Display device

Abstract

The invention discloses a display device which comprises a backlight module and a display module. The backlight module comprises a substrate, a plurality of light-emitting elements arranged on a first surface of the substrate, a driving controller arranged on a second surface of the substrate, a protective layer arranged on the substrate, and a plurality of light-emitting elements electrically connected with the driving controller, the second surface is opposite to the first surface, and the protective layer is electrically connected with the driving controller. Wherein the protective layer is provided with a first opening, a plurality of gap columns and an optical film, a part of at least one gap column is arranged in the first opening of the protective layer, the optical film is arranged on the plurality of gap columns, the cross section of at least one gap column is trapezoidal, and at least one gap column is contacted with the optical film. The display module is disposed on the backlight module, wherein the plurality of light emitting elements are disposed between the display module and the substrate.

Description

[0001] This application is a divisional application of the invention patent application with the application date of July 18, 2018, the application number of 201810792577.9, and the invention name of "display device". Technical Field

[0002] The present invention relates to a display device, and particularly to a display device including a light-emitting element having a wide light divergence angle. Background Art

[0003] Flat panel display devices such as liquid crystal displays (LCDs), inorganic light-emitting diode (LED) displays, organic light-emitting diode (OLED) displays, and electroluminescent displays (ELDs) are message display technologies widely used in various electronic devices, and their characteristics of being thin, light, and low-power consumption are widely recognized. As the thickness of the display device continues to decrease, the distance or space for mixing the light emitted from the light-emitting elements in the backlight module also becomes smaller. Due to insufficient space, it is difficult for the backlight module to provide uniform light to the display module, thus having an adverse impact on the display effect of the display device. Summary of the Invention

[0004] The present invention provides a display device, which includes a backlight module and a display module. The backlight module includes a substrate, a plurality of light-emitting elements disposed on a first surface of the substrate, a driving controller disposed on a second surface of the substrate, wherein the second surface is opposite to the first surface, the plurality of light-emitting elements are electrically connected to the driving controller, a protective layer disposed on the substrate, wherein the protective layer has a first opening, a plurality of spacer pillars, wherein a part of at least one spacer pillar is disposed in the first opening of the protective layer, and an optical film disposed on the plurality of spacer pillars, wherein a cross-sectional shape of at least one spacer pillar is trapezoidal, and at least one spacer pillar contacts the optical film. The display module is disposed on the backlight module, and the plurality of light-emitting elements are disposed between the display module and the substrate. Description of the Drawings

[0005] Figure 1 Shown is a cross-sectional schematic diagram of a display device according to a first embodiment of the present invention.

[0006] Figure 2 Shown is a top view schematic diagram of a part of the backlight module of the display device according to a first embodiment of the present invention.

[0007] Figures 3A to 3DShown is a schematic diagram of examples of various backlight modules according to the second embodiment of the present invention.

[0008] Figure 4 Shown is a cross-sectional schematic diagram of a backlight module according to the third embodiment of the present invention.

[0009] Figures 5A to 5C Shown is a schematic diagram of examples of various display devices according to the fourth embodiment of the present invention.

[0010] Figures 6A to 6D Shown is a schematic diagram of examples of various display devices according to the fifth embodiment of the present invention.

[0011] Figures 7A to 7D Shown is a schematic diagram of examples of various display devices according to the sixth embodiment of the present invention.

[0012] Figures 8A to 8D Shown is a schematic diagram of examples of various display devices according to the seventh embodiment of the present invention.

[0013] Figures 9A to 9D Shown is a schematic diagram of examples of various display devices according to the eighth embodiment of the present invention.

[0014] Description of reference numerals: 10-display device; 100-backlight module; 102-light-emitting element; 1021-light-emitting chip; 1022-encapsulation layer; 1022'-light conversion layer; 104-substrate; 1041-first surface; 106-support structure; 106C-recess; 107-gap column; 108-first optical film; 110-drive controller; 112-protective layer; 114, 116-wires; 118-reflective layer; 120 -contact hole; 122-active array layer; 124-semiconductor layer; 126, 136-dielectric layer; 1281, 1282-thin film transistor; 128G-gate; 128S-source contact; 128D-drain contact; 128C-channel; 130-dielectric layer; 132-drain; 134-source; 138-connecting electrode; 140-light conversion layer; 200-display module; 202-first substrate; 204-second substrate ; 206-active array layer; 208-liquid crystal layer; 208C-tunnel-shaped cavity; 2081-retaining wall; 210-first polarizer; 212-second polarizer; 214-second optical film; 216-light conversion layer, first light conversion layer; 2161-light shielding part; 2161R, 2161G, 2161B, 220a-opening; 2162G-first light conversion part; 2162R-second light conversion part; 2163R-first part points; 2163G-second part; 2163B-third part; 218-first Bragg layer; 220-second Bragg layer; 222-black matrix; 224-third substrate; 226-semi-transmissive reflection layer; D1-first distance; D2-second distance; D3-third distance; D4-fourth distance; L-light; P1-first pixel; P2-second pixel; P3-third pixel; T1-first thickness; Tp-thickness; θ-light divergence angle. DETAILED DESCRIPTION

[0015] In order to enable those skilled in the art to understand the present invention, the present invention is described in detail below with reference to the accompanying drawings. It should be noted that in order to facilitate the reader's understanding and simplify the drawings, the multiple drawings in the present invention depict a portion of the display device, and the specific elements in the drawings are not drawn according to the actual scale. In addition, the number and size of each element in the drawing are only for illustration and are not intended to limit the scope of the present invention.

[0016] Certain words are used throughout the specification and claims of the present invention to refer to specific components. It should be understood by those skilled in the art that electronic equipment manufacturers may refer to the same components by different names. It is not intended to distinguish between components that have the same function but different names. In the following specification and claims, the words "including", "comprising", and "having" are open-ended words and should therefore be interpreted as "including but not limited to...".

