A light mixing module, a display device using the light mixing module, and a design method

Abstract

The present invention relates to a light mixing module, a display device using the light mixing module and a design method, which are characterized in that: it includes a main substrate with a printed circuit, and at least one chip-level light-emitting unit arranged on the main substrate, the chip-level light-emitting unit includes an LED chip, a backlight bracket, a shading element and a supporting element, the backlight bracket is mounted on the main substrate, the backlight bracket has a cup-shaped reflecting surface surrounding the periphery of the LED chip; the shading element is suspended above the LED chip through the supporting element. The advantages of the present invention are: the cup-shaped reflecting surface reflects the light directly emitted by the chip and reflected from the shading element to the area to be supplemented with light, which solves the problem of uneven brightness of the light-emitting layer of the light mixing module, and avoids the loss of reflected light, thereby improving the brightness and the overall display effect.

Description

Technical Field

[0001] The invention relates to a light mixing module and a display device thereof, and also to a design method of the light mixing module. Background Art

[0002] Mini LED backlight is essentially the same as LED. It is a backlight technology that greatly reduces the size of a single LED. Usually, when used as a mixed light module, the LED is packaged on a PCB board and arranged in a matrix. Since the number of LEDs is far greater than the number of CCFLs, each LED can be used as an independent light source to form a dynamic partition backlight, improve the dynamic contrast of the display device, and achieve HDR display. After the size is reduced, more LED lights are required to form a Mini LED mixed light module, and there will be more dynamic partitions, which can be easily made into curved surfaces. In terms of technical principles, Mini LED backlight is actually an upgrade of LED backlight. The original LED light bar was only one, and the light guide plate was used to achieve brightness spreading, while Mini LED backlight uses a large number of ultra-small LED light groups to achieve the backlight effect. In this way, Mini LED backlight can not only make the number of dimming partitions (Local Dimming Zones) more detailed, achieve high dynamic range (HDR) and present high contrast effects, but also shorten the optical distance (OD) to reduce the thickness of the whole machine to meet the thinning requirements.

[0003] The existing direct-type backlight module generally adopts a five-sided light source composed of a back plate, a reflector, an LED light bar, a support column, a diaphragm, etc. Since the central brightness of the five-sided LED light source is higher than that of the surroundings, the light emitted by the LED light source will be concentrated in the central area of ​​illumination, and there will be a gap between the illumination areas of the two LED light sources, resulting in dark areas and uneven light mixing.

[0004] In conventional backlight technology solutions, the five-sided LED light source has a small emitting angle, usually 150°. The light intensity directly above the LED is higher than that around it, and a lens is needed to disperse the light directly above to the surrounding area. However, the lens has a limited ability to disperse light, and dark areas are likely to appear between adjacent light sources, resulting in light and dark boundaries in the surface light source and uneven light mixing. Increasing the light mixing distance will increase the overall thickness of the backlight module, making the system thicker. Increasing the diaphragm thickness and the number of diaphragm layers will also increase the thickness of the backlight module and increase the cost. Summary of the invention

[0005] The technical problem to be solved by the present invention is to provide a light mixing module with a reflective structure, which utilizes reflected light to compensate for the dark area of ​​the backlight module, thereby solving the technical problem of uneven brightness on the light-emitting surface of the light mixing module. A display device using the light mixing module and a design method for the light mixing module are also provided.

[0006] In order to solve the above technical problems, the technical solution of the present invention is: a light mixing module, the innovation of which is: comprising a main substrate with a printed circuit, and at least one chip-level light-emitting unit arranged on the main substrate, and a diffusion plate arranged above the chip-level light-emitting unit, wherein the chip-level light-emitting unit comprises an LED chip, a backlight bracket, a shading element and a supporting element,

[0007] The LED chip is directly or indirectly mounted on the main substrate to realize drive control;

[0008] The backlight bracket is mounted on the main substrate, and the backlight bracket has a cup-shaped reflective surface surrounding the periphery of the LED chip;

[0009] The shading element is suspended above the LED chip through a supporting element;

[0010] The cup-shaped reflective surface reflects the light directly emitted by the chip and reflected from the shading element to the area to be filled with light, and defines a conical area within a certain angle range with the main light emitting direction of the LED chip as the area to be filled with light. The angle range of the area to be filled with light is θ B At 0~±30°.

[0011] Preferably, the LED chip is covered with a packaging layer, and the packaging layer is arranged on the top and side walls of the LED chip to form a spherical package or a CSP chip.

[0012] Preferably, the LED chip is an RGB three-primary color chip, and three three-primary color chips are jointly coated in the packaging layer.

[0013] Preferably, the LED chip is mounted on a sub-base, the sub-base is mounted on a main base, and the upper surface of the sub-base around the LED chip is coated with a lower reflection layer.

