Display device

Abstract

The utility model discloses a display device, a backlight module of the display device comprises a substrate and a plurality of light emitting units, the plurality of light emitting units are arranged on the substrate at intervals, at least one light emitting unit comprises a plurality of chips and colloid, the plurality of chips are arranged at intervals, at least two chips emit light rays with different wavelengths, and the colloid covers the plurality of chips. The colloid comprises an optical adhesive layer and light diffusion particles, the light diffusion particles are arranged in the optical adhesive layer, and the light diffusion particles are configured to refract or reflect light emitted by the plurality of chips. The optical adhesive layer is provided with a first surface and a second surface, the first surface is arranged on the substrate, the second surface is a light emitting surface of the optical adhesive layer and is a curved surface, and the diameter of one end, close to the substrate, of the adhesive is larger than that of the other end, away from the substrate, of the adhesive in the thickness direction of the display device. The maximum height h of the colloid and the maximum diameter d of the colloid in the direction parallel to the length direction of the substrate meet the following relation: d = 0.7 h-1. 3 h. According to the display device, the light emitting uniformity of the light emitting unit can be improved.

Description

Technical Field

[0001] This application relates to the field of display technology, and more particularly to a display device. Background Technology

[0002] Display devices typically include a display panel and a backlight module. Light emitted from the backlight module is projected onto the display panel, and after passing through the panel, image information is displayed. The light source in the backlight module usually consists of multiple light-emitting units placed on a substrate. Each light-emitting unit includes multiple chips, which are covered by an adhesive. Different chips typically emit light of different colors, which are then emitted after passing through the adhesive. However, because the different chips are located at different positions on the substrate, the light emitted from different directions and of different colors is uneven.

[0003] Taking a configuration where red, green, and blue LED chips are arranged sequentially on a substrate as an example, the red and blue LED chips are located near the sides of the colloid, while the green LED chip is in the middle. When light is emitted from the side closest to the red LED chip, the optical path of the red light is shorter. However, when the green LED chip in the middle and the blue LED chip on the other side need to reach the same emission position, the optical path is longer, resulting in different light intensities and uneven light emission at different positions. Utility Model Content

[0004] This application discloses a display device that can improve the light emission uniformity of the light-emitting unit.

[0005] To achieve the above objectives, embodiments of this application disclose a display device, including:

[0006] A display panel is configured to display an image; a backlight module includes: a lamp board with multiple light-emitting units configured to provide a light beam to the display panel; a diffuser plate disposed between the lamp board and the display panel; the light-emitting units include: a first chip and a second chip, the first chip and the second chip emitting light beams with different wavelengths, the first chip emitting a red light beam and the second chip emitting a blue light beam; a substrate, the first chip and the second chip disposed on the substrate; a colloid disposed in the light beam emission path of the first chip and the second chip, the colloid comprising light-diffusing particles; a lens disposed between the colloid and the display panel; the light beams emitted by the first chip and the second chip are diffused by the colloid and then incident on the lens, exit through the lens and then incident on the diffuser plate, and finally incident on the display panel; wherein, the maximum height h of the colloid and the maximum diameter d of the colloid along the length direction parallel to the substrate satisfy the relationship: d = 0.7h ~ 1.3h.

[0007] By adding light-diffusing particles to the optical adhesive layer, the refraction and reflection of light by these particles increases the number of refractions or reflections of light of different wavelengths within the colloid, altering the original emission path of the light within the colloid. For example, a beam of light emitted from a chip near the edge of the colloid, originally destined for the edge, may reach the central region after one or more random scatterings by the light-diffusing particles. Conversely, light emitted from the central chip may also be scattered to the edge, thus breaking the direct correspondence between chip position and light emission point. This results in different positions on the light emission surface containing well-mixed light from different chips, thereby improving the uniformity of light of the same wavelength at different positions on the light emission surface, as well as the uniformity of light of different wavelengths at the same and different positions on the light emission surface, ultimately improving the light emission uniformity of the light-emitting unit.

[0008] If the maximum diameter d of the colloid along the length direction parallel to the substrate is less than 0.7h, it means that the maximum height of the colloid is too high, resulting in an overly tall and sharp shape, and a smaller curvature on the second side, which may lead to excessive light concentration, loss of lateral light, and a decrease in light efficiency.

[0009] If the maximum diameter d of the colloid along the length direction parallel to the substrate is greater than 1.3h, it means that the maximum height of the colloid is too low, resulting in an overly flat shape and a larger curvature on the second side. This leads to insufficient light-gathering ability, a short light mixing distance within the optical adhesive layer, poor light mixing effect, and easy uneven light output.

[0010] Therefore, by limiting the maximum diameter d of the colloid along the length direction parallel to the substrate to 0.7 to 1.3 times the maximum height h of the colloid, the curvature of the light-emitting surface of the colloid can be kept within a reasonable range. This improves the light-gathering effect, thereby better converging the lateral light emitted from the edge chips, improving the light mixing effect, and enhancing the uniformity of light emission. Simultaneously, it ensures that the light emitted by the chip has a large emission angle, which is beneficial for improving light extraction efficiency. Furthermore, this allows more light beams emitted by the colloid to enter the central region near the lens optical axis after reaching the lens incident surface, thus better utilizing the lens performance, improving divergence, and enhancing light emission uniformity. Attached Figure Description

[0011] To more clearly illustrate the technical solutions in the embodiments of this application, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0012] Figure 1 This is a schematic diagram of the display device disclosed in this application;

[0013] Figure 2 This is an exploded view of the display device disclosed in this application;

[0014] Figure 3 This is a schematic diagram of the structure of the light-emitting unit disclosed in this application;

[0015] Figure 4 This is one of the exploded schematic diagrams of the light-emitting unit disclosed in this application;

[0016] Figure 5 This is the second exploded view of the light-emitting unit disclosed in this application;

[0017] Figure 6 This is a cross-sectional view of the colloid disposed on the substrate as disclosed in this application;

[0018] Figure 7 The optical pattern diagram disclosed in this application is the corresponding optical pattern diagram when the maximum height of the colloid is 1.5 mm.

