RGB backlight LED bead according to an embodiment of the present invention includes a bracket 1 and a chip, wherein: The chips include B chip 4 and G chip 5; The support 1 is provided with a first half-bowl cup 2 and a second half-bowl cup 3. The first half-bowl cup 2 is provided with a B chip 4 and a G chip 5. The second half-bowl cup 3 is provided with a B chip 4. The B chip 4 in the second half-bowl cup 3 is covered with a first fluorescent adhesive layer 6 and a second fluorescent adhesive layer 7. The first fluorescent adhesive layer 6 is an adhesive layer mixed with KSF red powder; The second fluorescent adhesive layer 7 is an adhesive layer mixed with nitrogen oxide red powder.

[0025] In this embodiment, B chip 4 is the chip that emits blue light, and G chip 5 is the chip that emits green light. During fabrication, a double-bowl structure is constructed on support 1, consisting of a first half-bowl 2 and a second half-bowl 3. In practical use, it is advisable to add a partition plate to a complete bowl structure to form the first half-bowl 2 and the second half-bowl 3. Additionally, adhesives need to be prepared, namely a first fluorescent adhesive mixed with KSF red powder and a second fluorescent adhesive mixed with N-oxide red powder. Based on this: Die bonding: The positive and negative electrodes of B wafer 4 and G wafer 5 are electrically connected to the preset positive and negative pads on the support 1, respectively, and B wafer 4 and G wafer 5 are fixed in the first half cup 2 and B wafer 4 is fixed in the second half cup 3 by adhesive. Baking: Curing the adhesive used for fixing using a drying device; First dispensing: The first fluorescent adhesive, prepared by mixing KSF red powder and glue, is dispensed onto the B chip 4 inside the second half-bowl 3 using a dispensing machine to form the first fluorescent adhesive layer 6; Second dispensing: The second fluorescent adhesive, prepared by mixing N-oxide red powder and glue, is dispensed onto the first fluorescent adhesive layer 6 inside the second half-bowl 3 using a dispensing machine to form the second fluorescent adhesive layer 7. Baking: The first fluorescent adhesive layer 6 and the second fluorescent adhesive layer 7 are cured using a drying device.

[0026] Furthermore, the process of applying the transparent adhesive to the first bowl is existing technology, and the specific steps and timing of application can be set independently; this solution does not impose any restrictions.

[0027] It should be noted that after the LED beads are manufactured, beam splitting and tape-making steps are required to improve the consistency of subsequent backlight module products.

[0028] In this embodiment, the RGB backlight beads directly use G chip 5 because the green purity obtained by exciting phosphors with B chip 4 is difficult to meet the requirements of high color gamut backlight modules, so G chip 5 is difficult to replace.

[0029] For red light, the red light obtained by exciting KSF red powder through B chip 4 has the characteristic of pure red. However, due to the narrow absorption band of Mn4+ in KSF for absorbing blue light, there will still be about 20% blue light energy after B chip 4 is combined with KSF. Nitrogen compound red powder has a wider absorption band for absorbing blue light, so it can effectively absorb the remaining 20% ​​of blue light energy. Since the blue light energy is only 20%, it will not exceed the original absorption capacity of nitrogen compound for blue light. By reasonably adjusting the concentration of KSF red powder in the first phosphor layer 6 and the concentration of nitrogen compound red powder in the second phosphor layer 7, and with a reasonable glue ratio, the blue energy emitted from the second half-bowl 3 can be reduced to 3%, thereby providing high-purity red light to replace the R chip (the chip that can emit red light). This, together with B chip 4 and G chip 5, forms a high color gamut white light, which can greatly reduce the cost of the high color gamut backlight module. See Figures 1 to 3 Optionally, KSF red powder is K 2 SiF 6: Mn 4+ N-oxide red powder is CaAlSiN 3: Eu 2+ .

