CN108919561B

CN108919561B - Display device

Info

Publication number: CN108919561B
Application number: CN201810756830.5A
Authority: CN
Inventors: 杨玄菱; 李锡烈; 黄昱嘉; 李朝暐
Original assignee: AU Optronics Corp
Current assignee: AU Optronics Corp
Priority date: 2018-05-03
Filing date: 2018-07-11
Publication date: 2021-09-28
Anticipated expiration: 2038-07-11
Also published as: CN108919561A; TW201947302A; TWI657296B

Abstract

The embodiment of the invention provides a display device. The display device comprises a first substrate, a second substrate, a light guide structure, a first light-emitting module, an element array and a liquid crystal switching layer. The first substrate has an inner surface facing the second substrate. The light guide structure is disposed on an inner surface of the first substrate. The first light-emitting module is arranged on the inner surface of the first substrate and is adjacent to one side of the light guide structure. The element array is arranged on the second substrate. The liquid crystal switching layer is arranged between the light guide structure and the second substrate.

Description

Display device

Technical Field

The present invention relates to a display device, and more particularly, to a display device with light sources disposed at the side of an active array.

Background

The flat panel display has advantages of small size and light weight, and thus can be widely applied to modern electronic products. Flat panel displays include various types, with liquid crystal displays being the most common. Generally, a liquid crystal display includes a backlight module, a pair of polarizers disposed at one side of the backlight module, and a liquid crystal module disposed between the pair of polarizers. The pair of polarizers may be used to filter the polarization state of the light. However, the polarizer reduces the transmittance of light, thereby reducing the overall optical efficiency of the liquid crystal display. In addition, the backlight module occupies a large proportion of the thickness of the liquid crystal display, which prevents the reduction of the thickness of the liquid crystal display.

Disclosure of Invention

The display device of the embodiment of the invention comprises a first substrate, a second substrate, a light guide structure, a first light-emitting module, an element array and a liquid crystal switching layer. The first substrate has an inner surface facing the second substrate. The light guide structure is disposed on an inner surface of the first substrate. The first light-emitting module is arranged on the inner surface of the first substrate and is adjacent to one side of the light guide structure. The element array is arranged on the second substrate. The liquid crystal switching layer is arranged between the light guide structure and the second substrate.

In some embodiments, the display device may further include a gap filling material and a first light recycling layer. The gap filling material covers the first light-emitting module and is adjacent to the side of the light guide structure. The first light recycling layer is arranged on the periphery of the gap filling material.

In some embodiments, the display device may further include a second light recycling layer. The second light recycling layer is disposed on the other side of the light guide structure.

In some embodiments, the display device may further include a second light emitting module. The second light emitting module is arranged on the inner surface of the first substrate. The first light-emitting module and the second light-emitting module are located on two opposite sides of the light guide structure, and the dominant wavelength range of the first light-emitting module is substantially equal to the dominant wavelength range of the second light-emitting module.

In some embodiments, the display device may further comprise a spacing structure. The spacing structure is arranged between the first substrate and the second substrate and is positioned in the liquid crystal switching layer. The spacer structure comprises a reflective material.

In some embodiments, the light guide structure may comprise a plurality of light channel structures. The first light emitting module may include a plurality of light emitting elements. The plurality of light channel structures are arranged along the second direction and extend along the first direction, and a gap is formed between every two adjacent light channel structures.

In some embodiments, each light emitting element may be positioned corresponding to and adjacent to each light channel structure.

In some embodiments, each light emitting element may be positioned corresponding to and adjacent to at least two light channel structures.

In some embodiments, the first light-emitting module may include a plurality of light-emitting elements, and the plurality of light-emitting elements may be positioned corresponding to and adjacent to the light channel structure.

The display device of the embodiment of the invention comprises a first substrate, a second substrate, a light guide structure, a light emitting module, an element array and a liquid crystal switching layer. The first substrate has a first inner surface, the second substrate has a second inner surface, and the first inner surface and the second inner surface face each other. The light guide structure is arranged on the first inner surface and comprises a plurality of light channel structures. Each light channel structure is provided with a first end face and a second end face which are opposite to each other. The refractive index of the material of the light guiding structure is 1.4 to 1.7. The light emitting module is arranged on the first inner surface, and the position of the light emitting module corresponds to a plurality of first end surfaces of the plurality of light channel structures. The element array is arranged on the second substrate. The liquid crystal switching layer is clamped between the first inner surface of the first substrate and the second inner surface of the second substrate.

In some embodiments, the material of the light guide structure may have a visible light transmittance of 20% to 99%.

In some embodiments, the light emitting module may include a plurality of light emitting elements. Each light channel structure location corresponds to each light emitting element, or at least two of the plurality of light channel structures locations correspond to each light emitting element.

In some embodiments, the display device may further include a reflective layer and an insulating protective layer. The reflecting layer is arranged on the first inner surface and is positioned between the first substrate and the light guide structure. The insulation protection layer is arranged between the reflection layer and the light guide structure.

In some embodiments, the thickness and width of each light channel structure may be 10 μm to 500 μm and 1 μm to 200 μm, respectively. The adjacent two light channel structures may have a pitch therebetween, and the pitch may be 1 μm to 100 μm.

In order to make the aforementioned and other features and advantages of the invention more comprehensible, embodiments accompanied with figures are described in detail below.

Drawings

Fig. 1A is a schematic cross-sectional view of a display device in a closed state along a first direction according to some embodiments of the invention.