[0017] When an element or a film layer is said to be on another element or another film layer, or is said to be connected to another element or another film layer, it should be understood that the element or film layer is directly on the other element or film layer, or directly connected to the other element or film layer, or there may be other elements or film layers between them. However, when an element or a film layer is said to be directly on another element or another film layer, or is said to be directly connected to another element or another film layer, it should be understood that there are no other elements or film layers between them.

[0018] It is worth mentioning that without departing from the spirit of the present invention, the technical features of different embodiments hereinafter can be combined, replaced, and matched with each other to combine another embodiment.

[0019] Please refer to Figure 1 and Figure 2 , Figure 1 FIG. shows a cross-sectional schematic view of a display device according to a first embodiment of the present invention. Figure 2 FIG. shows a top view of a part of a backlight module of a display device according to a first embodiment of the present invention, wherein Figure 1 the cross-sectional structure shown corresponds to Figure 2 the cutting line I-I' in. In this embodiment, the display device 10 is a non-self-luminous display device, such as a liquid crystal display device. As Figure 1As shown, the display device 10 includes a backlight module 100 and a display module 200 disposed on the light-emitting surface of the backlight module 100. The backlight module 100 can emit light through the display module 200, enabling the display module 200 to display an image. The backlight module 100 includes a plurality of light-emitting elements 102 capable of generating light L. The light-emitting elements 102 are inorganic light-emitting diodes or organic light-emitting diodes. In each of the light-emitting elements 102, the luminance of the light L is related to the emission angle, and the luminance and emission angle of each light-emitting element 102 exhibit a specific distribution pattern. Here, the luminance can be regarded as the intensity of the light L, and the emission angle is the angle between the direction in which the light L is emitted and a normal direction. Moreover, each light-emitting element 102 can have a maximum luminance Lx at a specific emission angle (relative to the normal direction of the light-emitting surface of the light-emitting element 102). For example, the light emitted along the normal direction of the light-emitting surface of the light-emitting element 102 from the center of the light-emitting surface of the light-emitting element 102 can have the maximum luminance Lx (100% intensity), that is, the specific emission angle corresponding to the normal direction is 0 degrees, but this is not limiting. In at least one of the light-emitting elements 102 of the present invention, the angle between 30% of the maximum luminance Lx (0.3Lx) on both sides opposite to 0 degrees is defined as a spray angle θ. The spray angle θ is designed to be applied to the light emitted from the backlight module 100, and the spray angle θ is greater than or equal to 135 degrees and less than 180 degrees. The spray angle θ can be measured from an angle-to-luminance distribution diagram in a cross-sectional view, where the angle-to-luminance distribution diagram shows the luminance distribution according to different angles. Starting from the origin of the angle-to-luminance schematic diagram in the cross-sectional view, a specific angle corresponding to 30% of the maximum Lx can be obtained on the positive side of the angle, and another specific angle corresponding to 30% of the maximum Lx can be obtained on the negative side of the angle. Moreover, the absolute value of the difference (amplitude) between the two specific angles is the spray angle. For example, the light-emitting element 102 having the above-described light distribution can be a chip scale package (CSP) light-emitting diode (LED), which does not have a relatively large size. The range of the length or width of the CSP LED can be from 0.1 millimeter (mm) to 10 millimeters, but this is not limiting.

[0020] As Figure 1 and Figure 2As shown, the backlight module 100 further includes a substrate 104, a support structure 106, a first optical film 108, a plurality of driving controllers 110, a protective layer 112, and a plurality of wires 114, 116. The light-emitting element 102 is disposed on the substrate 104 and can emit light L toward the display module 200. The backlight module 100 of this embodiment can be, for example, a direct-type backlight module. The light-emitting element 102 can be directly mounted on the substrate 104, and the light-emitting element 102 and the substrate 104 having such a structure can also be regarded as having a chip on board (COB) structure. The light-emitting element 102 can include a light-emitting chip 1021 and a packaging layer 1022 covering the light-emitting chip 1021. The light-emitting chip 1021 of this embodiment can be a blue LED chip, but is not limited thereto. In other embodiments, the light-emitting chip 1021 can also be a red LED chip, a green LED chip, a white LED chip, an ultra violet (UV) LED chip, or an LED chip of other colors. The packaging layer 1022 can include materials that can provide a protective effect on the light-emitting chip 1021. The materials can be selected from the group consisting of polyimide (PI), polycarbonate (PC), polyethylene (PE), acrylic, resin, polymer, silicon oxide (SiOx), and silicon nitride (SiNx). The materials can be electrically insulating or transparent, but are not limited thereto.

[0021] In this embodiment, the substrate 104 can include a glass substrate, and the wires 114, 116, and the driving controllers 110 are formed on the substrate 104, but are not limited thereto. In other embodiments, the substrate 104 can be a printed circuit board (PCB) having a plastic or resin-based substrate. In this embodiment, the light-emitting element 102, the driving controllers 110, and the wires 114, 116 are disposed on the first surface 1041 of the substrate 104, and at least one light-emitting element 102 and at least one driving controller 110 are electrically connected. For example, as Figure 2 shown, each light-emitting element 102 is electrically connected to a corresponding driving controller 110 via a corresponding wire 114, and the driving controllers 110 can be electrically connected to each other via the wire 116. In this embodiment, the driving controllers 110 can be disposed near the light-emitting elements 102. For example, the driving controllers 110 can be disposed adjacent to the light-emitting elements 102 or between two light-emitting elements 102, as Figure 1 and Figure 2 shown. In addition, the number or configuration of the light-emitting elements 102 and the driving controllers 110 is notFigure 1 and Figure 2 is limited to the content shown. The wire 114 and the wire 116 can be formed of metal or metal oxide. The metal can include titanium (Ti), platinum (Pt), gold (Au), nickel (Ni), aluminum (Al), molybdenum (Mo), copper (Cu), etc., and alloys of these elements. The metal oxide can include indium tin oxide (ITO) or indium zinc oxide (IZO). The drive controller 110 can include an application specific integrated circuit (ASIC), etc., which can be directly formed on the substrate 104 or mechanically mounted to the substrate 104.