[0030] In this embodiment, CaAlSiN 3: Eu 2+ As an N-type red phosphor, in addition to having a stronger absorption capacity for blue light, its absorption peak corresponds to the emission peak of a conventional B-type crystal, showing a high degree of matching, and it also has high thermal stability.

[0031] See Figures 1 to 3 Optionally, the concentration of KSF red powder is 50%-80%; the concentration of KSF red powder refers to: KSF red powder weight / (KSF red powder weight + glue weight). The concentration of N-oxide red powder is 60%-90%; the concentration of N-oxide red powder refers to: N-oxide red powder weight / (N-oxide red powder weight + glue weight).

[0032] In this embodiment, the concentration of KSF red powder determines the ability of blue light to excite red light, as well as the proportion of blue light energy contained in red light, while the concentration of N-oxide red powder determines the absorption capacity of the remaining blue light energy. In practical use, the concentration of KSF red powder should be 60%, and the concentration of chemical red powder should be 85% to suppress blue light, so that only pure red light is emitted in the second half-bowl 3, while ensuring the lifespan of the LED beads.

[0033] See Figures 1 to 3 Optionally, the B chip 4 and G chip 5 of the first half-bowl 2 are flipped.

[0034] In this embodiment, the electrodes of B wafer 4 and G wafer 5 are directly soldered onto the support 1 using flip-chip bonding, which can eliminate conductive lines, improve package integration, shorten the heat dissipation path, and improve heat dissipation performance.

[0035] See Figures 1 to 3 Optionally, the volume of the first bowl is greater than the volume of the second bowl.

[0036] In this embodiment, the first bowl cup needs a larger volume because it has G chip 5 and B chip 4 fixed on it, so as to facilitate the reasonable arrangement of the spacing between each chip.

[0037] See Figures 1 to 3 Optionally, the second phosphor layer 7 is located on the side of the first phosphor layer 6 away from the B wafer 4.

[0038] In this embodiment, when the B chip 4 in the second half-bowl 3 emits blue light, it excites the SKF to emit red light through the first phosphor layer 6. At this time, the red light contains a portion of weaker blue light energy (more than 10%). After the N-oxide red powder in the second phosphor absorbs the blue light energy, the blue light energy in the red light is greatly weakened, thus emitting purer red light. The red light, together with the blue light emitted by the B chip 4 in the first half-bowl 2 and the green light emitted by the G chip 5, forms high color gamut white light, which meets the requirements of the high color gamut display for the backlight module.

[0039] See Figures 1 to 3 Optionally, the volume ratio of the amount of adhesive in the first fluorescent adhesive layer 6 to the amount of adhesive in the second fluorescent adhesive layer 7 is 1:1-3.

[0040] In this embodiment, the amount of adhesive used when the first fluorescence is poor also affects the purity of the final red light; In the experiment, a spectrometer was used to measure energy data at specific wavelengths and total light energy data, thereby determining the proportion of blue light energy. like Figure 4 As shown, the glue in the second half-bowl 3 is 75% N-oxide red phosphor glue, and the total glue amount is 40. The data obtained after testing are shown in Table 1 below. The table only shows the data for wavelengths of 445-455nm. It can be seen that the overall energy ratio of the data in the blue light range is about 29%. Therefore, it can be seen that neither KSF red powder nor N-oxide red powder can produce relatively pure red light.

[0041] Table 1

[0042] like Figure 5 As shown, the adhesive in the second half-bowl 3 consisted of 60% KSF red phosphor and 85% N-oxide red phosphor. The ratio of the amount of the first fluorescent adhesive to the amount of the second fluorescent adhesive was 1:1, and the total amount of adhesive was 40. The data obtained after testing are shown in Table 2 below. The table only shows data for wavelengths of 445-455nm. It can be seen that the overall energy ratio of the data in the blue light 450nm range is about 15%. Therefore, it can be seen that when the amount of adhesive used in the first fluorescent adhesive layer 6 and the second fluorescent adhesive layer 7 is similar, although the situation is improved, the effect is not significant.