Fig. 1B is a schematic cross-sectional view of a display device in an open state along a first direction according to some embodiments of the invention.

Fig. 1C is a schematic cross-sectional view of a structure comprising a first substrate, a light guiding structure, according to some embodiments of the present invention, along a second direction.

Fig. 2 to 7 are top views of a first substrate, a light guide structure and a first light emitting module (or a first light emitting module and a second light emitting module) according to some embodiments of the invention.

Description of reference numerals:

10: display device

100: first substrate

102: second substrate

110. 710: light guide structure

112. 712a, 712 b: optical channel structure

114: reflective layer

116: insulating protective layer

120. 320, 520, 620, 720: first light-emitting module

420: second light emitting module

122a, 122b, 122c, 322a, 322b, 322c, 422a, 422b, 422c, 522a, 522b, 522c, 622a, 622b, 622c, 722a, 722b, 722 c: light emitting element

124: gap filling material

126: first light recovery layer

128: second light recovery layer

130: element array

140: liquid crystal switching layer

142a, 142 b: liquid crystal alignment layer

144: transparent electrode

BK: spacer structure

D1: a first direction

D2: second direction

DV: offset amount

G: gap

L: length of

LC: liquid crystal molecules

Ne: refractive index of long axis

No: short axis index of refraction

P: connecting pad

S1: first inner surface

S2: second inner surface

SL: frame glue

T: thickness of

TS 1: first end face

TS 2: second end face

W, W1: width of

Detailed Description

Fig. 1A is a schematic cross-sectional view of a display device 10 in a closed state along a first direction D1 according to some embodiments of the present invention. Fig. 1B is a schematic cross-sectional view of the display device 10 in an open state along a first direction D1 according to some embodiments of the invention. Fig. 1C is a schematic cross-sectional view of a structure including the first substrate 100 and the light guide structure 110 along the second direction D2 according to some embodiments of the invention. Fig. 2 is a top view of the first substrate 100, the light guide structure 110, and the first light-emitting module 120 according to some embodiments of the invention.

Referring to fig. 1A and 1B, a display device 10 includes a first substrate 100 and a second substrate 102. In some embodiments, the materials of the first substrate 100 and the second substrate 102 may include glass, quartz, organic polymers, opaque/reflective materials (e.g., conductive materials, metals, wafers, ceramics, etc.), or other suitable materials. The first substrate 100 and the second substrate 102 are disposed opposite to each other. In detail, the first substrate 100 has a first inner surface S1, the second substrate 102 also has a second inner surface S2, and the first inner surface S1 faces the second inner surface S2. In some embodiments, the area of the first substrate 100 may be larger than the area of the second substrate 102. In other words, the second substrate 102 does not completely cover the first substrate 100, but exposes a portion of the first substrate 100. However, in other embodiments, the area of the first substrate 100 may be equal to or smaller than the area of the second substrate 102, and the invention is not limited thereto.

Referring to fig. 1A to fig. 1C and fig. 2, the display device 10 further includes a light guide structure 110, and the light guide structure 110 is disposed on the first inner surface S1 of the first substrate 100. In other words, the light guide structure 110 is located between the first substrate 100 and the second substrate 102. In some embodiments, the refractive index of the material of the light guiding structure 110 may be 1.4 to 1.7. In other embodiments, the refractive index of the material of the light guiding structure 110 may be 1 to 2. Further, the light guide structure 110 may have a visible light transmittance of 20% to 99%. For example, the material of the light guide structure 110 may include transparent photoresist, glass, acrylic, and any plastic material including Polyethylene (PE), Polycarbonate (PC), and acrylic (PMMA). In the present embodiment, the light guide structure 110 includes a plurality of light channel structures 112 (as shown in fig. 2). Specifically, each light channel structure 112 may be a long bar shape and extend along the first direction D1. In other words, the light tunnel structure 112 has a long axis parallel to the first direction D1. In addition, the light channel structure 112 may have a first end surface TS1 and a second end surface TS2 opposite to each other. In some embodiments, the length L of the light channel structure 112 in the first direction D1 may be 10 μm to 500 μm, and the width W of the light channel structure 112 in the second direction D2 may be 1 μm to 200 μm. The second direction D2 and the first direction D1 are staggered or intersected with each other, i.e., the first direction D1 and the second direction D2 are not parallel to each other. In some embodiments, the second direction D2 is substantially perpendicular to the first direction D1. In addition, the thickness T of the light tunnel structure 112 may be 10 μm to 500 μm. In the embodiment of fig. 2, the plurality of light tunnel structures 112 are arranged along the second direction D2, and a gap G is formed between two adjacent light tunnel structures 112 (see fig. 1C). For example, the width W1 of the gap G may be 1 μm to 100 μm.

Referring to fig. 1A to fig. 1C, in some embodiments, the display device 10 may further include a reflective layer 114 and an insulating protection layer 116, wherein the reflective layer 114 and the insulating protection layer 116 are respectively disposed between the light guide structure 110 and the first substrate 100, and the insulating protection layer 116 is disposed between the reflective layer 114 and the light guide structure 110. In some embodiments, the light guiding structure 110 does not completely cover the reflective layer 114 and the insulating protective layer 116. In other words, the light guide structure 110 exposes a portion of the reflective layer 114 and the insulating protection layer 116. In some embodiments, the reflective layer 114 and the insulating protection layer 116 may completely line the first inner surface S1 of the first substrate 100. For example, the material of the reflective layer 114 may include aluminum, silver, titanium, gold, or a combination thereof. The material of the insulating protection layer 116 may include silicon oxide, silicon nitride, or a combination thereof.