[0019] Figure 8 The optical pattern diagram is shown for the case where the maximum height of the colloid disclosed in this application is 2 mm.

[0020] Figure 9 The optical pattern diagram is shown when the maximum height of the colloid disclosed in this application is 2.6 mm.

[0021] Figure 10 The optical pattern diagram is shown when the maximum height of the colloid disclosed in this application is 3.2 mm.

[0022] Figure 11 for Figure 3 Sectional view at point AA;

[0023] Figure 12 This application discloses a light pattern of light emitted through a colloidal substance;

[0024] Figure 13 This application discloses a luminescence effect diagram of light emitted through a colloid. Detailed Implementation

[0025] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0026] In this application, the terms "upper," "lower," "left," "right," "front," "rear," "top," "bottom," "inner," "outer," "vertical," "horizontal," "lateral," and "longitudinal" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. These terms are primarily for the purpose of better describing this application and its embodiments, and are not intended to limit the indicated device, element, or component to having a specific orientation, or to be constructed and operated in a specific orientation.

[0027] Furthermore, in addition to indicating location or positional relationship, some of the aforementioned terms may also have other meanings. For example, the term "above" may also be used in some cases to indicate a certain dependency or connection relationship. Those skilled in the art can understand the specific meaning of these terms in this application based on the specific circumstances.

[0028] Furthermore, the terms "installation," "setup," "equipped with," "connection," and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral structure; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium, or an internal connection between two devices, components, or parts. Those skilled in the art can understand the specific meaning of these terms in this application based on the specific circumstances.

[0029] Furthermore, the terms "first," "second," etc., are primarily used to distinguish different devices, components, or parts (which may be the same or different in specific type and construction), and are not intended to indicate or imply the relative importance or quantity of the indicated devices, components, or parts. Unless otherwise stated, "a plurality of" means two or more.

[0030] With the upgrading of consumer demand and the continuous development of technology, display devices such as televisions and monitors have become indispensable products in people's lives. Display devices typically consist of a display panel and a backlight module. The light emitted by the backlight module is projected onto the display panel, and after passing through the panel, image information is displayed. The light source in the backlight module usually consists of multiple light-emitting units placed on a substrate. Each light-emitting unit includes multiple chips, which are covered by an adhesive. Different chips typically emit light of different colors, which are then emitted after passing through the adhesive. However, because the different chips are located at different positions on the substrate, the light emitted from different directions and of different colors is uneven.

[0031] Besides the factors affecting light emission uniformity described in the background section, there are other issues affecting the uneven light emission from different chips. Firstly, when light is emitted from the side closer to the red light chip, the intensity of the red light is higher. Since chips typically have a certain height, and the green and blue light chips on the other side block some of the light during lateral emission, the light from the side closer to the red light chip tends to be reddish. Similarly, the light from the side closer to the blue light chip exhibits the same effect, tending to be bluish, thus also leading to uneven light emission across the emitting surface.

[0032] Secondly, since the green light chip is in the middle, it forms a light spot in the central area after its light is emitted from the colloid. The red and blue light chips are on the sides, and the light spots they form will be close to the sides. The three cannot completely overlap, which will cause color distortion and uneven light output.

[0033] Based on this, this application incorporates light-diffusing particles into the optical adhesive layer. Since these particles refract and reflect light, they increase the number of refractions or reflections of light of different wavelengths within the colloid, altering the original emission path of the light within the colloid. For example, a beam of light emitted from a chip near the edge of the colloid, originally destined for the edge, may reach the central region after several random scatterings by the light-diffusing particles. Conversely, light emitted from the central chip may also be scattered to the edge, thus breaking the direct correspondence between chip position and light emission point. This results in different positions on the light emission surface containing well-mixed light from different chips, thereby improving the uniformity of light of the same wavelength at different positions on the light emission surface, as well as the uniformity of light of different wavelengths at the same and different positions on the light emission surface, ultimately improving the light emission uniformity of the light-emitting unit.

[0034] Meanwhile, by setting the maximum height h of the colloid to be greater than half of the maximum diameter d of the colloid along the length direction parallel to the substrate, the colloid roughly presents a raised, dome-shaped shape. Compared to a hemispherical shape, it can have a certain converging effect on light, so that light that would originally be dispersed far away (e.g., light from edge chips) is converged to a region closer to the center of the optical axis, resulting in greater spatial overlap with the light emitted by the chip at the center, thereby improving the light mixing effect of the colloid and further improving the light emission uniformity of the light-emitting unit.

[0035] The technical solution of this application will be further described below with reference to the embodiments and accompanying drawings.

[0036] See Figure 1 This application discloses a display device 1, which includes, but is not limited to, electronic display products such as televisions and computer monitors, and can be widely used in places such as homes, offices, conference halls, exhibition halls, stations, hospitals or shopping malls.