[0043] Table 2

[0044] like Figure 6As shown, the adhesive in the second half-bowl 3 consisted of 60% KSF red phosphor and 85% N-oxide red phosphor. The ratio of the amount of the first fluorescent adhesive to the amount of the second fluorescent adhesive was 1:3, and the total amount of adhesive was 40. The data obtained after testing are shown in Table 3 below. The table only shows data for wavelengths of 445-455nm. It can be seen that the overall energy ratio of the data in the blue light 450nm range is about 3%. Therefore, it can be seen that the ratio of the amount of adhesive used in the first fluorescent adhesive layer 6 to the second fluorescent adhesive layer 7 has a significant effect on the purity of red light.

[0045] Table 3

[0046] It is important to note that Figure 4-6 In the table, the horizontal axis represents the wavelength sequence number. The sequence number for 450nm is 72, for 445nm it is 67, and for 455nm it is 77. Tables 1-3 only show a small range of wavelengths for illustrative purposes. In actual testing, wavelengths from 380nm to 675nm are all measured. Figure 4-6 It is evident that the red light has good purity.

[0047] Another embodiment of the present invention provides an RGB backlight module, including the aforementioned RGB backlight beads.

[0048] Since the technological improvements and beneficial effects of RGB backlight modules are at least the same as those of RGB backlight LEDs, we will not elaborate further on RGB backlight modules.

[0049] Another embodiment of the present invention provides a display screen including the aforementioned RGB backlight module.

[0050] Since the technological improvements and beneficial effects of the display are the same as those of the RGB backlight module, the display will not be described in detail.

[0051] While the present invention has been disclosed above, its scope of protection is not limited thereto. Those skilled in the art can make various changes and modifications without departing from the spirit and scope of the present invention, and all such changes and modifications will fall within the scope of protection of the present invention.

Claims

1. An RGB backlight LED, characterized in that, Includes a support (1) and a wafer, wherein: The wafers include B wafers (4) and G wafers (5); The bracket (1) is provided with a first half-bowl (2) and a second half-bowl (3). The first half-bowl (2) is provided with a B chip (4) and a G chip (5). The second half-bowl (3) is provided with a B chip (4). The B chip (4) in the second half-bowl (3) is covered with a first fluorescent adhesive layer (6) and a second fluorescent adhesive layer (7). The first fluorescent adhesive layer (6) is an adhesive layer mixed with KSF red powder; The second fluorescent adhesive layer (7) is an adhesive layer mixed with N-oxide red powder.

2. The RGB backlight bead according to claim 1, characterized in that, The KSF red powder is K 2 SiF 6: Mn 4+ ; The N-oxide red powder is CaAlSiN 3: Eu 2+ .

3. The RGB backlight bead according to claim 1, characterized in that, The concentration of the KSF red powder is 50%-80%.

4. An RGB backlight LED bead according to claim 3, characterized in that, The concentration of the N-oxide red powder is 60%-90%.

5. An RGB backlight LED bead according to claim 1, characterized in that, The B-chip (4) and G-chip (5) of the first half-bowl (2) are flipped.

6. An RGB backlight LED bead according to claim 1, characterized in that, The volume of the first bowl is greater than the volume of the second bowl.

7. An RGB backlight LED bead according to claim 1, characterized in that, The second fluorescent adhesive layer (7) is located on the side of the first fluorescent adhesive layer (6) away from the B wafer (4).

8. An RGB backlight LED bead according to claim 7, characterized in that, The volume ratio of the amount of adhesive in the first fluorescent adhesive layer (6) to the amount of adhesive in the second fluorescent adhesive layer (7) is 1:1-3.

9. An RGB backlight module, characterized in that, Including an RGB backlight bead as described in any one of claims 1-8.

10. A display screen, characterized in that, Including the RGB backlight module as described in claim 9.

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