Referring to fig. 1A, fig. 1B and fig. 2, the display device 10 further includes a first light-emitting module 120. The first light-emitting module 120 is disposed on the first inner surface S1 of the first substrate 100. In some embodiments, the first light emitting module 120 may be attached on the first inner surface S1 of the first substrate 100 through the pad P. For example, the first light emitting module 120 can be bonded to the pad P by flip chip bonding (flip chip bonding) or wire bonding (wire bonding). In some embodiments, the pad P is formed on the reflective layer 114 and the insulating protection layer 116. As a result, the insulating protection layer 116 can be located between the reflective layer 114 and the pad P. In addition, the first light-emitting module 120 is adjacent to one side of the light guide structure 110. For example, as shown in fig. 2, the position of the first light-emitting module 120 may correspond to the first end surface TS1 of the optical channel structure 112. In other words, the first light emitting module 120 may be adjacent to the first end surface TS1 of the light channel structure 112 and relatively far away from the second end surface TS2 of the light channel structure 112. In such embodiments, the light emitted by the first light-emitting module 120 can enter the light channel structure 112 through the first end surface TS 1. In some embodiments, the reflective layer 114 may reflect light traveling toward the first substrate 100 from the first light-emitting module 120 to indirectly enter the light tunnel structure 112 therebetween. In other words, the reflective layer 114 can ensure that the light of the first light-emitting module 120 does not enter the first substrate 100, which causes a light leakage problem. In some embodiments, the insulating protection layer 116 covers the reflective layer 114 to prevent the reflective layer 114 from signal short-circuiting.

In some embodiments, the first light-emitting module 120 may include a plurality of light-emitting elements, and the display device 10 may include a plurality of first light-emitting modules 120 (as shown in fig. 2). For example, each light emitting module 120 may include a light emitting element 122a, a light emitting element 122b, and a light emitting element 122c, and the

light emitting elements

122a, 122b, and 122c are respectively located at corresponding positions and adjacent to the plurality of light channel structures 112. In other words, the

light emitting elements

122a, 122b and 122c are located correspondingly and adjacent to different light channel structures 112. In some embodiments, each light emitting element has a single dominant wavelength range. In such embodiments, each light emitting element may comprise one or more light emitting diodes having the same dominant wavelength range. The light emitting diode may be an inorganic light emitting diode or an organic light emitting diode, and the size (i.e., length, width, or height) of the light emitting diode may be 1 μm to 10000 μm. For example, the light emitting element 122a may include one or more red light emitting diodes, the light emitting element 122b may include one or more green light emitting diodes, and the light emitting element 122c may include one or more blue light emitting diodes. The dominant wavelength of light emitted by a red light emitting diode can range from 610nm to 670 nm. The dominant wavelength of the light emitted by the green light emitting diode may range from 510nm to 560 nm. The dominant wavelength of light emitted by a blue light emitting diode may range from 254nm to 470 nm. Those skilled in the art can adjust the number of light emitting elements in the first light emitting module 120 and the dominant wavelength range thereof according to design requirements, and the invention is not limited thereto. In some embodiments, the

light emitting elements

122a, 122b and 122c may be blue light emitting diodes, and at least two of the light channel structures 112 respectively corresponding to the

light emitting elements

122a, 122b and 122c may be covered with a wavelength conversion material, so that the light channel structures 112 can transmit light with different main wavelength ranges. For example, the light channel structure 112 corresponding to the light emitting element 122a may not be covered with the wavelength converting material, the light channel structure 112 corresponding to the light emitting element 122b may be covered with the wavelength converting material of red, and the light channel structure 112 corresponding to the light emitting element 122c may be covered with the wavelength converting material of green. In some embodiments, the wavelength conversion material described above may include fluorescent molecules, quantum dots, quantum rods, or a combination thereof.

Referring to fig. 1A and 1B, in some embodiments, the display device 10 may further include a gap filling material 124 and a first light recycling layer 126. The first light-emitting module 120, the gap filling material 124 and the first light recycling layer 126 are all adjacent to the same side of the light guide structure 110. In the present embodiment, the gap filling material 124 covers the first light emitting module 120. Specifically, the first light-emitting module 120 may be adjacent to the first end surface TS1 of the light channel structure 112 through the gap filling material 124. In other words, a portion of the gap filling material 124 may be located between the first light emitting module 120 and the light channel structure 112. In some embodiments, the material of the gap filling material 124 may include a photo-setting resin or a thermal setting resin. By providing the gap filling material 124, the first light emitting module 120 is prevented from being affected by moisture and oxygen in the environment, and the reliability of the first light emitting module 120 can be improved. In the present embodiment, the first light recycling layer 126 is disposed on the periphery of the gap filling material 124. Specifically, the first light recycling layer 126 may cover a portion of the first light emitting module 120, such that the surface of the first light emitting module 120 not facing the light guiding structure 110 may be covered by the first light recycling layer 126 and the reflective layer 114. As such, the light emitted by the first light-emitting module 120 can be effectively guided into the light guide structure 110. In some embodiments, the first light recycling layer 126 may extend from the first inner surface S1 of the first substrate 100 to the side of the light guiding structure 110 facing the second substrate 102. In other embodiments, the first light recycling layer 126 may extend from the first inner surface S1 of the first substrate 100 to the side of the light guiding structure 110 facing the second substrate 102, or may extend from the insulating protective layer 116 to the side of the light guiding structure 110. In some embodiments, the material of the first light recovery layer 126 may include aluminum, silver, titanium, gold, or a combination thereof.