[0037] See Figure 2 In some embodiments, the display device 1 includes a display panel 100, wherein the display panel 100 may include, but is not limited to, a liquid crystal display (LCD), a light-emitting diode display (LED), an organic light-emitting diode display (OLED), or other displays that can be used to realize the image display function. The implementation method of this application does not specifically limit this.

[0038] In some embodiments, the display device 1 includes a backlight module 200, and a display panel 100 is disposed on the light-emitting side of the backlight module 200. The backlight module 200 provides backlighting, and the display panel 100 displays image information for user viewing.

[0039] In some embodiments, the backlight module 200 includes a back plate 10, which is disposed on the rear side of the display panel 100. The back plate 10 is used to install and fix the display panel 100, thereby supporting the display panel 100.

[0040] In some embodiments, the backlight module 200 may further include a lamp plate 20, a reflector, a diffuser, and an optical film group (not shown) arranged sequentially from back to front. The display panel 100 is located in front of the optical film group. The light emitted by the lamp plate 20 is reflected by the reflector and then passes through the diffuser and the optical film group before reaching the display panel 100. The liquid crystal molecules in the display panel 100 are deflected by the electric field, reducing the transmittance of the light emitted from the optical film group into the liquid crystal panel. This allows the light to be projected onto filters of different colors to form an image, thereby displaying image information on the display panel 100. The optical film group may include multiple films. The multiple films may include a brightness enhancement film and multiple prism sheets, or the multiple films may include multiple prism sheets.

[0041] See Figure 3 In some embodiments, the backlight module 200 includes a substrate 21 disposed on the back plate 10.

[0042] In some embodiments, the backlight module 200 includes a plurality of light-emitting units 22, which are spaced apart on a substrate 21. It is understood that the substrate 21, as a carrier substrate 21 for the light-emitting units 22, can be electrically connected to the light-emitting units 22 to provide light-emitting driving signals to the light-emitting units 22. The substrate 21 can be a rigid substrate 21, such as glass.

[0043] Specifically, the lamp panel 20 includes a substrate 21 and a plurality of light-emitting units 22 disposed on the substrate 21. The plurality of light-emitting units 22 can be arranged on the substrate 21 along the width and height of the display device 1.

[0044] See Figures 4 to 6 In some embodiments, at least one light-emitting unit 22 includes a plurality of chips 221, which are spaced apart, and at least two chips 221 emit light of different wavelengths.

[0045] In some embodiments, at least one light-emitting unit 22 includes a colloid 222, which covers a plurality of chips 221.

[0046] In some embodiments, the colloid 222 includes an optical adhesive layer 2221 and light-diffusing particles 2222, wherein the light-diffusing particles 2222 are disposed in the optical adhesive layer 2221 and are configured to refract or reflect light emitted from the plurality of chips 221.

[0047] It should be noted that the light-diffusing particles 2222 can be incorporated into the optical adhesive layer 2221. That is, the light-diffusing particles 2222 are mixed into the optical adhesive layer 2221 to form a slurry, and then the slurry is applied to cover multiple chips 221 by dispensing to form an adhesive 222. Of course, in other embodiments, the light-diffusing particles 2222 can be a diffusion layer disposed on one side of the optical adhesive layer 2221 or embedded inside it, as long as it can satisfy the requirements of light refraction or reflection and improve the uniformity of light mixing.

[0048] Optionally, the optical adhesive layer 2221 can be at least one of the following: epoxy resin hard adhesive, silicone, liquid optical adhesive, and UV adhesive. These optical adhesive layers 2221 not only have good bonding properties, enabling stable fixation on the substrate 21, but also provide good dispersion of light-diffusing particles 2222, which is beneficial for forming a uniform and stable slurry. Furthermore, these optical adhesive layers 2221 all have high transmittance and will not affect the brightness or other effects of light emission.

[0049] Furthermore, the light-diffusing particles 2222 can include, but are not limited to, at least one of inorganic particles, silicon particles, silicon dioxide, titanium dioxide, etc. These light-diffusing particles 2222 all have good refraction or reflection effects on light, and can homogenize the light through multiple reflections. It can be understood that the light-diffusing particles 2222 can include one type of particle, for example, only titanium dioxide. Alternatively, they can include multiple types of particles. Some particles can primarily play a reflective role; for example, when their refractive index differs significantly from that of the optical adhesive layer 2221 (taking silicone as an example), this particle can be titanium dioxide. Other particles can play a refractive role; for example, when their refractive index is close to that of the optical adhesive layer 2221 (taking silicone as an example), this particle can be silicon particles, silicon dioxide, etc.

[0050] Continue reading Figure 6 In some embodiments, the optical adhesive layer 2221 has a first surface 2221a and a second surface 2221b. The first surface 2221a is disposed on the substrate 21, and the second surface 2221b is the light-emitting surface of the optical adhesive layer 2221. The second surface 2221b is a curved surface. Along the thickness direction X of the display device 1, the diameter of the end of the adhesive 222 near the substrate 21 is larger than the diameter of the other end of the adhesive 222 away from the substrate 21.

[0051] It should be noted that the diameter of the colloid 222 gradually decreases from one end near the substrate 21 to the other end, making the colloid 222 have a curved shape that is smaller at the top and larger at the bottom. In other words, the outline of the projection of the colloid 222 onto the plane perpendicular to the substrate 21 is a parabola, and its shape is a semi-ellipse.

[0052] In some embodiments, the maximum height of colloid 222 is h, and the maximum diameter of colloid 222 is d, where h > 1 / 2d. That is, colloid 222 is a curved surface structure with a greater height than a hemisphere.