[0022] In this embodiment, as Figure 1 and Figure 2As shown, a protective layer 112 is disposed on a substrate 104. The protective layer 112 covers at least two light-emitting elements 102 and at least one driving controller 110. A thickness of one of the light-emitting elements 102 is defined as a first thickness T1, and a thickness Tp of the protective layer 112 is equal to the first thickness T1. The first thickness T1 is calculated from the highest point of the light-emitting element 102 to the surface of the substrate 104 on which the light-emitting element 102 is formed. The thickness Tp of the protective layer 112 is calculated from the highest point of the protective layer 112 to the surface of the substrate 104 where no light-emitting element 102 or other components are provided. The protective layer 112 can improve problems such as the light-emitting element 102 or the driving controller 110 falling off, being scratched, suffering from leakage or electrostatic discharge (ESD) damage, or being corroded by water and oxygen due to external forces. In addition, the coverage rate of the protective layer 112 is adjustable. For example, the protective layer 112 can cover most of the substrate 104 except for the positions where the spacer columns 107 of the support structure 106 are provided, but not limited thereto. In another embodiment, the protective layer 112 can only cover the area of the substrate 104 where the light-emitting elements 102 and the driving controller 110 are provided or the area where stress accumulates in the substrate 104. In another embodiment, the backlight module 100 may not include the protective layer 112. The protective layer 112 can include materials that can provide a protective effect for the light-emitting elements 102 and the driving controller 110, and the materials can be selected from the group consisting of polyimide (PI), polycarbonate (PC), polyethylene (PE), polymethyl methacrylate (acrylic), resin, polymer, silicon oxide (SiOx), and silicon nitride (SiNx). The materials can be electrically insulating, transparent, or adhesive, but not limited thereto.

[0023] The first optical film 108 is disposed on the light-emitting element 102, covering the light-emitting surface of the light-emitting element 102, and the support structure 106 is disposed between the substrate 104 and the first optical film 108 to support the space between the substrate 104 and the first optical film 108. In this embodiment, the support structure 106 includes a plurality of spacer posts 107 for supporting the first optical film 108 and enabling the space distance between the first optical film 108 and the substrate 104 to be uniform. In this embodiment, opposite ends of each spacer post 107 are in contact with the first optical film 108 and the substrate 104 respectively, but this is not limiting. Since the height of the spacer post 107 is greater than the first thickness T1 of the light-emitting element 102, a gap is formed between the first optical film 108 and the light-emitting element 102. The distance between the first optical film 108 and the light-emitting element 102 is defined as a third distance D3. The third distance D3 can be calculated from the light-emitting element 102 to the first optical film 108 in a direction perpendicular to the surface of the first optical film 108. In addition, the ratio (D3 / T1) of the third distance D3 to the first thickness T1 ranges from 1.5 to 75. When the third distance D3 is too small (i.e., the ratio is less than 1.5), the mixing effect of the light rays L emitted by the light-emitting element 102 may be too poor, resulting in poor uniformity of the light provided by the backlight module 100. When the third distance D3 is too large (i.e., the ratio is greater than 75), the ratio of the brightness of the light finally output by the backlight module 100 to the brightness of the light emitted by the light-emitting element 102 may be too small, reducing the light extraction efficiency of the backlight module 100.

[0024] The first optical film 108 can collimate the light rays L emitted by the light-emitting element 102 and guide the light rays L to the display module 200. The first optical film 108 can be a multi-layer structure and can include, for example, a light guide plate, a diffusion sheet, a brightness enhancement film, a prism sheet, a protective sheet, etc., but is not limited thereto. In other embodiments, the first optical film 108 can be a single-layer structure.

[0025] The spacer posts 107 can be formed of an insulating material (such as PI, PC, PE, polymethyl methacrylate, resin or polymer), but this is not limiting. In addition, the cross-sectional shape of the spacer posts 107 can be trapezoidal, cylindrical or prismatic, but this is not limiting.

[0026] Such as Figure 1As shown, the display module 200 includes a first substrate 202, a second substrate 204, an active matrix (AM) layer 206, a liquid crystal layer 208, a first polarizer 210, a second polarizer 212, and a second optical film 214. The first substrate 202 and the second substrate 204 are disposed opposite to each other, and the liquid crystal layer 208 is sandwiched between the first substrate 202 and the second substrate 204, and the three form a liquid crystal cell. The first substrate 202 and the second substrate 204 may each include, for example, a transparent substrate, and each transparent substrate may be a rigid substrate such as a glass substrate or a quartz substrate, or may be a flexible substrate such as a plastic substrate, but is not limited thereto. The material of the plastic substrate may include, for example, PI, PC, or polyethylene terephthalate (PET). The active matrix layer 206 is disposed between the first substrate 202 and the liquid crystal layer 208. For example, a plurality of thin film transistors (TFTs) and other circuit elements may be disposed on a surface of the first substrate 202 to control the electric field applied to the liquid crystal layer 208.

[0027] In this embodiment, the first polarizer 210 is disposed between the liquid crystal layer 208 and the first substrate 202, the second polarizer 212 is disposed between the liquid crystal layer 208 and the second substrate 204, and the first polarizer 210 and the second polarizer 212 may be referred to as inner polarizers because they are located within the liquid crystal cell. Generally, a polarizer is attached to the outer surface of the liquid crystal cell and is referred to as an outer-attached polarizer. The first polarizer 210 and the second polarizer 212 in this embodiment may be inner wire grid polarizers (WGPs), but are not limited thereto.