[0014] Preferably, the width of the lower reflection layer is between 0.5 and 1.5 mm.

[0015] Preferably, the sub-base and the backlight support are an integral structure.

[0016] Preferably, the height of the lower edge of the cup-shaped reflective surface is lower than the height of the lower surface of the LED chip.

[0017] Preferably, the lower surface of the shading element is a spherical structure or a cone structure with a center recessed downward.

[0018] Preferably, the angle between the cone surface of the cone structure on the lower surface of the shading element and the horizontal plane is 0-25°.

[0019] Preferably, the shading element and the supporting element are integrally injection-molded on the backlight bracket.

[0020] Preferably, the distance between the lower surface of the shading element and the bottom surface of the LED chip is 0.2-1.0 mm.

[0021] Preferably, the supporting element is a supporting column, the shading element is suspended directly above the LED chip through a plurality of supporting columns, and the lower end of the supporting column is fixed on the main substrate or the backlight bracket.

[0022] Preferably, the supporting element is a suspended grid-like frame, there are multiple chip-level light-emitting units, each chip-level light-emitting unit shares a grid-like frame, and a shading element located directly above the LED chip can be individually connected to the grid holes of the grid-like frame.

[0023] Preferably, the supporting element is a supporting column suspended on the lower surface of the diffusion plate, and the lower end of the supporting column is connected to the shading element.

[0024] Preferably, the support column is a transparent material column molded on the lower surface of the diffuser plate, and the lower end surface of the transparent material column is a spherical structure or an inverted cone structure with a downward protrusion in the center. A high-reflective layer is directly covered on the surface of the spherical structure or the inverted cone structure by electroplating, spraying or immersion coating, and the high-reflective layer is a shading element.

[0025] Preferably, a high reflective layer is provided on the surface of the supporting element, or the supporting element is made of a transparent material, and the top cross-section of the supporting element gradually decreases from bottom to top.

[0026] A display device is also provided, the innovation point of which is that the display device adopts the above-mentioned light mixing module as a backlight source.

[0027] A method for designing a light mixing module is also provided, wherein the innovative point is that the steps are as follows:

[0028] S1: Determine the maximum DHR value that the hybrid module needs to achieve: DHR MAX ;

[0029] S2: Select the LED chip specifications of the chip-level light-emitting unit;

[0030] S3: Select appropriate shading element specifications for chip-level light-emitting units:

[0031] D Z With D X The relationship satisfies the following conditions: X <D Z <D X +2H Z *tan30°, and H Z 0.2~1mm, D X H is the overall size of the LED chip and its packaging layer. ZThe distance between the lower surface of the shading element and the bottom surface of the LED chip, D Z is the horizontal width of the shading element;

[0032] Get D Z , H Z Size range;

[0033] S4: Calculate the cup-shaped reflector specifications of the backlight bracket:

[0034] S4.1: First, set the area to be supplemented with light according to the optical OD height of the light mixing module to improve the light intensity uniformity of the chip-level light-emitting unit at the optical OD height position, ensuring that the light intensity difference at this height does not exceed 15%:

[0035] The area within a certain angle range with the main light emitting direction of the LED chip is defined as the area to be supplemented with light. The angle range of the area to be supplemented with light is θ B ;

[0036] When the DHR of the mixed light module MAX When it is necessary to reach 2.75, set θ B -30°~+30°;

[0037] When the DHR of the mixed light module MAX When you need to reach 3.0, set θ B -30°~+30°;

[0038] When the DHR of the mixed light module MAX When it is necessary to reach 3.5, set θ B -25°~+25°;

[0039] S4.2: Then, the area that needs to be supplemented with fill light is calculated according to the total energy that needs to be supplemented in the area to be supplemented with light, so that the light in the fill light area is reflected and supplemented to the area to be supplemented with light through the cup-shaped reflective surface of the backlight bracket;

[0040] The area within a certain angle range with the main light direction of the LED chip is defined as the fill light area, and the angle range of the fill light area is θ O ;

[0041] When the DHR of the mixed light module MAX When it needs to reach 2.75, the corresponding θ is calculated O -50~-90° and 50~90°;

[0042] When the DHR of the mixed light module MAX When it needs to reach 3.0, the corresponding θ is calculated B -30°~+30°; set θ O -70~-90° and 70~90°;

[0043] When the DHR of the mixed light module MAX When it needs to reach 3.5, the corresponding θ is calculated B -25°~+25°; set θ O -75 to -90° and 75 to 90°;