[0053] It is worth noting that the maximum diameter of the colloid 222 is the bottom diameter of the colloid 222, which is also the diameter of the first surface 2221a that contacts the substrate 21.

[0054] By adding light-diffusing particles 2222 to the optical adhesive layer 2221, the light-diffusing particles 2222 can refract and reflect light, increasing the number of refractions or reflections of light of different wavelengths within the adhesive layer 222. This alters the original emission path of the light within the adhesive layer 222. For example, a beam of light emitted from a chip 221 near the edge of the adhesive layer 222, which was originally destined for the edge, may reach the central region after one or more random scatterings by the light-diffusing particles 2222. Conversely, light emitted from the central chip 221 may also be scattered to the edge, thus breaking the direct correspondence between the chip 221 position and the light emission point. This results in light from different chips 221 and being fully mixed at different positions on the light emission surface, thereby improving the uniformity of light of the same wavelength at different positions on the light emission surface, as well as the uniformity of light of different wavelengths at the same and different positions on the light emission surface, and ultimately improving the light emission uniformity of the light-emitting unit 22.

[0055] Based on this, by setting the maximum height h of the colloid 222 to be greater than half of the maximum diameter d of the colloid 222, the colloid 222 is roughly in the shape of a raised dome. Compared with the shape of a hemisphere, it can have a certain converging effect on light, so that light that would originally be dispersed far away (e.g., the light from the edge chip 221) is converged to a region closer to the center of the optical axis, and the light emitted from the chip 221 at the center position will have a greater spatial overlap, thereby improving the light mixing effect of the colloid 222 and further improving the light emission uniformity of the light-emitting unit 22.

[0056] It is worth noting that the above solutions can not only solve the problem of light emission uniformity caused by the reasons in the background art, but also solve the problem of light emission uniformity caused by the first and second reasons mentioned in the foregoing embodiments.

[0057] Specifically, regarding the problem of uneven light output caused by blocking part of the lateral light output as mentioned in the first point, by adding light diffusing particles 2222, which are randomly distributed in the optical adhesive layer 2221, it is possible that light diffusing particles 2222 are distributed between adjacent chips 221. When the blocked light passes through these light diffusing particles, it will be refracted or reflected, changing the original path of the emitted light and causing the originally wasted light to be redirected. This allows the light to be mixed at other positions in the optical adhesive layer 2221, improving the light mixing effect and thus helping to improve the uniformity of light output.

[0058] Similarly, regarding the color shift problem caused by non-overlapping light spots mentioned in the second point, since the light diffusion particles 2222 can disrupt the original light emission path, the light emitted by different chips 221 can be diffused as evenly as possible, thereby reducing or even eliminating the color shift problem and improving the uniformity of light emission.

[0059] In some embodiments, the maximum height h of colloid 222 and the maximum diameter d of colloid 222 satisfy the relationship: d = 0.7h ~ 1.3h.

[0060] If the maximum diameter d of colloid 222 is less than 0.7h, it means that the maximum height of colloid 222 is too high, resulting in an overly tall and sharp shape of colloid 222. The curvature of the second surface 2221b is smaller, which will lead to excessive light concentration, loss of lateral light, and a decrease in light efficiency.

[0061] If the maximum diameter d of colloid 222 is greater than 1.3h, it means that the maximum height of colloid 222 is too low, resulting in the shape of colloid 222 being too flat and the curvature of the second surface 2221b being greater. This may lead to insufficient light-gathering ability, short light mixing distance within the optical adhesive layer 2221, poor light mixing effect, and easy uneven light output.

[0062] Therefore, by limiting the maximum diameter d of the colloid 222 to 0.7 to 1.3 times the maximum height h of the colloid 222, the curvature of the light-emitting surface of the colloid 222 can be kept within a reasonable range. This can improve the light-gathering effect, thereby better converging the lateral light emission of the edge chip 221, improving the light mixing effect, and enhancing the uniformity of light emission. At the same time, it can also ensure that the light emitted by the chip 221 has a large emission angle, which is conducive to improving the light emission efficiency.

[0063] Furthermore, the maximum height h of colloid 222 and the maximum diameter d of colloid 222 satisfy the relationship: d = 0.8h ~ 1.2h. In other words, the maximum height of colloid 222 and the bottom diameter of colloid 222 are between 0.8h and 1.2h.

[0064] Optionally, the maximum height h of colloid 222 and the maximum diameter d of colloid 222 satisfy the following relationship: d=0.8h~1.2h, d=1h~1.2h, d=0.8h~1h or d=0.9h~1.1h, for example, d=0.9h or d=1.15h, etc.

[0065] By further limiting the maximum height of colloid 222 to h and the maximum diameter of colloid 222 to satisfy the relationship d=0.8h~1.2h, the emission angle is ensured to be greater than 170°. While ensuring the uniformity of light mixing and the light output efficiency, it can provide a uniform and larger light spot for subsequent optical elements (such as lens 223 and reflector cup).

[0066] In some embodiments, the height of at least one chip 221 is h1, and the maximum height h of the colloid 222 is 5h1 to 10h1. That is, the maximum height of the colloid 222 is 5 to 10 times the height of the plurality of chips 221.

[0067] Optionally, the maximum height of colloid 222 can satisfy: h=6h1~9h1, h=7h1~8h1 or h=5h1~7h1, etc. For example, the maximum height of colloid 222 can be h=5h1, h=8h1 or h=10h1, etc.