[0028] In addition, a light conversion layer 216 includes a plurality of light conversion portions having quantum dot (QD) particles and a light shielding portion 2161. The light shielding portion 2161 includes a plurality of openings 2161R, a plurality of openings 2161G, and a plurality of openings 2161B, wherein each opening may correspond to the area or range of a pixel (or sub-pixel). The light shielding portion 2161 may include any material capable of blocking light, such as a metal material, a black organic material, a black inorganic material, or a photoresist material. For example, an existing material for forming a black matrix may be used to form the light shielding portion 2161. This embodiment may include a plurality of first light conversion portions 2162G and a plurality of second light conversion portions 2162R. Each first light conversion portion 2162G is disposed within one opening 2161G (a first pixel P1). The QD material or other light conversion particles within the first light conversion portion 2162G can convert the light ray L emitted by the light emitting element 102 (blue light in this embodiment, or UV light in other embodiments) into green light, so the first pixel P1 is a green pixel. Similarly, each second light conversion portion 2162R is disposed within one opening 2161R (a second pixel P2), and the QD material or other light conversion particles within the second light conversion portion 2162R can convert the light ray L emitted by the light emitting element 102 into red light, so the second pixel P2 is a red pixel. In this embodiment, the opening 2161B corresponds to a plurality of third pixels P3, where the third pixel P3 is a blue pixel. Since the light emitting element 102 emits blue light, there is no need to additionally provide blue QD material or other light conversion particles within the opening 2161B, and the blue light can directly pass through the opening 2161B and be emitted, but this is not limiting. In other embodiments, QD material or other light conversion particles that convert blue light into blue light or other colored light may also be provided. In addition, the pixel referred to herein may be a sub-pixel or pixel in the picture displayed by the display module. The color of the pixel in the present invention is not limited to the above description.

[0029] In this embodiment, the distance between two adjacent light-emitting elements 102 (a repeatable distance range, such as from one center to another center or from one edge to another edge) is defined as a first distance D1, and the distance between two adjacent pixels (a repeatable distance range, such as from one center to another center or from one edge to another edge) is defined as a second distance D2. The ratio (D1 / D2) of the first distance D1 to the second distance D2 ranges from 3 to 1000, and this ratio is defined as the LED distance per pixel distance (LDPPD) in the present invention. The first distance D1 can be calculated from a position in one light-emitting element 102 to the same position in the adjacent light-emitting element 102, and the second distance D2 can be calculated from a position in one pixel (such as a first pixel P1, a second pixel P2, or a third pixel P3) to the same position in the adjacent pixel. For example, the first distance D1 can be calculated from the center of one light-emitting element 102 to the center of the adjacent light-emitting element 102, and the second distance D2 can be calculated from the center of one pixel (such as a first pixel P1, a second pixel P2, or a third pixel P3) to the center of the adjacent pixel, but this is not limiting.

[0030] In addition, the widths of the first pixel P1, the second pixel P2, and the third pixel P3 may not be the same, so the distance between two adjacent pixels in a group of the first pixels P1, the second pixels P2, and the third pixels P3 may not be the same. In this case, the second distance D2 is defined by the distance between the two shortest adjacent pixels in the above-mentioned pixel group.

[0031] In the design of a display device 10 such as local dimming or high dynamic range (HDR), LDPPD is a reference index. For example, the light-emitting element 102 in this embodiment is a CSP LED, and its size is smaller than that of the existing LED, so that the number of CSP LEDs that can be arranged in a specific area of the substrate 104 is more than that of a display device using the existing LED under the same conditions, and the display device 10 of this embodiment can have a shorter first distance D1. Thus, the LDPPD of the display device 10 of this embodiment can be smaller than that of a display device using the existing LED. For example, the range of LDPPD in this embodiment is from 3 to 200, but this is not limiting. The display device 10 can thereby have better local dimming capabilities and the ability to adjust the pixel brightness of a smaller area.

[0032] The shape (top view) of each light-emitting element 102 may include a square, rectangle, pentagon, trapezoid, hexagon, circle, ellipse, rhombus, octagon, etc. In one embodiment, a plurality of light-emitting elements 102 may be divided into different groups and disposed in different regions of the substrate 104 respectively. The light-emitting elements 102 in each group may be arranged in an array or checkerboard pattern. For example, the light-emitting elements 102 in some groups may be arranged in an array, and the light-emitting elements 102 in other groups may be arranged in a checkerboard pattern. In another embodiment, different groups may have different power losses. For example, the power loss of some groups may be 2 watts, and the power loss of other groups may be 1 watt, and the brightness of the light-emitting area may change with different power losses.

[0033] The second optical film 214 is disposed on the second substrate 204 to reduce the amount of ambient light penetrating into the display device 10 and prevent the ambient light from reacting with the QDs in the light conversion layer 216. The second optical film 214 may include a multi-layer structure, in which a plurality of film layers with high refractive index or low refractive index may be stacked on each other, but not limited thereto. In another embodiment, the second optical film 214 may include a semi-transmittance structure, in which at least one reflective layer, at least one inorganic layer, and at least one metal layer may be stacked on each other, and the stacked layers may have openings, but not limited thereto. In other embodiments, the second optical film 214 may be a quarter wavelength plate.

[0034] Other embodiments or variant embodiments of the present invention will be described in detail below. For the sake of simplicity, the same reference numerals are used to label the same elements in the following text. In order to highlight the differences between the embodiments or variants, the differences between different embodiments are described in detail below, and the repeated technical features will not be described again.