[0044] S4.3: According to the light intensity curve to be achieved, the cup-shaped reflective surface of the backlight bracket is selected to reflect the light in the fill light area to between the center point and the other side edge of the area to be filled with light, and the light directly directed to the bottom layer of the cup-shaped reflective surface is reflected to the other side edge of the area to be filled with light, and the light directly directed to the top layer of the cup-shaped reflective surface is reflected to the center of the area to be filled with light; the optical paths of the two lights are used to calculate the following relationship:

[0045] Relationship 1:

[0046] L F =-OD / tan2θ F -OD*tanθ B , and L F >0;

[0047] Relationship 2:

[0048] H F =[OD*sinθ O *cos(2θ F -θ O )] / [2*sin(θ F -θ O )*cos(θ F -θ O )];

[0049] Among them, OD is known Optical OD height Location, L F H is the horizontal distance between the bottom layer of the cup-shaped reflective surface of the backlight bracket and the LED chip. F is the height of the cup-shaped reflective surface of the backlight bracket, θ F is the angle between the cup-shaped reflective surface of the backlight bracket and the horizontal plane;

[0050] Get L F , H F The functional relationship between

[0051] S4.4: Limit L F With D F Range:

[0052] Using the condition that the light directed to the bottom layer of the cup-shaped reflective surface and reflected to the other edge of the area to be light-filled needs to avoid being blocked by the shading element, we can obtain:

[0053] Relationship 3

[0054] OD*tanθ B+1 / 2D Z ≤OD*tanθ B + L = (OD * tanθ B +L F )*(0D-H Z ) / OD;

[0055] That is, OD*tanθ B +1 / 2D Z ≤(OD*tanθ B +L F )*(0D-H Z ) / OD;

[0056] L F ≥(OD*tanθ B +1 / 2D Z )*OD / (0D-H Z )-OD*tanθ B >0;

[0057] Wherein, L is the horizontal distance between the vertical line of the center of the LED chip and a light ray reflected from the bottom layer to the edge of the other side of the area to be light-filled at the height of the shading element;

[0058] Using the width range of the lower reflection layer, we can get:

[0059] Relationship 4

[0060] L F ≥L 下 +1 / 2D X , and L 下 =0.5~1.5mm;

[0061] S5: OK L F And the corresponding H F Value:

[0062] Select a specific D Z , H Z and OD values, and substitute them into equations 1, 2, 3, and 4 to calculate the values ​​that satisfy multiple of the above equations. Relational The numerical range of L F The numerical range and the corresponding H F , θ F Numerical range As the basic parameter range of the cup-shaped reflector.

[0063] The advantages of the present invention are:

[0064] (1) The present invention proposes a backlight structure that can effectively utilize part of the light reflected by the light source to compensate for the light emitted by the light emitting layer of the backlight module, thereby making the brightness distribution of the light emitting layer more uniform. This method of reflected light compensation not only solves the problem of uneven brightness of the light emitting layer of the mixing light module, but also avoids the loss of reflected light, thereby improving the brightness and overall display effect.

[0065] (2) After adopting the backlight structure of the present invention, the arrangement spacing of the LED light sources can be increased while keeping the thickness of the light mixing module display module unchanged, thereby reducing the amount of LED light sources used and effectively reducing the production and manufacturing costs of the light mixing module;

[0066] (3) The light compensation technology solution of the light mixing module of the present invention can achieve regional extinction, increase the dynamic display range, and further enhance the display performance.

[0067] (4) The design method of the light mixing module provided by the present invention can quickly realize the design of different HDR requirements, greatly improving the manufacturing efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0068] Figure 1 It is a schematic diagram of the structure of the light mixing module in the present invention.

[0069] Figure 2 This is a schematic diagram of the structure of the light mixing module according to Embodiment 1 of the present invention.

[0070] Figure 3 Schematic diagram of the structure of a light mixing module using the second type of supporting element in Example 1 of the present invention.

[0071] Figure 4 Schematic diagram of the structure of a light mixing module using the third type of supporting element in Example 1 of the present invention.

[0072] Figure 5 This is a schematic diagram of the structure of the light mixing module according to Embodiment 2 of the present invention.

[0073] Figure 6 The diagram shows the light intensity curve before fill light and the ideal light intensity curve in the method for quickly designing a light mixing module of the present invention.

[0074] Figure 7 This is a schematic diagram of the light-filling principle for the light-mixing layer in the method for quickly designing a light-mixing module of the present invention. DETAILED DESCRIPTION

[0075] The light mixing module of the present invention is as follows Figure 1 As shown, it includes a main substrate 1 with a printed circuit, and at least one chip-level light-emitting unit arranged on the main substrate 1, and a diffusion plate 9 arranged above the chip-level light-emitting unit, the chip-level light-emitting unit includes an LED chip 2, a backlight bracket 3, a shading element 4 and a supporting element 5, wherein,

[0076] The LED chip 2 is directly or indirectly mounted on the main substrate 1 to realize driving control. The LED chip 2 may be optionally covered with a packaging layer 8, which is arranged on the top and side walls of the LED chip to form a spherical package or a CSP chip.