[0068] Taking a chip 221 with a height of 200μm as an example, the maximum height h of the colloid 222 is 1mm~2mm.

[0069] If the maximum height of colloid 222 is less than 5h1, the difference between the maximum height of colloid 222 and the height of chip 221 will be too small, which will result in the space of light emitted from chip 221 being limited in colloid 222. This may cause light of different wavelengths to be emitted before they are fully mixed, resulting in problems such as color spots and color deviation.

[0070] If the maximum height of colloid 222 is greater than 10h1, it will cause colloid 222 to be too tall. Light will propagate in the excessively long path of colloid 222 and will be absorbed more by the optical adhesive layer 2221 and the light diffusion particles 2222, resulting in a decrease in light efficiency. In addition, it will form an excessively tall arch shape, which will cause the light to converge excessively towards the central area, resulting in local bright spots and affecting the uniformity of light output.

[0071] By limiting the maximum height of colloid 222 to 5-10 times the height of chip 221, a sufficiently large space can be provided for the light transmission path. This ensures that the light can be fully mixed and refracted out, thus ensuring the uniformity of the emitted light, while also preventing excessive absorption of the light, thereby ensuring the brightness of the emitted light.

[0072] Optionally, multiple chips 221 may have the same size. For example, if chip 221 is a cuboid, its length, width, and height are all the same.

[0073] It should be noted that the emitted light pattern after passing through colloid 222 is related to the shape of the light-emitting surface of colloid 222. When the bottom diameter remains constant, the higher the maximum height of colloid 222, the larger the emission angle. Figures 7 to 10 The diagram illustrates the change in the emission angle as the maximum height of colloid 222 gradually increases while the bottom diameter remains constant. (See attached image.) Figure 7 and Figure 8When the bottom diameter of colloid 222 is 3mm and the maximum height of colloid 222 is 1.5mm and 2mm respectively, the emitted light pattern is relatively narrow, with emission angles of approximately 155° and 160° respectively. Figure 9 and Figure 10 When the maximum height of colloid 222 increases to 2.6 mm and 3.2 mm respectively, the range of light emitted from colloid 222 gradually increases and widens, and the emission angles are approximately 170° and 175° respectively.

[0074] The above method uses colloid 222 with added light-diffusing particles 2222 to mix the light emitted by different chips 221 to a certain extent and has improved the uniformity of light mixing. However, as the technology is being pushed down to lower levels, the number of light-emitting units 22 will be further reduced, resulting in an increase in the spacing between the light-emitting units 22, further compressing the H:P limit, increasing the difficulty of product development, and aggravating the color difference in light mixing.

[0075] It should be noted that H:P refers to the distance between the light-emitting unit and the diffuser (optical mixing distance): the spacing between adjacent light-emitting units. The larger the H:P ratio, the better the display effect.

[0076] To address the above problems, in some embodiments, see [reference needed]. Figure 4 and Figure 5 as well as Figure 11 At least one light-emitting unit 22 further includes a lens 223. The lens 223 has a third surface 223a and a fourth surface 223b arranged opposite to each other. The third surface 223a is provided with a light-incident cavity 223c. The cavity wall surface of the light-incident cavity 223c forms a light-incident surface 223c1. The fourth surface 223b is provided with a recess 223d, which is located in the middle of the fourth surface 223b.

[0077] The third surface 223a is disposed on the substrate 21, the colloid 222 and multiple chips 221 are located in the light incident cavity 223c, and the light incident surface 223c1 is configured to refract the light emitted from the multiple chips 221 so that the light is refracted to the outside of the lens 223 by the fourth surface 223b.

[0078] By setting lens 223, multiple chips 221 and colloid 222 are placed in the light-receiving cavity 223c of lens 223. The light emitted by the chips 221 passes through colloid 222 and exits into the light-receiving cavity 223c. It can then diverge through the light-receiving surface 223c1 and enter the lens 223. After the light continues to travel to the fourth surface 223b, at least part of the light can diverge out of the lens 223 through the fourth surface 223b. During the light transmission process, as the light enters the lens 223 from the light-receiving cavity 223c, the angle of the light entering the lens 223 relative to the optical axis O becomes larger. When the light exits the lens 223, the angle of the light exiting the lens becomes even larger relative to the optical axis O. This results in an increased angle of the light emitted from colloid 222 after two divergences through lens 223, improving the original light pattern of the multiple chips 221, which is beneficial for increasing the size of the light spot and thus improving the H:P performance of the light-emitting unit 22. Meanwhile, since different colors of light emitted from the colloid 222 undergo multiple refractions or reflections inside the lens 223 after entering, each refraction or reflection causes different colors of light to superimpose and mix again, randomizing the propagation direction of the light, thereby further promoting the mixing of different colors of light and improving the uniformity of the mixed light.

[0079] As can be seen, this application incorporates light-diffusing particles 2222 into the optical adhesive layer 2221 and designs the shape of the optical adhesive layer 2221. Furthermore, it integrates a lens 223, which further mixes the light and, through its secondary optical action, opens the light emission angle of the adhesive 222, expanding the mixed light spot and further improving the uniformity of the emitted light. In other words, the secondary optical lens 223, through further scattering and mixing, can produce a light spot with highly uniform color.

[0080] Combination Figure 11 and Figure 12 In some embodiments, the multiple chips 221 are designated as red light chip 221a, green light chip 221b, and blue light chip 221c. When powered on, these three chips 221 can emit light of different colors.