[0035] Please refer to Figures 3A to 3D , Figures 3A to 3D FIG. shows a schematic diagram of examples of various backlight modules according to the second embodiment of the present invention. As Figure 3A shown, the difference between the backlight module 100 of the example (A) of this embodiment and the first embodiment is that the thickness Tp of the protective layer 112 in the example (A) of this embodiment is greater than the first thickness T1 of the light-emitting element 102. In addition, the distance between the first optical film 108 and the protective layer 112 is defined as a fourth distance D4. The fourth distance D4 can be calculated from the top surface of the protective layer 112 to the bottom surface of the first optical film 108 along a direction perpendicular to the bottom surface of the first optical film 108 or the top surface of the protective layer 112. In addition, the ratio (D4 / T1) of the fourth distance D4 to the first thickness T1 ranges from 1.5 to 75. As Figure 3BAs shown in Example (B), the difference between the backlight module 100 of Example (B) of this embodiment and that of the first embodiment is that the thickness Tp of the protective layer 112 in Example (B) of this embodiment is less than the first thickness T1 of the light-emitting element 102. As Figure 3C and Figure 3D shown in Examples (C) and (D), the differences between the backlight module 100 of Example (C) and that of Example (A) and between the backlight module 100 of Example (D) and that of Example (B) in this embodiment are that the support structure 106 is disposed on the protective layer 112 and between the protective layer 112 and the first optical film 108. In addition, opposite ends of each spacer post 107 are in contact with the first optical film 108 and the protective layer 112 respectively, but not limited thereto.

[0036] Please refer to Figure 4 , Figure 4 which is a schematic cross-sectional view of a backlight module according to the third embodiment of the present invention. As Figure 4 shown, the difference between this embodiment and the first embodiment is that the support structure 106 forms a plurality of cavities 106C, and each light-emitting element 102 is disposed in one of the cavities 106C. The support structure 106 may be formed of an insulating material (such as resin), but not limited thereto. A reflective layer 118 is disposed on the top and side surfaces of the support structure 106, but not limited thereto. The reflective layer 118 may be formed of a reflective material (such as metal or a multi-layer reflective structure), but not limited thereto. The light L emitted by the light-emitting element 102 can be reflected by the reflective layer 118 in the cavity 106C, which can reduce the loss of the light L and improve the light utilization rate of the backlight module 100. In addition, the backlight module 100 of this embodiment may not include the protective layer 112 in the first embodiment, but not limited thereto. In another embodiment, the protective layer may be filled into each cavity and cover the light-emitting element. In another embodiment, the support structure and the protective layer may jointly form a flat top surface, and an adhesive layer may be disposed between the flat top surface and the first optical film 108, so that the backlight module and the display module can be joined through the adhesive layer. The adhesive layer may include an optically clear adhesive (OCA), but not limited thereto.

[0037] Please refer to Figures 5A to 5C , Figures 5A to 5C which is a schematic diagram of examples of various display devices according to the fourth embodiment of the present invention. As Figure 5AAs shown in Example (A) herein, the difference between the backlight module 100 of this embodiment's Example (A) and the first embodiment is that the light-emitting element 102 and the driving controller 110 are respectively disposed on two opposite surfaces of the substrate 104. For example, the light-emitting element 102 is disposed on the first surface 1041 of the substrate 104, and the driving controller 110 is disposed on the second surface 1042 of the substrate 104, where the second surface 1042 is opposite to the first surface 1041. In addition, at least one light-emitting element 102 and at least one driving controller 110 are electrically connected. For example, as Figure 5A shown in Example (A) herein, two light-emitting elements 102 are respectively electrically connected to a driving controller 110 via two wires 114 through two contact holes 120 penetrating the substrate 104. In addition, in this embodiment, the substrate 104 may be a glass substrate, and through glass vias (TGV) or through plastic vias (TPV) may be applied to the substrate 104 to enable the light-emitting element 102 and the driving controller 110 to be electrically connected, but this is not limiting.

[0038] As Figure 5B shown in Example (B) herein, at least one light bar is applied in the backlight module 100. For example, the light-emitting elements 102 may be mounted on the substrate 104 and arranged in a strip-like manner to form a light bar. The substrate 104 may be, for example, a PCB, which enables the light-emitting elements 102 disposed thereon to be electrically connected to one or more driving elements.

[0039] As Figure 5CAs shown in Example (C) therein, the backlight module 100 further includes an active matrix (AM) layer 122 disposed between the light-emitting elements 102 and the substrate 104. The active matrix layer 122 includes a semiconductor layer 124, a dielectric layer 126, a conductive layer having gates 128G, a dielectric layer 130, a conductive layer having drains 132 and sources 134, and an optional dielectric layer 136 to form a plurality of thin film transistors (TFTs) 1281, 1282 disposed between the light-emitting elements 102 and the substrate 104. The thin film transistors 1281 and 1282 serve as switching elements for driving the light-emitting elements 102 in the backlight module 100. The semiconductor layer 124 of the thin film transistor is formed of a semiconductor material, such as silicon or metal oxide, but is not limited thereto. For example, the semiconductor layer 124 may be amorphous silicon, low-temperature polycrystalline silicon, or indium gallium zinc oxide (IGZO). The semiconductor layer 124 of a thin film transistor includes a source contact 128S, a drain contact 128D, and a channel 128C disposed between the source contact 128S and the drain contact 128D. Each source 134 is electrically connected to the corresponding source contact 128S via contact holes in the dielectric layer 130 and the dielectric layer 126. Each drain 132 is electrically connected to the corresponding drain contact 128D via another contact hole in the dielectric layer 130 and the dielectric layer 126. The gates 128G are separated from the channel 128C by the dielectric layer 126 (such as a gate dielectric layer). The gates 128G, the sources 134, and the drains 132 may be formed of a conductive material (such as metal), but are not limited thereto. It is worth mentioning that Figure 5C The structure of the thin film transistor shown in Example (C) therein is only an example, and the type or structure of the TFTs of the present invention is not limited thereto, and any other suitable thin film transistor structure may replace the thin film transistors shown in the figure. For example, the thin film transistors 1281 and 1282 in this embodiment are top-gate type thin film transistors. However, in other embodiments, the thin film transistors 1281 and 1282 may also use bottom-gate type thin film transistors.