[0077] The backlight bracket 3 is mounted on the main substrate 1, and the backlight bracket 3 has a cup-shaped reflective surface surrounding the periphery of the LED chip 2;

[0078] The shading element 4 is suspended above the LED chip 2 through a plurality of supporting elements 5 , and the lower ends of the supporting elements 5 are fixed on the main substrate 1 or the backlight bracket 3 .

[0079] When the above light mixing module is used as a backlight source in a display device, the height between the diffusion plate and the bottom of the LED chip 2 is the optical OD height.

[0080] On the horizontal plane where the optical OD height is located, the conical area within a certain angle range with the main light emitting direction of the LED chip is defined as the area to be supplemented with light, which is selected between -30° and +30°; the area within a certain angle range with the main light emitting direction of the LED chip is the supplementary light area, which is selected between -50° and -90° and 50° and 90°;

[0081] The cup-shaped reflective surface of the backlight bracket 3 meets the following conditions:

[0082] The light directly emitted from the chip and reflected from the shading element is reflected to the area to be lighted through the cup-shaped reflective surface of the backlight bracket. A more preferred option is to reflect the light in the light-filling area roughly between the center point and the other side edge of the area to be lighted through the cup-shaped reflective surface of the backlight bracket, and to make the light directed to the bottom layer of the cup-shaped reflective surface roughly reflected to the other side edge of the area to be lighted, and to make the light directed to the top layer of the cup-shaped reflective surface roughly reflected to the center of the area to be lighted.

[0083] Embodiment 1:

[0084] In this embodiment, Figure 2 As shown, the LED chip 2 is indirectly mounted on the main substrate 1. Specifically, the LED chip 2 is mounted on a sub-substrate 6, and the sub-substrate 6 is mounted on the main substrate 1. The upper surface of the sub-substrate 6 outside the LED chip 2 is coated with a lower reflection layer 7, which is used to reflect the light directed to the substrate to the side of the light-emitting surface, so as to achieve the effect of mixed fill light and improve the utilization rate of light. In this embodiment, the width of the lower reflection layer is 0.5 to 1.5 mm. The outside of the LED chip 2 can be covered with an encapsulation layer 8, and the encapsulation layer 8 is arranged on the top and side walls of the LED chip to form a spherical package. The encapsulation layer 8 is formed into a spherical or rectangular transparent glue by molding and dispensing, which is conducive to the emission of light and facilitates more uniform mixing of light inside.

[0085] The lower surface of the shading element 4 can be either a plane or a cone structure with a center concave downward. In this embodiment, the angle between the cone surface of the cone structure of the lower surface of the shading element 4 and the horizontal plane is greater than 0 and not greater than 25°, and is recommended to be between 5 and 25°. The distance between the lower surface of the shading element 4 and the bottom surface of the LED chip 2 is preferably between 0.2 and 1.0 mm. Within this distance condition range, the light mixing layer has good overall light mixing uniformity.

[0086] As a more detailed solution of this embodiment, the sub-base plate 6 and the backlight bracket 3 are an integrally formed structure, so that the mounting accuracy can be more accurately controlled, the number of mounting positioning times can be reduced, and the manufacturing efficiency can be improved.

[0087] In addition, there are multiple options for the supporting element 5:

[0088] The supporting element 5 is a supporting column. The shading element 4 is suspended above the LED chip 2 through several supporting columns. The lower end of the supporting column is fixed on the main substrate 1 or the backlight bracket 3. Figure 2 .

[0089] The supporting element is a supporting column suspended on the lower surface of the diffuser plate, and the lower end of the supporting column is connected to the shading element, see Figure 3 .

[0090] The supporting element is a suspended grid-like frame. There are multiple chip-level light-emitting units, and each chip-level light-emitting unit shares a grid-like frame. A shading element located directly above the LED chip can be connected separately in the grid holes of the grid-like frame. Figure 4 .

[0091] It is recommended that a high-reflection layer be provided on the surface of the support element 5, or the support element 5 be made of a transparent material, and the top cross-section of the support element preferably decreases gradually from bottom to top.

[0092] As a more detailed solution of this embodiment, the height of the lower edge of the cup-shaped reflective surface of the backlight bracket 3 should be lower than the height of the lower surface of the LED chip 2, so that a larger range of light can be collected for reflection.