[0081] By setting multiple chips 221 as red light chip 221a, green light chip 221b, and blue light chip 221c respectively, the light-emitting unit 22 can create various colors by mixing the three colors of red, green and blue.

[0082] Optionally, the red light chip 221a, green light chip 221b, and blue light chip 221c can be arranged sequentially in a straight line along the length of the substrate 21. Of course, as other examples, the arrangement order can also be red light chip 221a, green light chip 221b, or blue light chip 221c, or it can be red light chip 221a, blue light chip 221c, or green light chip 221b, etc., which can be set according to actual needs. This embodiment does not make specific limitations in this regard.

[0083] See Figure 12 In some embodiments, the light-diffusing particles 2222 are configured to refract or reflect the light emitted from the red light chip 221a, the green light chip 221b, and the blue light chip 221c, so that the second surface 2221b is formed as a Lambertian light-emitting surface.

[0084] It should be noted that the core of a Lambertian body lies in the fact that regardless of the direction from which light strikes the surface, or whether the light is emitted from the surface itself, the observed surface brightness is exactly the same at all viewing angles. In this application, this means that the light-emitting surface (second surface 2221b) of the colloid 222 satisfies the light-emitting characteristics of a Lambertian body per unit area. Specifically, ensuring that the light pattern emitted from the colloid 222 conforms to the characteristics of a Lambertian body is achieved by controlling the distribution of light-diffusing particles 2222 in the optical adhesive layer 2221. The design system of the light-diffusing particles 2222 will be described in detail in subsequent embodiments.

[0085] By defining a Lambertian light-emitting pattern on the light-emitting surface of the colloid 222, the different colors of light emitted by the red light chip 221a, green light chip 221b, and blue light chip 221c form white light on the light-emitting surface. This ensures that the mixed color does not change with the angle, thus guaranteeing the uniformity of the light emitted from the colloid 222 from the source, forming a "surface light source" with uniform brightness and consistent color. With this configuration, when light is incident on the lens 223, the lens 223 refracts and reflects it without introducing new colors and causing separation. This reduces or even eliminates color difference, thereby ensuring the uniformity of the light pattern and the consistency of color after passing through the lens 223, and thus ensuring the overall optical performance of the light-emitting unit 22.

[0086] The structure of the light-emitting unit 22 has been described above. In order to further understand how light-diffusing particles 2222 are added in this application to improve the uniformity of light emission, the following will be introduced in conjunction with specific embodiments.

[0087] In some embodiments, the weight ratio of light-diffusing particles 2222 is 8% to 20%. Optionally, the weight ratio of light-diffusing particles 2222 can be 8% to 15%, 15% to 20%, or 10% to 15%, etc. For example, the weight ratio of light-diffusing particles 2222 can be 10%, 12%, or 14%, etc.

[0088] If the weight ratio of light-diffusing particles 2222 is less than 8%, the content of light-diffusing particles 2222 is too low, resulting in fewer refractions or reflections of light inside the colloid 222, insufficient scattering, weak dispersion, and large color difference.

[0089] If the weight ratio of light-diffusing particles 2222 is greater than 20%, the content of light-diffusing particles 2222 is too high, which will cause excessive refraction or reflection of light inside the colloid 222. This may lead to increased absorption of light by the light-diffusing particles 2222, resulting in light loss and a decrease in luminous efficiency.

[0090] Therefore, by setting the weight ratio of the light-diffusing particles 2222 within the range of 8% to 20%, uniform light diffusion can be achieved, resulting in a softer light spot, effectively reducing chromatic aberration and dispersion, and significantly improving optical performance. Furthermore, it ensures the probability of light refraction or reflection, effectively balancing scattering effects and light loss, and enhancing luminous efficiency.

[0091] It is understandable that light is scattered when it encounters light-diffusing particles 2222 with different refractive indices, and the intensity and angle of scattering are related to the particle size of the light-diffusing particles 2222. If only particles of a single size are used, a large amount of scattering is required to achieve a good light mixing effect, which means that some light cannot effectively penetrate the particles, resulting in a decrease in light transmittance and affecting the brightness of the emitted light. To achieve good light efficiency, the particles need to have high light transmittance, which means that their ability to mix light is limited, affecting the uniformity of the emitted light. It is clear that the example of a single particle size cannot effectively achieve excellent light mixing and light efficiency.

[0092] Accordingly, in some embodiments, the light-diffusing particles 2222 include particles of at least two different sizes. For example, it may include particles of two different sizes, or particles of three different sizes, or particles of four different sizes.

[0093] It is understood that the particle size in the above-mentioned at least two different particle sizes can be a single particle size or a range of particle sizes. For example, the light-diffusing particles 2222 include two particles of different sizes, namely a first particle and a second particle, wherein both the first particle and the second particle have a single particle size. For example, the particle size of the first particle can be 5 μm, and the particle size of the second particle can be 10 μm. Alternatively, the particle sizes of the first particle and the second particle can be a range. For example, the first particle can be a particle with a particle size range of 2 μm to 5 μm, and the second particle can be a particle with a particle size range of 10 μm to 15 μm. This will be further explained in conjunction with specific embodiments later, and will not be elaborated further here.

[0094] This application, by setting light-diffusing particles 2222 of different sizes, allows particles of different sizes to work together, achieving not only good light diffusion but also preventing excessively scattered light scattering, thus effectively balancing the uniformity and luminous efficiency of the mixed light. Simultaneously, because the distribution of the multi-size light-diffusing particles 2222 within the optical adhesive layer 2221 is random and disordered after mixing, it provides scattering points that can play different roles in light. This disorder disrupts the originally ordered light emission path, forcing the light to follow a randomized path within the optical adhesive layer 2221, resulting in a more continuous and uniform angular distribution of scattered light, thereby improving the uniformity of the mixed light.