[0040] In addition, at least one of the light-emitting elements 102 is electrically connected to at least one of the thin film transistors 1281 and 1282. For example, the thin film transistors 1281 and 1282 are respectively electrically connected to the corresponding light-emitting elements 102 through connection electrodes 138. The connection electrodes 138 may be formed of a conductive material (such as metal), but are not limited thereto. In Figure 5CIn the example (C), each light-emitting element 102 is electrically connected to one thin-film transistor (thin-film transistor 1281 or thin-film transistor 1282), but this is not limiting. In other embodiments, each light-emitting element 102 may be electrically connected to multiple TFTs, or multiple light-emitting elements 102 may be electrically connected to one thin-film transistor. Additionally, in Figure 5C In the example (C), thin-film transistor 1282 partially overlaps with the corresponding light-emitting element 102 disposed thereon, or is partially covered by the corresponding light-emitting element 102 disposed thereon, while thin-film transistor 1281 does not overlap with the corresponding light-emitting element 102 disposed thereon, or is not covered by the corresponding light-emitting element 102 disposed thereon, but this is not limiting. In this case, the backlight module 100 may further include the support structure 106 described in the above embodiments, where the support structure 106 may be disposed on the active array layer 122 and cover the thin-film transistor 1281. Additionally, Figures 5A to 5C The backlight module 100 in

[0041] Please refer to Figures 6A to 6D , Figures 6A to 6D FIG. shows a schematic diagram of examples of various display devices according to the fifth embodiment of the present invention. For the sake of simplicity of the drawing, the support structure 106, the driving controller 110, and the protective layer 112 in the backlight module 100 are not shown in the figure, but this is not limiting. The backlight module 100 may be any of the backlight modules described in the above embodiments. In Figures 6A to 6D In the display module 200 of the present embodiment shown in Figure 6A , one of the polarizers 210, 212 is disposed between the first light conversion layer 216 and the liquid crystal layer 208. As Figure 6A shown in the example (A) of Figure 6A , one difference between the example (A) of Figure 6A and the first embodiment is that the first polarizer 210 in the example (A) of Figure 6A is disposed between the first substrate 202 and the first optical film 108. The first polarizer 210 in the example (A) of

[0042] As Figure 6B shown in the example (B) ofFigure 6B Example (B) is different from Example (A) in that the liquid crystal layer 208 of Example (B) includes a microcavity structure. In the microcavity structure, a plurality of tunnel-shaped cavities 208C are provided in an organic or inorganic insulating layer, where liquid crystal capsules may be respectively provided in each tunnel-shaped cavity 208C, and each liquid crystal capsule may include liquid crystal molecules surrounded by an insulating layer. An alignment film may also be formed in each tunnel-shaped cavity 208C, but is not limited thereto.

[0043] As Figure 6C shown in Example (C) of Figure 6C Example (C) is different from Example (A) in that the liquid crystal layer 208 of Example (C) does not include a retaining wall, and the display module 200 includes a first Bragg layer 218 and a second Bragg layer 220. The Bragg layer is a transflective layer with semi-transparent and semi-reflective properties. The first Bragg layer 218 is disposed between the second polarizer 212 and the light conversion layer 216, and the second Bragg layer 220 is disposed between the light conversion layer 216 and the second substrate 204. Both the first Bragg layer 218 and the second Bragg layer 220 are formed by stacked film layers, where the number of film layer stacks in the first Bragg layer 218 and the second Bragg layer 220 is different, and the thicknesses of the first Bragg layer 218 and the second Bragg layer 220 are also different, but are not limited thereto. The first Bragg layer 218 may be a complete film layer that can completely cover the light conversion layer 216, but is not limited thereto. The first Bragg layer 218 can prevent the light (green or red light in this embodiment) converted by the light conversion material (such as QD material) from being reflected back to the liquid crystal layer 208 or being reflected to adjacent pixels, so as to avoid affecting the colors of adjacent pixels. The second Bragg layer 220 includes a plurality of openings 220a, where the openings 220a may be provided corresponding to the openings 2161B (i.e., the third pixel P3) and can allow blue light to pass through. A filling layer or a plurality of scattering particles may be filled into the openings 220a. The second Bragg layer 220 covers the first light conversion part 2162G and the second light conversion part 2162R (i.e., the first pixel P1 and the second pixel P2), and the second Bragg layer 220 can block the residual blue light that is not converted by the light conversion material in the first light conversion part 2162G or the second light conversion part 2162R.

[0044] As Figure 6D shown in Example (D) of Figure 6D One difference between Example (D) and the first embodiment is Figure 6DIn the example (D), the light conversion layer 216 is disposed between the active array layer 206 and the first polarizer 210, and the structure formed by the light conversion layer 216, the active array layer 206, and the first substrate 202 may be referred to as a color filter on array (COA) structure. Figure 6D The display module 200 in the example (D) further includes a black matrix 222 disposed between the second polarizer 212 and the liquid crystal layer 208 to prevent the colors of the respective pixels from being affected by the light of other pixels. In addition, Figure 6D The display device 10 in the example (D) does not include the first optical film 108 and the second optical film 214 in the first embodiment. In the display device 10 of the example (D), the first substrate 202 may be a glass substrate, which can serve as a glass light guide plate (GLGP) to guide the light L emitted by the light-emitting element 102 to the display module 200. The second polarizer 212 and the black matrix 222 can together reflect or absorb ambient light to reduce the amount of ambient light penetrating into the display device 10 and prevent the ambient light from reacting with the light conversion material in the light conversion layer 216.