[0093] Embodiment 2:

[0094] The structure of this embodiment is basically the same as that of the embodiment 1, including a main substrate 1 with a printed circuit, and at least one chip-level light-emitting unit arranged on the main substrate 1, the chip-level light-emitting unit includes an LED chip 2, a backlight bracket 3, a shading element 4 and a supporting element 5, and the connection relationship is also the same. The LED chip 2 is also covered with a packaging layer 8. The difference is that:

[0095] In this embodiment, the LED chip 2 is an RGB three-primary color chip. The three three-primary color chips 21, 22, and 23 are jointly coated in the packaging layer 8. The packaging layer 8 is preferably a transparent adhesive layer, that is, a light source packaging unit is formed by packaging multiple LED chips together.

[0096] In this embodiment, D Z With D X The relationship satisfies the following conditions: X <D Z <D X +2H Z *tan30°, and H Z 0.2~1mm, D X H is the overall size of the LED chip and its packaging layer. Z The distance between the lower surface of the shading element and the bottom surface of the LED chip 2, D Z is the horizontal width of the shading element. It should be noted that the chip size D X Including the outer packaging layer, if it is an RGB three-primary color chip, then this size is the overall size after the three three-primary color chips are jointly wrapped in the packaging layer.

[0097] This embodiment is a display device using the light mixing module of the above-mentioned embodiment 1 (the lower surface of the shading element is a plane) as a backlight source. According to different DHR requirements, the shading element preferably has the following parameters:

[0098] The maximum DHR value that the hybrid module needs to achieve is limited to DHR MAX In the art, DHR refers to the ratio of the distance between adjacent packaging units in the light mixing module to the height from the LED chip to the light mixing layer. In the first embodiment, the LED chip and the packaging layer are used as a packaging unit, and in the second embodiment, the three three-primary color LED chips and the packaging layer are used as a packaging unit.

[0099] DHR of mixed light module MAX =2.75, OD = 4mm:

[0100] 1.243mm≤L F ≤2.356mm, 40°≤θ F ≤60°,0<H F ≤0.696mm.

[0101] DHR of mixed light module MAX =3.0, OD = 6mm:

[0102] 1.04mm≤L F ≤1.618mm, 40°≤θ F ≤60°,0<H F≤1.044mm.

[0103] DHR of mixed light module MAX =3.5, OD = 9mm:

[0104] 0.885mm≤L F ≤1.509mm, 40°≤θ F ≤60°,0<H F ≤1.566mm.

[0105] Among them, θ F is the angle between the cup-shaped reflective surface and the horizontal plane, L F H is the distance from the bottom edge of the cup-shaped reflective surface to the center of the LED chip. F is the height of the cup-shaped reflective surface.

[0106] The light mixing module with the above structure can be used as a backlight source of a display device.

[0107] Embodiment 3

[0108] The present invention provides a method for quickly designing a light mixing module in the present invention, the steps of which are: 1.

[0109] S1: Determine the maximum DHR value that the hybrid module needs to achieve: DHR MAX ;

[0110] S2: Select the LED chip specifications of the chip-level light-emitting unit;

[0111] S3: Select appropriate shading element specifications for chip-level light-emitting units:

[0112] D Z With D X The relationship satisfies the following conditions: X <D Z <D X +2H Z *tan30°, and H Z 0.2~1mm, D X H is the overall size of the LED chip and its packaging layer. Z The distance between the lower surface of the shading element and the bottom surface of the LED chip, D Z is the horizontal width of the shading element;

[0113] Get D Z , H Z Size range;

[0114] S4: Calculate the cup-shaped reflector specifications of the backlight bracket:

[0115] S4.1: First, set the area to be supplemented with light according to the optical OD height of the light mixing module to improve the light intensity uniformity of the chip-level light-emitting unit at the optical OD height position, ensuring that the light intensity difference at this height does not exceed 15%:

[0116] The area within a certain angle range with the main light emitting direction of the LED chip is defined as the area to be supplemented with light. The angle range of the area to be supplemented with light is θ B ;

[0117] When the DHR of the mixed light module MAX When it is necessary to reach 2.75, set θ B -30°~+30°;

[0118] When the DHR of the mixed light module MAX When you need to reach 3.0, set θ B -30°~+30°;

[0119] When the DHR of the mixed light module MAX When it is necessary to reach 3.5, set θ B -25°~+25°;

[0120] S4.2: Then, the area that needs to be supplemented with fill light is calculated according to the total energy that needs to be supplemented in the area to be supplemented with light, so that the light in the fill light area is reflected and supplemented to the area to be supplemented with light through the cup-shaped reflective surface of the backlight bracket;

[0121] The area within a certain angle range with the main light direction of the LED chip is defined as the fill light area, and the angle range of the fill light area is θ O ;

[0122] When the DHR of the mixed light module MAX When it needs to reach 2.75, the corresponding θ is calculated O -50~-90° and 50~90°;

[0123] When the DHR of the mixed light module MAX When it needs to reach 3.0, the corresponding θ is calculated B -30°~+30°; set θ O -70~-90° and 70~90°;