[0095] In some embodiments, the light-diffusing particles 2222 include at least a first-size particle, a second-size particle, and a third-size particle, wherein the size of the first-size particle is smaller than the size of the second-size particle, the size of the second-size particle is smaller than the size of the third-size particle, the weight ratio of the first-size particle is greater than the weight ratio of the second-size particle, and the weight ratio of the second-size particle is greater than the weight ratio of the third-size particle.

[0096] It can be understood that the particle size of the first, second, and third particles decreases sequentially, and the weight ratio of the first, second, and third particles increases sequentially. In other words, the particle size of the first, second, and third particles is inversely proportional to their corresponding weight ratio.

[0097] By setting the light-diffusing particles 2222 to at least three particle size distributions and defining the concentration relationship between particles of different sizes, a synergistic effect is generated through this inversely proportional combination of particle size and concentration. This results in a system distribution of light-diffusing particles 2222 in the optical adhesive layer 2221, consisting of a high concentration of small-sized particles, a low concentration of medium-sized particles, and an even lower concentration of large-sized particles. The high concentration of smaller first-size particles provides a large number of scattering points in the optical adhesive layer 2221, more effectively balancing different colors of light and achieving good dispersion and chromatic aberration. Furthermore, the smaller first-size particles are easier to uniformly disperse, avoiding visual defects caused by larger-size light-diffusing particles 2222. The larger second-size particles can receive scattered light from the smaller-size particles, further dispersing the beam and compensating for light loss caused by the smaller-size particles to some extent. At the same time, the low concentration of the largest third-size particles can disperse some of the concentrated beam that may have penetrated the first and second-size particles, ensuring that the color and brightness of the light emitted from the colloid 222 are consistent at different positions.

[0098] It is evident that at least three different particle sizes work together at their respective concentrations to achieve uniform light emission of different colors at the same or different positions on the light-emitting surface, even with a low content of light-diffusing particles 2222 relative to the optical adhesive layer 2221, thus solving the problem of light mixing and color deviation.

[0099] In some embodiments, the particle size of the first particle is 0~6μm. Optionally, the particle size of the first particle may include 0~3μm, 3μm~6μm, etc., for example, the particle size of the first particle may be 2μm, 3μm or 6μm, etc.

[0100] In some embodiments, the weight ratio of particles with the first particle size is 55%-82%. Optionally, the weight ratio of particles with the first particle size can be 60%-80%, 60%-70%, or 65%-75%, etc., for example, the weight ratio of particles with the first particle size can be 70%, 80%, or 82%, etc.

[0101] By setting the particle size of the first-diameter particles to 0-6 μm, Rayleigh scattering is primarily induced, resulting in nearly equal scattering effects for light of different wavelengths. This leads to high scattering intensity and uniform distribution of scattered light, effectively balancing different wavelengths. Furthermore, by setting the weight ratio of the first-diameter particles to 55%-82%, a high proportion of these particles is achieved, providing numerous scattering points within the optical adhesive layer 2221. This allows the light-diffusing particles 2222 to provide efficient scattering even at a relatively low concentration, ensuring light uniformity.

[0102] If the concentration of the first-diameter particles is insufficient, even a high overall concentration of light-diffusing particles 2222 will not achieve an effective scattering effect. On the other hand, if the concentration of the first-diameter particles is too high, the specific surface area of ​​the first-diameter particles is large, and the cumulative effect of absorption and scattering losses is more significant, which can easily lead to a reduction in light efficiency.

[0103] It is worth noting that when particles of the above-mentioned size range are used alone, strong Rayleigh scattering may cause a large amount of backscattering, that is, light is reflected back to the direction of the light source, resulting in a significant decrease in light transmittance, causing the light to be hazy and the light output efficiency to be low.

[0104] Therefore, particles of other sizes are further introduced. In some embodiments, the particle size of the second particle is 6 μm to 16 μm. Optionally, the particle size of the second particle may include 6 μm to 8 μm, 8 μm to 10 μm, or 10 μm to 16 μm, for example, the particle size of the second particle may be 8 μm, 10 μm, or 15 μm, etc.

[0105] In some embodiments, the weight ratio of the second-diameter particles is 10%-20%. Optionally, the weight ratio of the second-diameter particles can be 12%-18%, 15%-20%, or 10%-15%, etc., for example, the weight ratio of the second-diameter particles can be 10%, 15%, or 20%, etc.

[0106] By setting the particle size of the second-diameter particles to 6μm~16μm and the weight ratio to 10%-20%, some of the light lost due to scattering by the first-diameter particles can be received. This can compensate for the transmittance loss caused by the high scattering of the first-diameter particles to a certain extent, thereby reducing overall light loss and improving brightness. If the concentration of the second-diameter particles is too low, it will not compensate for the transmittance of the first-diameter particles, resulting in reduced light efficiency. If the concentration of the second-diameter particles is too high, they may locally aggregate in the optical adhesive layer 2221, causing local light spots and disrupting the light mixing uniformity achieved by the first-diameter particles.

[0107] In some embodiments, the particle size of the third particle is 16μm to 24μm. Optionally, the particle size of the third particle may include 16μm to 20μm, 20μm to 24μm, or 18μm to 22μm, etc. For example, the particle size of the third particle may be 16μm, 20μm, or 22μm, etc.