[0045] Please refer to Figures 7A to 7D , Figures 7A to 7D FIG. shows a schematic diagram of an example of various display devices according to the sixth embodiment of the present invention. For the sake of simplicity of the drawing, the support structure 106, the driving controller 110, and the protective layer 112 in the backlight module 100 are not shown in the figure, but this is not limiting. The backlight module 100 may be any of the backlight modules described in the above embodiments. In Figures 7A to 7D In the display module 200 of the present embodiment shown in FIG., one of the polarizers 210 and 212 is disposed between the first light conversion layer 216 and the liquid crystal layer 208. As Figure 7A shown in the example (A) of Figure 7A the example (A) of Figure 6A differs from Figure 7A the display module 200 of the example (A) of Figure 7A in that the display module 200 of the example (A) further includes a third substrate 224, wherein the second substrate 204 is disposed between the first substrate 202 and the third substrate 224, the light conversion layer 216 is disposed between the second substrate 204 and the third substrate 224, and the second optical film 214 is disposed on the third substrate 224. The third substrate 224 may be formed of the same material as the second substrate 204 or the first substrate 202, but this is not limiting. In addition, another difference is that

[0046] As Figure 7B shown in the example (B) of Figure 7AExample (B) is different from Example (A) in that the second polarizer 212 of Example (B) is disposed between the first substrate 202 and the light conversion layer 216. Figure 7B The second polarizer 212 of Example (B) can be referred to as an externally attached polarizer (i.e., the existing setting method), where the second polarizer 212 can be formed of, for example, a plastic material, but is not limited thereto. As Figure 7C shown in Example (C) of Figure 7C Example (C) is different from Example (A) in that the display module 100 of Example (C) does not include a third substrate disposed between the second optical film 214 and the light conversion layer 216. As Figure 7D shown in Example (D) of Figure 7D Example (D) is different from Example (C) in that the display module 200 of Example (D) does not include the second optical film and further includes a black matrix 222 disposed between the second substrate 204 and the second polarizer 212.

[0047] Please refer to Figures 8A to 8D Figures 8A to 8D FIG. shows a schematic diagram of examples of various display devices according to the seventh embodiment of the present invention. For simplicity of the drawing, the support structure 106, the driving controller 110, and the protective layer 112 in the backlight module 100 are not shown in the figure, but are not limited thereto. The backlight module 100 can be any of the backlight modules described in the above embodiments. In Figures 8A to 8D In the display module 200 of the present embodiment shown in Figure 8A Example (A), the light conversion layer 216 is disposed between the liquid crystal layer 208 and one of the polarizers 210 and 212. As Figure 8A shown in Example (A), Figure 8A One difference between Example (A) and the first embodiment is that the light L emitted by the light emitting element 102 is white light, and Figure 8A the light conversion material of the light conversion portion of the light conversion layer 216 in Example (A) is a color filter. The light conversion layer 216 may include a plurality of first portions 2163R for converting white light into red light, a plurality of second portions 2163G for converting white light into green light, and a plurality of third portions 2163B for converting white light into blue light, but is not limited thereto. The second portion 2163G may correspond to the first pixel P1, the first portion 2163R may correspond to the second pixel P2, and the third portion 2163B may correspond to the third pixel P3. Figure 8AIn Example (A), the second polarizer 212 is disposed on the second substrate 204, and the first polarizer 210 is disposed under the first substrate 202. The second substrate 204 is disposed between the second polarizer 212 and the light conversion layer 216, and the first substrate 202 is disposed between the active array layer 206 and the first polarizer 210. The first polarizer 210 and the second polarizer 212 can be referred to as outer polarizers, and the first polarizer 210 and the second polarizer 212 can be formed of a plastic material, but are not limited thereto. In addition, Figure 8A The display module 200 of Example (A) does not include a second optical film.

[0048] As Figure 8B shown in Example (B) of Figure 8B One difference between Example (B) and Example (A) is that in Example (B), the light conversion layer 216 is disposed between the active array layer 206 and the liquid crystal layer 208, and the structure formed by the light conversion layer 216, the active array layer 206, and the first substrate 202 can be referred to as a COA structure. The display module 200 of Example (B) further includes a black matrix 222 disposed between the second substrate 204 and the liquid crystal layer 208 to prevent the color of each pixel from being affected by the light of other pixels.

[0049] As Figure 8C shown in Example (C) of Figure 8C One difference between Example (C) and Example (A) is that each light-emitting element 102 in Example (C) further includes another light conversion layer 1022'. The light conversion layer 1022' can be used as a packaging layer for each light-emitting element 102, but is not limited thereto. The light conversion layer 1022' includes a plurality of QD particles. For example, the blue light emitted by the light-emitting chip 1021 can be converted into white light through the light conversion layer 1022', whereby the light L emitted by the light-emitting element 102 is white light, but is not limited thereto. In addition, the backlight module 100 of Example (C) does not include a first optical film, but is not limited thereto. As Figure 8D shown in Example (D) of Figure 8D The difference between Example (D) and Example (C) is that the backlight module 100 of Example (D) further includes another light conversion layer 140. The light conversion layer 140 of Example (D) is disposed entirely on the light-emitting element 102 and covers the light-emitting element 102. In addition, the light L emitted by the light-emitting element 102 is blue light, and the light L can be converted into white light after passing through the light conversion layer 140.

[0050] Please refer to Figures 9A to 9D , Figures 9A to 9DThe figure shows a schematic diagram of examples of various display devices according to the eighth embodiment of the present invention. For simplicity of the figure, the support structure 106, the driving controller 110, and the protective layer 112 in the backlight module 100 are not shown in the figure, but this is not limiting. The backlight module 100 can be any of the backlight modules described in the above embodiments. In Figures 9A to 9D In the display module 200 of the present embodiment shown, the display device 10 (or the display module 200) further includes a transflective layer 226, wherein the light conversion layer 216 is disposed between the transflective layer 226 and the light-emitting element 102. The transflective layer 226 can be a Bragg layer or a semi-transparent metal film. As Figure 9A shown in example (A) of Figure 9A example (A) of Figure 6A and example (A) of Figure 9A a difference is that the display module 200 of example (A) further includes a transflective layer 226 disposed between the second substrate 204 and the light conversion layer 216. The transflective layer 226 covers the first pixel P1 and the second pixel P2 and does not cover the third pixel P3. The transflective layer 226 can absorb the residual blue light that is not converted by the first light conversion portion 2162G and the second light conversion portion 2162R of the light conversion layer 216, and can allow the light generated by the first light conversion portion 2162G and the second light conversion portion 2162R to pass through to maintain the colors of the first pixel P1 and the second pixel P2. The transflective layer 226 can be formed by alternately stacking organic and inorganic materials, and is a transflective layer made by overlapping different refractive index dielectric layers, but this is not limiting. The refractive index difference between the dielectric layers can be greater than 0.6, but this is not limiting. In addition, Figure 9A the display module 200 of example (A) does not include a second optical film, and the liquid crystal layer 208 does not include a partition wall, but this is not limiting.