In some embodiments, the display device 10 may further include a second light recycling layer 128, wherein the second light recycling layer 128 is disposed on a side of the light guiding structure 110 opposite to the first light emitting module 120. For example, the first light-emitting module 120 may be adjacent to the first end surface TS1 of the optical channel structure 112, and the second light recycling layer 128 may be adjacent to the second end surface TS2 of the optical channel structure 112. In some embodiments, the second light recycling layer 128 may be formed on the first inner surface S1 of the first substrate 100 and cover the second end TS2 of the light channel structure 112. In some embodiments, the material of the second light recovery layer 128 may include aluminum, silver, titanium, gold, or a combination thereof. By providing the second light recycling layer 128, light entering the environment from the light tunnel structure 112 via the second end face TS2 may be reflected back into the light tunnel structure 112.

In this embodiment, the display device 10 further includes an element array 130, wherein the element array 130 is disposed on the second substrate 102. In some embodiments, the element array 130 may be disposed on the second inner surface S2 of the second substrate 102. For example, the device array 130 may include pixel circuits, transparent electrodes, and signal lines (all omitted). The pixel circuit may include active and passive elements. The active element may comprise a transistor and the passive element may comprise a capacitor. Fig. 1A and 1B show the element array 130 only in a single-layer structure. However, the element array 130 may actually be a multilayer structure. For example, the multi-layer structure may include insulating layers and conductive patterns alternately stacked on each other. In this embodiment, the display device 10 further includes a liquid crystal switching layer 140, wherein the liquid crystal switching layer 140 is disposed between the light guide structure 110 and the second substrate 102. In other words, the liquid crystal switching layer 140 is sandwiched between the first inner surface S1 of the first substrate 100 and the second inner surface S2 of the second substrate 102. The liquid crystal switching layer 140 includes a plurality of liquid crystal molecules LC, and the liquid crystal molecules LC may have a birefringence characteristic. In other words, the rotation directions of the liquid crystal molecules LC of different regions of the liquid crystal switching layer 140 can be controlled by the element array 130, so that the liquid crystal switching layer 140 has two or more different refractive indexes. Specifically, the liquid crystal molecules LC are birefringent materials, i.e., have a long axis refractive index Ne in the long axis direction and a short axis refractive index No in the short axis direction. The light is modulated to form dark and light states through different refractive indexes (such as long axis refractive index Ne or short axis refractive index No) by different rotation directions of the liquid crystal molecules LC. As shown in fig. 1A, the long axis (also called optical axis) of the liquid crystal molecules LC is substantially parallel to the first inner surface S1 of the first substrate 100 (as shown in fig. 1A), and the short axis is substantially perpendicular to the first inner surface S1. When light passes through the liquid crystal switching layer 140, i.e. the light is going to enter the liquid crystal switching layer 140 from the light guide structure 110, total reflection is formed due to the difference between the refractive index of the light guide structure 110 and the short axis refractive index No of the liquid crystal molecules LC. Thus, most of the light does not penetrate the liquid crystal switching layer 140 and forms a dark state. As shown in fig. 1B, the long axis (also called optical axis) of the liquid crystal molecules LC is substantially perpendicular to the first inner surface S1. When light passes through the liquid crystal switching layer 140, i.e. the light is going to enter the liquid crystal switching layer 140 from the light guide structure 110, the light can be coupled into the liquid crystal switching layer 140 because the refractive index of the light guide structure 110 is substantially the same as the long-axis refractive index Ne of the liquid crystal molecules LC. In this way, most of the light can penetrate through the liquid crystal switching layer 140 to form a bright state. In some embodiments, the refractive index Ne of the liquid crystal molecules LC in the long axis is greater than the refractive index No in the short axis. In some embodiments, the difference between the long axis index of refraction Ne and the short axis index of refraction No may be greater than 0.1, or greater than 0.15. For example, the short axis refractive index No of the liquid crystal molecules LC may be 1.25 to 1.69. The long axis refractive index Ne of the liquid crystal molecules LC may be 1.4 to 1.7.

Furthermore, the material of the light guiding structure 110 may be selected to have a long axis refractive index Ne substantially equal to the liquid crystal molecules LC. In some embodiments, the difference between the refractive index of the light guiding structure 110 and the long axis refractive index Ne of the liquid crystal molecules LC may be less than 0.1. For example, the material of the light guide structure 110 may be transparent photoresist, glass, acrylic, and any plastic material including Polyethylene (PE), Polycarbonate (PC), acrylic (PMMA), and the material of the liquid crystal molecules LC may be positive or negative liquid crystal. Since the long axis refractive index Ne of the liquid crystal molecules LC is greater than the short axis refractive index No, the refractive index of the light guiding structure 110 is also greater than the short axis refractive index No of the liquid crystal molecules LC. In some embodiments, the difference between the refractive index of the light guide structure 110 and the short axis refractive index No of the liquid crystal molecules LC may be in a range of 0.1 to 0.3. As such, the liquid crystal molecules LC in some regions of the liquid crystal switching layer 140 are oriented as shown in fig. 1A, and the light from the first light emitting module 120 is totally reflected when traveling to the interface between the light guide structure 110 and the region of the liquid crystal switching layer 140, so that the light cannot enter the liquid crystal switching layer 140. In other words, when the liquid crystal molecules LC in some regions of the liquid crystal switching layer 140 rotate to a specific direction, the regions of the display device 10 exhibit a dark state. On the other hand, the liquid crystal molecules LC in some areas of the liquid crystal switching layer 140 are oriented as shown in fig. 1B, and the light originating from the first light emitting module 120 can smoothly pass through the second substrate 102 via the light guide structure 110 and this area of the liquid crystal switching layer 140 without total reflection between the light guide structure 110 and the liquid crystal switching layer 140. In other words, when the liquid crystal molecules LC in some regions of the liquid crystal switching layer 140 rotate to another specific direction, the regions of the display device 10 show a bright state.