[0124] When the DHR of the mixed light module MAX When it needs to reach 3.5, the corresponding θ is calculated B -25°~+25°; set θ O -75 to -90° and 75 to 90°;

[0125] S4.3: According to the light intensity curve to be achieved, the cup-shaped reflective surface of the backlight bracket is selected to reflect the light in the fill light area to between the center point and the other side edge of the area to be filled with light, and the light directly directed to the bottom layer of the cup-shaped reflective surface is reflected to the other side edge of the area to be filled with light, and the light directly directed to the top layer of the cup-shaped reflective surface is reflected to the center of the area to be filled with light; the optical paths of the two lights are used to calculate the following relationship:

[0126] Relationship 1:

[0127] L F =-OD / tan2θ F -OD*tanθ B , and L F >0;

[0128] Relationship 2:

[0129] H F =[OD*sinθ O *cos(2θ F -θ O )] / [2*sin(θ F -θ O )*cos(θ F -θ O )];

[0130] Among them, OD is known Optical OD height Location, L F H is the horizontal distance between the bottom layer of the cup-shaped reflective surface of the backlight bracket and the LED chip. F is the height of the cup-shaped reflective surface of the backlight bracket, θ F is the angle between the cup-shaped reflective surface of the backlight bracket and the horizontal plane;

[0131] Get L F , H F The functional relationship between

[0132] S4.4: Limit L F With D F Range:

[0133] Using the condition that the light directed to the bottom layer of the cup-shaped reflective surface and reflected to the other edge of the area to be light-filled needs to avoid being blocked by the shading element, we can obtain:

[0134] Relationship 3

[0135] OD*tanθ B +1 / 2D Z ≤OD*tanθ B + L = (OD * tanθ B +L F )*(0D-H Z ) / OD;

[0136] That is, OD*tanθ B +1 / 2D Z ≤(OD*tanθ B +L F )*(0D-H Z ) / OD;

[0137] L F ≥(OD*tanθ B +1 / 2D Z )*OD / (0D-H Z )-OD*tanθ B >0;

[0138] Wherein, L is the horizontal distance between the vertical line of the center of the LED chip and a light ray reflected from the bottom layer to the edge of the other side of the area to be light-filled at the height of the shading element;

[0139] Using the width range of the lower reflection layer, we can get:

[0140] Relationship 4

[0141] L F ≥L 下 +1 / 2D X , and L 下 =0.5~1.5mm;

[0142] S5: OK L F And the corresponding H F Value:

[0143] Select a specific D Z , H Z and OD values, and substitute them into equations 1, 2, 3, and 4 to calculate the values ​​that satisfy multiple of the above equations. Relational The numerical range of L F The numerical range and the corresponding H F , θ F Numerical range As the basic parameter range of the cup-shaped reflector.

[0144] The principle of S4.3 in this embodiment is:

[0145] like Figure 6 As shown, the dotted line in the figure is the light intensity curve of the LED chip package before supplementary lighting, and the solid line in the figure is the ideal light intensity curve. In order to achieve the ideal light intensity curve after supplementary lighting of the area to be supplemented, the present invention supplements the energy of the shadow areas A1 and A2 on both sides to area B.

[0146] It is actually achieved through two parts: Figure 7 As shown,

[0147] The light intensity of the fill light area directly irradiated to the uppermost layer of the cup-shaped reflective surface is higher than the light intensity of the fill light area directly irradiated to the lowermost layer of the cup-shaped reflective surface; see the solid line large circle area and the dotted line large circle area in the figure; at the same time, the light excited by the LED chip or the light reflected by the shading element is reflected twice by the lower reflective layer and the substrate around the LED chip to the cup-shaped reflective surface at a larger incident angle, and most of it is reflected to a point on the side of the center point of the area to be filled light, see the solid line small circle area and the dotted line small circle area in the figure.

[0148] The required relatively ideal light intensity curve is finally achieved through the superposition of the above-mentioned primary reflection and secondary reflection.

[0149] Embodiment 4:

[0150] This embodiment adopts the above design method to make DHR MAX The mixed light module needs to reach 2.75. In this embodiment, the OD is 4mm. The LED chip specifications are 760μm long, 330μm wide, 150μm high, the top packaging layer thickness of the outer packaging layer is 230μm, and the side packaging layer thickness is 120μm. Calculation results:

[0151] 1.243mm≤L F ≤2.356mm, 40°≤θ F ≤60°,0<H F ≤0.696mm,θ F When the angle is preferably 43°, the overall uniformity measured at the current OD height in this embodiment is 96.64%.