[0051] As Figure 9B shown in example (B) of Figure 9B a difference between example (B) of Figure 9C and example (A) is that the second substrate 204 is disposed between the transflective layer 226 and the light conversion layer 216. As Figure 9C shown in example (C) of Figure 6D and Figure 9C a difference between example (C) of Figure 9D and example (D) of Figure 9D is that the display module 200 of example (C) further includes a transflective layer 226 disposed between the liquid crystal layer 208 and the first polarizer 210. As

[0052] In summary, in at least one light-emitting element of the backlight module, for the light emitted by the light-emitting element, the light within the light divergence angle range of the maximum Lx with an illuminance greater than or equal to 30% is defined as the light emitted by the backlight module, where the light divergence angle is greater than or equal to 135 degrees and less than 180 degrees. Since the light divergence angle of the light emitted by the light-emitting element is greater than the beam angle of the light-emitting element in the existing display device (the angle between the 50% maximum illuminance Lx (0.5Lx) on the opposite sides of 0 degrees), a larger proportion of the light emitted by the light-emitting element can be applied to the light emitted by the backlight module of the present invention. When the thickness of the backlight module is thinned, the light emitted by the backlight module can be more uniform. In the backlight module, the protective layer can cover the light-emitting element or the drive controller. The protective layer can improve problems such as the light-emitting element or the drive controller falling off, being scratched, suffering from leakage or electrostatic discharge damage due to external forces. The ratio of the third distance (the distance between the first optical film and the light-emitting element) to the first thickness (the thickness of the light-emitting element) ranges from 1.5 to 75, so that the backlight module has better light output efficiency. In addition, the LED distance-pixel distance ratio (LDPPD) in the present invention ranges from 3 to 1000, thereby enabling better local dimming ability and the ability to adjust the pixel brightness of a smaller area.

[0053] The above are only the embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention can have various modifications and changes. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A display device, characterized in that, comprising: a backlight module, which comprises: a substrate; a plurality of light-emitting elements disposed on a first surface of the substrate; a driving controller disposed on a second surface of the substrate, the second surface being opposite to the first surface, and the plurality of light-emitting elements being electrically connected to the driving controller; a protective layer disposed on the substrate, wherein the protective layer has a first opening; a plurality of spacer pillars, wherein a part of at least one of the plurality of spacer pillars is disposed in the first opening of the protective layer; and an optical film disposed on the plurality of spacer pillars, wherein a cross-sectional shape of at least one of the spacer pillars is trapezoidal, and the at least one spacer pillar contacts the optical film; and a display module disposed on the backlight module, wherein the plurality of light-emitting elements are disposed between the display module and the substrate.

2. The display device according to claim 1, characterized in that, the optical film is disposed on the plurality of light-emitting elements, a distance between the optical film and one of the plurality of light-emitting elements is defined as a first distance, a thickness of one of the plurality of light-emitting elements is defined as a first thickness, wherein a ratio of the first distance to the first thickness ranges from 1.5 to 75.

3. The display device according to claim 1, characterized in that, the plurality of spacer pillars form a plurality of cavities, and one of the plurality of light-emitting elements is disposed in one of the plurality of cavities.

4. The display device according to claim 1, characterized in that, the optical film is disposed on the plurality of light-emitting elements, a distance between the optical film and the protective layer is defined as a second distance, and a thickness of one of the plurality of light-emitting elements is defined as a first thickness, wherein a ratio of the second distance to the first thickness ranges from 1.5 to 75.

5. The display device according to claim 1, characterized in that, the backlight module further comprises a plurality of thin-film transistors, the plurality of thin-film transistors are disposed between the plurality of light-emitting elements and the substrate, and at least one of the plurality of light-emitting elements is electrically connected to at least one of the plurality of thin-film transistors.

6. The display device according to claim 1, characterized in that, the display device comprises a first light conversion layer disposed on the plurality of light-emitting elements, and the display module comprises: a first polarizer disposed on the backlight module; a second polarizer disposed on the first polarizer; and a liquid crystal layer disposed between the first polarizer and the second polarizer; wherein, the first polarizer is disposed between the liquid crystal layer and the backlight module, and the second polarizer is disposed between the first light conversion layer and the liquid crystal layer.

7. The display device according to claim 1, characterized in that, The cross-sectional shape of the at least one spacer column includes a first plane and a second plane, the first plane and the second plane being opposite to each other, wherein in a cross-sectional view, the width of the first plane is greater than the width of the second plane, the first plane is disposed in the first opening of the protective layer, and the second plane contacts the optical film.

8. The display device according to claim 1, wherein, the protective layer has a second opening, and at least a part of at least one of the plurality of light-emitting elements is disposed in the second opening of the protective layer.

9. The display device according to claim 8, wherein, the at least one light-emitting element includes a third surface and a fourth surface, and the fourth surface is farther from the substrate than the third surface, and the protective layer covers the fourth surface of the at least one light-emitting element.

10. The display device according to claim 8, wherein, the at least one light-emitting element includes a third surface and a fourth surface, and the fourth surface is farther from the substrate than the third surface, and the protective layer exposes the fourth surface of the at least one light-emitting element.

11. The display device according to claim 1, wherein, the plurality of light-emitting elements and the driving controller are electrically connected via a contact hole penetrating the substrate.

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