In some embodiments, the display device 10 may further include a spacer structure BK, wherein the spacer structure BK is disposed between the first substrate 100 and the second substrate 102. In some embodiments, the number of the spacing structures BK may be plural. The liquid crystal switching layer 140 may be positioned in a space between the plurality of spacer structures BK. It follows that some spacer structures BK may be located within the liquid crystal switching layer 140. In some embodiments, the spacing structure BK may include a reflective material. In other embodiments, a reflective layer (not shown) may be formed on the surface of the spacer structure BK. In this way, light traveling from the liquid crystal switching layer 140 to both sides along a direction substantially parallel to the first substrate 100 and the second substrate 102 can be reflected back into the liquid crystal switching layer 140 by the spacer structure BK.

Referring to fig. 1A to fig. 1C, in some embodiments, the display device 10 may further include a pair of liquid crystal alignment layers, such as a first liquid crystal alignment layer 142a and a second liquid crystal alignment layer 142b, wherein the liquid crystal switching layer 140 is located between the first liquid crystal alignment layer 142a and the second liquid crystal alignment layer 142 b. In the present embodiment, the first liquid crystal alignment layer 142a may be disposed on the first inner surface S1 of the first substrate 100, and the second liquid crystal alignment layer 142b is disposed on the second inner surface S2 of the second substrate 102. In some embodiments, the first liquid crystal alignment layer 142a has a continuous structure in both the first direction D1 and the second direction D2. In other embodiments, the first liquid crystal alignment layer 142a is not continuous (not shown) in the second direction D2, but has a gap between adjacent light channel structures 112. This gap and the gap G between adjacent light tunnel structures 112 communicate with each other and may have the same or different widths. For example, the materials of the first and second liquid

crystal alignment layers

142a and 142b may respectively include diamond-like carbon (DLC), silicon carbide, silicon oxide, silicon nitride, aluminum oxide, cerium oxide, tin oxide, zinc titanate, polyimide, polyvinyl cinnamate (PVCN), Polymethacrylate (PMMA), or a combination thereof.

In some embodiments, the display device 10 may further include a pair of transparent electrodes respectively disposed on the first and second liquid

crystal alignment layers

142a and 142b at a side opposite to the liquid crystal switching layer 140. In some embodiments, the transparent electrode 144 of the pair of transparent electrodes may be located between the first liquid crystal alignment layer 142a and the light guide structure 110. In some embodiments, the transparent electrode 144 is not continuous in the second direction D2, but has gaps between adjacent light tunnel structures 112 (as shown in fig. 1C). This gap and the gap G between adjacent light tunnel structures 112 communicate with each other and may have the same or different widths. On the other hand, a transparent electrode (not shown) disposed on a side of the second liquid crystal alignment layer 142b opposite to the liquid crystal switching layer 140 may be integrated into the element array 130, or may be located between the element array 130 and the second liquid crystal alignment layer 142b (not shown). For example, the materials of the pair of transparent electrodes may respectively include Indium Tin Oxide (ITO), Aluminum Zinc Oxide (AZO), Indium Zinc Oxide (IZO), or a combination thereof. A pair of transparent electrodes on opposite sides of liquid crystal switching layer 140 may be configured to control the turning of liquid crystal molecules LC, thereby controlling the bright or dark state of different areas of display device 10. In some embodiments, the display device 10 may further include a sealant SL, wherein the sealant SL is disposed between the first substrate 100 and the second substrate 102. In some embodiments, the sealant SL may be disposed on a side of the light guide structure 110 facing the second substrate 102 and extend to the second liquid crystal alignment layer 142b, but the invention is not limited thereto. In addition, the sealant SL may be disposed at an edge region of the second substrate 102. Although fig. 1A and 1B only show a portion of the sealant SL, the sealant SL may actually surround the liquid crystal switching layer 140 to prevent the liquid crystal switching layer 140 from being affected by moisture and oxygen in the external environment. In some embodiments, the material of the sealant SL may include a photo-curing resin or a thermal curing resin.

Based on the above, in contrast to controlling the polarization direction of light to control the on and off of the display device, the embodiment of the invention can utilize the birefringence property of the liquid crystal switching layer 140 to control the total reflection path and the optical coupling path of light, so as to form the dark state and the bright state of the display device 10. Thus, it is not necessary to dispose polarizers on the two opposite sides of the liquid crystal switching layer 140, and it is not necessary to dispose color filters. Therefore, the light transmittance of the display device 10 can be greatly improved, i.e., the optical efficiency of the display device 10 can be improved. In addition, in the embodiment of the invention, the first light-emitting module 120 is disposed between the pair of substrates (i.e., between the first substrate 100 and the second substrate 102) of the display device 10, as compared with the backlight module disposed outside the pair of substrates of the display device. Thus, the thickness of the display device 10 can be further reduced.

Fig. 3 is a top view of the first substrate 100, the light guide structure 110, and the first light-emitting module 320 according to some embodiments of the invention.