[0152] Embodiment five:

[0153] This embodiment adopts the above design method to make DHR MAX The mixed light module needs to reach 3.0. In this embodiment, the OD is 6mm. The LED chip specifications are 760μm long, 330μm wide, 150μm high, the top packaging layer thickness of the outer packaging layer is 230μm, and the side packaging layer thickness is 120μm. Calculation results:

[0154] 1.04mm≤L F ≤1.618mm, 40°≤θ F ≤60°,0<H F ≤1.044mm,θ F When the angle is preferably 45°, the overall uniformity measured at the current OD height in this embodiment is 95.91%.

[0155] Embodiment six:

[0156] This embodiment adopts the above design method to make DHR MAXThe mixed light module needs to reach 3.5. In this embodiment, the OD is 9mm. The LED chip specifications are 760μm long, 330μm wide, 150μm high, the top packaging layer thickness of the outer packaging layer is 230μm, and the side packaging layer thickness is 120μm. Calculation results:

[0157] 0.885mm≤L F ≤1.509mm, 40°≤θ F ≤60°,0<H F ≤1.566mm,θ F When the angle is preferably 54°, the overall uniformity measured at the current OD height in this embodiment is 94.86%.

Claims

1. A light mixing module, characterized in that: The invention comprises a main substrate with a printed circuit, and at least one chip-level light-emitting unit arranged on the main substrate, and a diffusion plate arranged above the chip-level light-emitting unit, wherein the chip-level light-emitting unit comprises an LED chip, a backlight bracket, a shading element and a supporting element. The LED chip is directly or indirectly mounted on the main substrate to realize drive control; The backlight bracket is mounted on the main substrate, and the backlight bracket has a cup-shaped reflective surface surrounding the periphery of the LED chip; The shading element is suspended above the LED chip through a supporting element; The cup-shaped reflective surface reflects the light directly emitted by the chip and reflected from the shading element to the area to be filled with light, and defines a conical area within a certain angle range with the main light emitting direction of the LED chip as the area to be filled with light. The angle range of the area to be filled with light is θ B 0~±30°; The design method steps of the mixed light module are as follows: S1: Determine the maximum DHR value that the hybrid module needs to achieve: DHR MAX ; S2: Select the LED chip specifications of the chip-level light-emitting unit; S3: Select appropriate shading element specifications for chip-level light-emitting units: D Z With D X The relationship satisfies the following conditions: X <D Z <D X +2H Z *tan30°, and H Z 0.2~1mm, D X H is the overall size of the LED chip and its packaging layer. Z The distance between the lower surface of the shading element and the bottom surface of the LED chip, D Z is the horizontal width of the shading element; Get D Z , H Z Size range; S4: Calculate the cup-shaped reflector specifications of the backlight bracket: S4.1: First, set the area to be filled with light according to the optical OD height of the light mixing module to improve the light intensity uniformity of the chip-level light-emitting unit at the optical OD height position, ensuring that the light intensity difference at this height does not exceed 15%: The area within a certain angle range with the main light emitting direction of the LED chip is defined as the area to be supplemented with light. The angle range of the area to be supplemented with light is θ B ; When the DHR of the mixed light module MAX When it is necessary to reach 2.75, set θ B -30°~+30°; When the DHR of the mixed light module MAX To reach 3.0, set θ B -30°~+30°; When the DHR of the mixed light module MAX When it is necessary to reach 3.5, set θ B -25°~+25°; S4.2: Then, the area that needs to be supplemented with fill light is calculated according to the total energy that needs to be supplemented in the area to be supplemented with light, so that the light in the fill light area is reflected and supplemented to the area to be supplemented with light through the cup-shaped reflective surface of the backlight bracket; The area within a certain angle range with the main light direction of the LED chip is defined as the fill light area, and the angle range of the fill light area is θ O ; When the DHR of the mixed light module MAX When it needs to reach 2.75, the corresponding θ is calculated O -50°~-90° and 50°~90°; When the DHR of the mixed light module MAX When it needs to reach 3.0, the corresponding θ is calculated B -30°~+30°; set θ O -70°~-90° and 70°~90°; When the DHR of the mixed light module MAX When it needs to reach 3.5, the corresponding θ is calculated B -25°~+25°; set θ O -75°~-90° and 75°~90°; S4.3: According to the light intensity curve to be achieved, the cup-shaped reflective surface of the backlight bracket is selected to reflect the light in the fill light area to between the center point and the other side edge of the area to be filled with light, and the light directly directed to the bottom layer of the cup-shaped reflective surface is reflected to the other side edge of the area to be filled with light, and the light directly directed to the top layer of the cup-shaped reflective surface is reflected to the center of the area to be filled with light; the optical paths of the two lights are used to calculate the following relationship: Relationship 1: L F = -OD / tan2θ F -OD*tanθ B and L F > 0; Relationship 2: H F =[OD*sinθ O *cos(2θ) F -θ O )] / [2*sin(θ F -θ O )*cos(θ F -θ O )]; Where OD is the known optical OD height position, L F H is the horizontal distance between the bottom layer of the cup-shaped reflective surface of the backlight bracket and the LED chip. F is the height of the cup-shaped reflective surface of the backlight bracket, θ F is the angle between the cup-shaped reflective surface of the backlight bracket and the horizontal plane; Get L F , H F The functional relationship between S4.4: Limit L F With D F Range: Using the condition that the light directed to the bottom layer of the cup-shaped reflective surface and reflected to the other edge of the area to be light-filled needs to avoid being blocked by the shading element, we can obtain: Relationship 3 FROM*tanθ B +1 / 2D Z ≤FROM*tanθ B +L=(OD*tanθ B +L F )*(0D-H Z ) / FROM; i.e., OD * tanθ B + 1 / 2D Z ≤ (OD * tanθ B + L F ) * (0D - H Z ) / OD; L F ≥(FROM*tanθ B +1 / 2D Z )*FROM / (0D-H Z )-OD*tanθ B >0; Wherein, L is the horizontal distance between the vertical line of the center of the LED chip and a light ray reflected from the bottom layer to the edge of the other side of the area to be light-filled at the height of the shading element; Using the width range of the lower reflection layer, we can get: Relationship 4 L F ≥L 下 +1 / 2D X , and L 下 =0.5~1.5mm; S5: Determine L F And the corresponding H F Value: Select a specific D Z , H Z Substitute the OD value into equations 1, 2, 3, and 4 to calculate the value range that satisfies the above equations at the same time; F The numerical range and the corresponding H F、 θ F The numerical range is taken as the basic parameter range of the cup-shaped reflective surface.