[0108] In some embodiments, the weight percentage of third-diameter particles is less than 10%. Optionally, the weight percentage of third-diameter particles may be less than 8%, 6%, or 5%, etc., for example, the weight percentage of third-diameter particles may be 3%, 5%, or 8%, etc.

[0109] By setting the particle size of the third-diameter particles to 16μm~24μm and their weight ratio to less than 10%, the light-diffusing particles 2222 contain a trace amount of large-diameter particles, avoiding concentrated transmission of light beams. Normally, a single large-diameter particle has a strong scattering ability. If the concentration of the third-diameter particles is too high, a large number of large particles will form many "concentrated transmission" channels, resulting in local bright spots on the light-emitting surface, which in turn destroys the uniformity.

[0110] As can be seen, this application uses small-diameter, high-concentration first-diameter particles to induce Rayleigh scattering, ensuring randomized scattering, controlling dispersion and chromatic aberration, and ensuring the uniformity of light mixing. Medium-diameter, medium-concentration second-diameter particles serve as an auxiliary force, compensating for transmittance and improving luminous efficiency while maintaining the light mixing effect. Large-diameter, low-concentration third-diameter particles are used to avoid clustered transmission, eliminate hot spots, and ensure the overall uniformity of emitted light.

[0111] The following will compare and illustrate the effects of adding light-diffusing particles 2222 to the colloid 222 in this application without adding light-diffusing particles 2222 and adding different concentrations of light-diffusing particles 2222 on the luminescence effect diagram. It should be noted that the luminescence effect diagram is an effect diagram of the light emitted after passing through the colloid 222.

[0112] See Figure 13 , Figure 13 Images (a), (b), and (c) in the diagrams correspond to the emission effects without the addition of light-diffusing particles 2222, with the addition of approximately 8% light-diffusing particles 2222, and with the addition of approximately 15% light-diffusing particles 2222, respectively. In these three comparison images, the shape of the colloid 222 is identical; that is, the maximum height and maximum diameter of the colloid 222 are the same, and the emission angle is greater than 170°.

[0113] As can be seen from (a) of 13, the emission pattern produced by colloid 222 without added light-diffusing particles 2222 shows a brighter central area with dispersion around it, exhibiting red on the left and blue on the right, resulting in very uneven brightness, i.e., poor uniformity of light emission. As can be seen from (b) of 13, the emission pattern produced by colloid 222 with added low amounts of light-diffusing particles 2222 shows reduced dispersion, but still exhibits local bright spots. However, as the content of light-diffusing particles 2222 increases to approximately 15%, the local bright spots are significantly reduced, and the overall light becomes white, indicating a substantial improvement in light emission uniformity.

[0114] The display device disclosed in the embodiments of this application has been described in detail above. Specific examples have been used to illustrate the principles and implementation methods of this application. The description of the above embodiments is only for the purpose of helping to understand the display device and its core ideas. At the same time, for those skilled in the art, there will be changes in the specific implementation methods and application scope based on the ideas of this application. Therefore, the content of this specification should not be construed as a limitation of this application.

Claims

1. A display device, characterized by comprising: The display device comprises: a display panel configured to display an image; a backlight module comprising: a lamp plate provided with a plurality of light-emitting units configured to provide a light beam for the display panel; a diffusion plate arranged between the lamp plate and the display panel; the light-emitting units comprising: first and second chips emitting light beams of different wavelengths, the first chip emitting a red light beam and the second chip emitting a blue light beam; a substrate on which the first and second chips are arranged; a gel arranged on a light beam emission path of the first and second chips, the gel comprising light diffusion particles; a lens arranged between the gel and the display panel; the light beams emitted by the first and second chips are incident on the lens after being diffused by the gel, are emitted by the lens, are incident on the diffusion plate, and are emitted to the display panel. The maximum height h of the gel and the maximum diameter d of the gel along a length direction parallel to the substrate satisfy the relationship: d=0.7h~1.3h.

2. The display device according to claim 1, wherein: the light-emitting units comprise a substrate on which the first and second chips are arranged; the gel comprises: an optical gel layer; light diffusion particles arranged in the optical gel layer, the light diffusion particles being configured to refract or reflect light emitted by the chips; the optical gel layer has a first surface arranged on the substrate and a second surface which is a light-emitting surface of the optical gel layer and is a curved surface.

3. The display device according to claim 2, wherein The maximum height h of the gel and the maximum diameter d of the gel along a length direction parallel to the substrate satisfy the relationship: d=0.8h~1.2h.

4. The display device according to claim 3, wherein The height of at least one of the chips is h1, and the maximum height h of the gel is 5h1~10h1.

5. The display device according to claim 1, wherein The light diffusion particles have a weight ratio of 8%~20%.

6. The display device according to claim 5, wherein The light diffusion particles comprise at least two types of particles having different particle sizes.

7. The display device according to claim 6, wherein The light diffusion particles comprise at least first, second, and third types of particles having different particle sizes, the first type of particles having a smaller particle size than the second type of particles, the second type of particles having a smaller particle size than the third type of particles, the first type of particles having a larger weight ratio than the second type of particles, and the second type of particles having a larger weight ratio than the third type of particles.

8. The display device according to claim 7, wherein The first type of particles have a particle size of 0~6μm and a weight ratio of 55%-82%; The second type of particles have a particle size of 6μm~16μm and a weight ratio of 10%-20%; The third type of particles have a particle size of 16μm~24μm and a weight ratio of less than 10%.

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