Referring to fig. 2 and 3, the first substrate 100, the light guide structure 110 and the first light-emitting module 320 shown in fig. 3 are similar to the first substrate 100, the light guide structure 110 and the first light-emitting module 120 shown in fig. 2. The difference between the two is that the first light-emitting modules 320 shown in fig. 3 are respectively located at corresponding positions and adjacent to the light channel structures 112. For example, each of the first light-emitting modules 320 is located corresponding to and adjacent to the first end surface TS1 of each of the light channel structures 112. Each of the first light-emitting modules 320 may include a plurality of light-emitting devices, and the plurality of light-emitting devices are adjacent to the same light channel structure 112. For example, each of the first light emitting modules 320 may include a light emitting element 322a, a light emitting element 322b, and a light emitting element 322 c. Each light emitting element may comprise one or more light emitting diodes having the same dominant wavelength range. The light emitting diode may be an inorganic light emitting diode or an organic light emitting diode, and the size of the light emitting diode may range from 1 μm to 10000 μm. For example, light emitting device 322a may include one or more red light emitting diodes, light emitting device 322b may include one or more green light emitting diodes, and light emitting device 322c may include one or more blue light emitting diodes. The dominant wavelength of light emitted by a red light emitting diode can range from 610nm to 670 nm. The dominant wavelength of the light emitted by the green light emitting diode may range from 510nm to 560 nm. The dominant wavelength of light emitted by a blue light emitting diode may range from 254nm to 470 nm. Those skilled in the art can adjust the number of light emitting elements in the first light emitting module 320 and the dominant wavelength range thereof according to design requirements, and the invention is not limited thereto.

In the embodiment shown in fig. 3, the plurality of light emitting elements in the first light emitting module 320 can be controlled by a driving circuit (not shown), so that the first light emitting module 320 can emit light with different dominant wavelength ranges according to a specific timing. In other words, in some embodiments, the first light-emitting module 320 can emit only a single dominant wavelength range at a time, and can emit a plurality of lights with different dominant wavelength ranges over a period of time.

Fig. 4 is a top view of the first substrate 100, the light guide structure 110, the first light emitting module 120, and the second light emitting module 420 according to some embodiments of the present invention.

Referring to fig. 2 and 4, the embodiment shown in fig. 4 is similar to the embodiment shown in fig. 2. The difference between the two is that the display device shown in fig. 4 may further include a plurality of second light emitting modules 420 instead of the second light recycling layer 128 of fig. 2, wherein the plurality of second light emitting modules 420 are disposed on the first inner surface S1 of the first substrate 100. In addition, the plurality of second light emitting modules 420 and the plurality of first light emitting modules 120 are located at opposite sides of the light guide structure 110. Each of the second light emitting modules 420 may include a plurality of light emitting elements. For example, each of the second light emitting modules 420 may include a light emitting element 422a, a light emitting element 422b, and a light emitting element 422 c. In some embodiments, the

light emitting elements

422a, 422b and 422c of the second light emitting module 420 are respectively located at positions corresponding to and adjacent to the second end surface TS2 of the plurality of light channel structures 112, and the

light emitting elements

122a, 122b and 122c of the first light emitting module are respectively located at positions corresponding to and adjacent to the first end surface TS1 of the plurality of light channel structures 112. In some embodiments, each light emitting element of the second light emitting module 420 has a single dominant wavelength range. In such embodiments, each light emitting element may comprise one or more light emitting diodes having the same dominant wavelength range. The light emitting diode may be an inorganic light emitting diode or an organic light emitting diode, and the size of the light emitting diode may range from 1 μm to 10000 μm. For example, the light emitting device 422a may include one or more red light emitting diodes, the light emitting device 422b may include one or more green light emitting diodes, and the light emitting device 422c may include one or more blue light emitting diodes. The dominant wavelength of light emitted by a red light emitting diode can range from 610nm to 670 nm. The dominant wavelength of the light emitted by the green light emitting diode may range from 510nm to 560 nm. The dominant wavelength of light emitted by a blue light emitting diode may range from 254nm to 470 nm. Those skilled in the art can adjust the number of the light emitting elements in the second light emitting module 420 and the dominant wavelength range thereof according to design requirements, which is not limited by the invention.

In some embodiments, the first and second

light emitting modules

120 and 420 opposite each other have the same dominant wavelength range. In other words, the light emitting elements of the first light emitting module 120 and the second light emitting module 420 that are opposite to each other and have the same main wavelength range are respectively adjacent to the first end surface TS1 and the second end surface TS2 of the same light channel structure 112. For example, the light emitting elements 122a and 422a respectively including one or more red light diodes may be respectively located corresponding to and adjacent to the first end surface TS1 and the second end surface TS2 of the light channel structure 112. As such, the light entering the optical channel structure 112 from the first end surface TS1 and the second end surface TS2 of the optical channel structure 112 may have substantially the same wavelength range. In other words, the light emitting devices with the same wavelength are disposed on both end surfaces of the same light channel structure 112. In the present embodiment, the first light emitting module 120 and the second light emitting module 420 can be driven simultaneously or in a time-sharing manner.

Fig. 5 is a top view of the first substrate 100, the light guide structure 110, and the first light-emitting module 520 according to some embodiments of the invention.