2. The light mixing module according to claim 1, characterized in that: The LED chip is covered with a packaging layer, and the packaging layer is arranged on the top and side walls of the LED chip to form a spherical package or a CSP chip.

3. The light mixing module according to claim 2, characterized in that: The LED chip is an RGB three-primary color chip, and the three three-primary color chips are jointly coated in the packaging layer.

4. The light mixing module according to claim 1, characterized in that: The LED chip is mounted on a sub-base, the sub-base is mounted on a main base, and the upper surface of the sub-base around the LED chip is coated with a lower reflection layer.

5. The light mixing module according to claim 4, characterized in that: The width of the lower reflection layer is 0.5-1.5 mm.

6. The light mixing module according to claim 4, characterized in that: The sub-base plate and the backlight support are an integral structure.

7. The light mixing module according to claim 4, characterized in that: The height of the lower edge of the cup-shaped reflective surface is lower than the height of the lower surface of the LED chip.

8. The light mixing module according to claim 1, characterized in that: The lower surface of the shading element is a spherical structure or a cone structure with a center concave downward.

9. The light mixing module according to claim 8, characterized in that: The angle between the cone surface of the cone structure on the lower surface of the shading element and the horizontal plane is 0-25°.

10. The light mixing module according to claim 1, 8 or 9, characterized in that: The shading element and the supporting element are integrally injection-molded on the backlight bracket.

11. The light mixing module according to claim 1, characterized in that: The distance between the lower surface of the shading element and the bottom surface of the LED chip is 0.2-1.0 mm.

12. The light mixing module according to claim 1, characterized in that: The supporting element is a supporting column, and the shading element is suspended directly above the LED chip through a plurality of supporting columns, and the lower end of the supporting column is fixed on the main substrate or the backlight bracket.

13. The light mixing module according to claim 1, characterized in that: The supporting element is a suspended grid-like frame. There are multiple chip-level light-emitting units, each of which shares a grid-like frame. A shading element located directly above the LED chip is separately connected to the grid holes of the grid-like frame.

14. The light mixing module according to claim 1, characterized in that: The supporting element is a supporting column suspended on the lower surface of the diffusion plate, and the lower end of the supporting column is connected to the shading element.

15. The light mixing module according to claim 14, characterized in that: The support column is a transparent material column formed on the lower surface of the diffuser plate. The lower end surface of the transparent material column is a spherical structure or an inverted cone structure with a downward protrusion in the center. A high-reflective layer is directly covered on the surface of the spherical structure or the inverted cone structure by electroplating, spraying or immersion coating. The high-reflective layer is a shading element.

16. The light mixing module according to claim 1, 12, 13 or 14, characterized in that: The surface of the supporting element is provided with a high reflective layer, or the supporting element is made of a transparent material, and the top cross-section of the supporting element gradually decreases from bottom to top.

17. A display device, characterized in that: The display device adopts the light mixing module described in any one of claims 1 to 15 as a backlight source.

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