Referring to fig. 2 and 5, the embodiment shown in fig. 5 is similar to the embodiment shown in fig. 2. The difference between the two is that each light emitting element of the first light emitting module 520 shown in fig. 5 is located at a position corresponding to and adjacent to one side of at least two light channel structures 112. For example, the first light emitting module 520 may include a light emitting element 522a, a light emitting element 522b and a light emitting element 522c, and the light emitting element 522a, the light emitting element 522b and the light emitting element 522c are respectively located at corresponding positions and adjacent to the first end surfaces TS1 of the three light channel structures 112. Each light emitting element may comprise one or more light emitting diodes having the same dominant wavelength range. The light emitting diode may be an inorganic light emitting diode or an organic light emitting diode, and the size of the light emitting diode may range from 100 μm to 10000 μm. For example, the light emitting element 522a may include one or more red light emitting diodes, the light emitting element 522b may include one or more green light emitting diodes, and the light emitting element 522c may include one or more blue light emitting diodes. The dominant wavelength of light emitted by a red light emitting diode can range from 610nm to 670 nm. The dominant wavelength of the light emitted by the green light emitting diode may range from 510nm to 560 nm. The dominant wavelength of light emitted by a blue light emitting diode may range from 254nm to 470 nm. Those skilled in the art can adjust the number of the light emitting elements in the first light emitting module 520 and the dominant wavelength range thereof according to design requirements, and the invention is not limited thereto.

In some embodiments, the

light emitting elements

522a, 522b and 522c may be blue light emitting diodes, and at least two groups of the light channel structures 112 corresponding to the

light emitting elements

522a, 522b and 522c may be covered with a wavelength conversion material, so that the light channel structures 112 of the groups can transmit light in different main wavelength ranges. For example, a set of light channel structures 112 corresponding to light emitting element 522a may not be covered with wavelength converting material, a set of light channel structures 112 corresponding to light emitting element 522b may be covered with wavelength converting material of red, and a set of light channel structures 112 corresponding to light emitting element 522c may be covered with wavelength converting material of green. In some embodiments, the wavelength conversion material described above may include fluorescent molecules, quantum dots, quantum rods, or a combination thereof.

Fig. 6 is a top view of the first substrate 100, the light guide structure 110, and the first light emitting module 620 according to some embodiments of the present invention.

Referring to fig. 5 and 6, the embodiment shown in fig. 6 is similar to the embodiment shown in fig. 5. The difference between the two is that the light emitting elements of each of the first light emitting modules 620 shown in fig. 6 are located correspondingly and adjacent to one side of the same light channel structures 112. For example, each of the first light-emitting modules 620 may include a light-emitting element 622a, a light-emitting element 622b and a light-emitting element 622c, and the light-emitting

elements

622a, 622b and 622c are located correspondingly and adjacent to the first end surfaces TS1 of the three light channel structures 112. Each light emitting element may comprise one or more light emitting diodes having the same dominant wavelength range. The light emitting diode may be an inorganic light emitting diode or an organic light emitting diode, and the size of the light emitting diode may range from 100 μm to 10000 μm. For example, the light emitting element 622a may include one or more red light emitting diodes, the light emitting element 622b may include one or more green light emitting diodes, and the light emitting element 622c may include one or more blue light emitting diodes. The dominant wavelength of light emitted by a red light emitting diode can range from 610nm to 670 nm. The dominant wavelength of the light emitted by the green light emitting diode may range from 510nm to 560 nm. The dominant wavelength of light emitted by a blue light emitting diode may range from 254nm to 470 nm. Those skilled in the art can adjust the number of light emitting elements in the first light emitting module 620 and the dominant wavelength range thereof according to design requirements, and the invention is not limited thereto.

In the embodiment shown in fig. 6, the plurality of light emitting elements in the first light emitting module 620 can be controlled by a driving circuit (not shown), so that the first light emitting module 620 can emit light with different dominant wavelength ranges according to a specific timing. In other words, in some embodiments, the first light-emitting module 620 can emit only a single dominant wavelength range at a time, and can emit a plurality of lights with different dominant wavelength ranges at different times.

Fig. 7 is a top view of the first substrate 100, the light guide structure 710, and the first light emitting module 720 according to some embodiments of the invention.

Referring to fig. 5 and 7, the embodiment shown in fig. 7 is similar to the embodiment shown in fig. 5. The difference between the two is that the light emitting elements of each of the first light emitting modules 720 shown in fig. 7 are alternately disposed on two opposite sides of the light guide structure 710 along the second direction D2. In addition, the plurality of light channel structures of the light guide structure 710 are alternately shifted toward the first direction D1 (e.g., the forward and reverse directions of the first direction D1) opposite to each other along the second direction D2. The plurality of light tunnel structures may be divided into light tunnel structures 712a and light tunnel structures 712b based on the offset direction of the light tunnel structures. Specifically, in the embodiment of fig. 7, every two adjacent

light channel structures

712a and 712b have an offset DV in the first direction D1. For example, each of the first light emitting modules 720 may include a light emitting element 722a, a light emitting element 722b and a light emitting element 722c arranged in sequence along the second direction D2. The light emitting device 722a, the light emitting device 722b and the light emitting device 722c are respectively located at corresponding positions and adjacent to the two light channel structures. In some embodiments, the

light emitting elements

722a and 722c are respectively located corresponding to and adjacent to the first end surfaces TS1 of the two light channel structures 712a, and the light emitting element 722b is located corresponding to and adjacent to the second end surfaces TS2 of the two light channel structures 712 b. Each light emitting element may comprise one or more light emitting diodes having the same dominant wavelength range. The light emitting diode may be an inorganic light emitting diode or an organic light emitting diode, and the size of the light emitting diode may range from 100 μm to 10000 μm. For example, the light emitting device 722a may include one or more red light emitting diodes, the light emitting device 722b may include one or more green light emitting diodes, and the light emitting device 722c may include one or more blue light emitting diodes. The dominant wavelength of light emitted by a red light emitting diode can range from 610nm to 670 nm. The dominant wavelength of the light emitted by the green light emitting diode may range from 510nm to 560 nm. The dominant wavelength of light emitted by a blue light emitting diode may range from 254nm to 470 nm. Those skilled in the art can adjust the number of light emitting elements in the first light emitting module 720 and the dominant wavelength range thereof according to design requirements, which the invention is not limited to. In another modified embodiment, a second recycling layer may be disposed at a suitable position of the light channel (e.g., corresponding to the other end surface of the light emitting device) according to different requirements, so as to improve the light utilization rate and the brightness.

In summary, compared with controlling the polarization direction of light to control the on and off of the display device, the embodiment of the invention can control the total reflection path and the optical coupling path of light by using the birefringence characteristic of the liquid crystal switching layer to form the dark state and the bright state of the display device. Therefore, the polarizer and the color filter do not need to be arranged on the two opposite sides of the liquid crystal switching layer. Therefore, the light transmittance of the display device can be greatly improved. In other words, the optical efficiency of the display device can be improved. In addition, in contrast to disposing the backlight module outside the pair of substrates of the display device, the first light-emitting module is disposed between the pair of substrates (i.e., between the first substrate and the second substrate) of the display device according to the embodiment of the invention. Thus, the thickness of the display device can be further reduced.

Although the present invention has been described with reference to the above embodiments, it should be understood that various changes and modifications can be made therein by those skilled in the art without departing from the spirit and scope of the invention.

Claims

1. A display device, comprising:

a first substrate and a second substrate, wherein the first substrate has an inner surface facing the second substrate;

a light guide structure disposed on the inner surface of the first substrate;

the first light-emitting module is arranged on the inner surface and is adjacent to one side of the light guide structure;

an element array disposed on the second substrate; and

a liquid crystal switching layer disposed between the light guide structure and the second substrate;

the light guide structure comprises a plurality of light channel structures, the light channel structures are arranged along a second direction and extend along a first direction, and a gap is formed between every two adjacent light channel structures;

when one light channel structure corresponds to a plurality of light-emitting elements, the light-emitting modules formed by the light-emitting elements only emit light in a single dominant wavelength range at the same time.

2. The display device of claim 1, further comprising:

a gap filling material, which coats the first light-emitting module and is adjacent to the side of the light guide structure; and

a first light recycling layer disposed on the periphery of the gap filling material.

3. The display device of claim 1, further comprising:

and the second light recovery layer is arranged on the other side of the light guide structure.

4. The display device of claim 1, further comprising:

a second light emitting module disposed on the inner surface of the first substrate, wherein the first light emitting module and the second light emitting module are disposed at opposite sides of the light guide structure, and a dominant wavelength range of the first light emitting module is substantially equal to a dominant wavelength range of the second light emitting module.

5. The display device of claim 1, further comprising:

and a spacing structure disposed between the first substrate and the second substrate and in the liquid crystal switching layer, wherein the spacing structure comprises a reflective material.

6. The display device according to claim 1, wherein each of the light emitting elements is positioned corresponding to and adjacent to each of the light channel structures.

7. The display device according to claim 1, wherein each of the light-emitting elements is positioned corresponding to and adjacent to one of the at least two light channel structures.

8. The display device of claim 1, wherein the first light module comprises a plurality of light emitting elements, and the light emitting elements are positioned corresponding to and adjacent to the light channel structures.

9. A display device, comprising:

a first substrate having a first inner surface and a second substrate having a second inner surface, the first inner surface

The second inner surfaces facing each other;

a light guide structure disposed on the first inner surface and including a plurality of light channel structures arranged along a second direction and extending along a first direction, and a gap is formed between two adjacent light channel structures, wherein each light channel structure has a first end surface and a second end surface opposite to each other, and the refractive index of the material of the light guide structure is 1.4 to 1.7;

a light emitting module disposed on the first inner surface, the light emitting module corresponding to the first end surfaces of the light channel structures, the light emitting module including a plurality of light emitting elements, each light emitting element having a single dominant wavelength range, one light channel structure corresponding to one or more light emitting elements, and the light emitting module composed of the light emitting elements emitting light of only the single dominant wavelength range at the same time when the one light channel structure corresponds to the plurality of light emitting elements;

an element array disposed on the second substrate; and

and the liquid crystal switching layer is clamped between the first inner surface of the first substrate and the second inner surface of the second substrate.

10. The display device of claim 9, wherein the material of the light guide structure has a visible light transmittance of 20% to 99%.

11. The display device according to claim 9, wherein the light emitting module comprises a plurality of light emitting elements, each of the light channel structures corresponds in position to each of the light emitting elements, or at least two of the light channel structures correspond in position to each of the light emitting elements.

12. The display device of claim 9, further comprising:

a reflective layer disposed on the first inner surface and between the first substrate and the light guide structure; and

an insulating protection layer disposed between the reflection layer and the light guide structure.

13. The display device according to claim 9, wherein the thickness and the width of each of the light channel structures are 10 μm to 500 μm and 1 μm to 200 μm, respectively, and a distance is formed between two adjacent light channel structures, and the distance is 1 μm to 100 μm.