Display device

Abstract

The application discloses a display device, comprising a display panel, a first adhesive layer, a diffusion layer and an anti-glare film. The first adhesive layer is arranged on the display panel, and the first adhesive layer is arranged between the display panel and the diffusion layer. The anti-glare film is arranged on the diffusion layer, wherein the thickness of the diffusion layer is greater than or equal to 15 microns.

Description

Technical Field

[0001] This invention relates to an electronic device, and more particularly to a display device. Background Technology

[0002] As display device technology continues to improve, the market demands higher and higher display quality. As a result, the number of various optical films (such as anti-reflective films, diffusion films, brightness enhancement films, etc.) is gradually increasing in display devices to solve various technical problems such as uniform light output and anti-reflective light.

[0003] However, as display devices incorporate more and more optical films, the unexpected reflections, diffusions, refractions, and interferences generated between these multiple layers become increasingly complex and severe. The light diffusion structure on the surface of the anti-glare film can also cause uneven distribution of light intensity on the display screen, exacerbating screen flicker and gradually affecting display quality or causing viewing discomfort. How to ensure that multiple optical films function effectively while reducing screen flicker remains a challenge for manufacturers. Summary of the Invention

[0004] This invention provides a display device that, while having good anti-glare properties, can also effectively reduce screen flicker and provide a better display effect.

[0005] In one embodiment of the present invention, the display device includes a display panel, a first adhesive layer, a diffusion layer, and an anti-glare film. The first adhesive layer is disposed on the display panel and between the display panel and the diffusion layer. The anti-glare film is disposed on the diffusion layer, wherein the thickness of the diffusion layer is greater than or equal to 15 micrometers.

[0006] Based on the above, in the display device of the present invention, by disposing a diffusion layer between the first adhesive layer and the anti-glare film, and controlling the thickness of the diffusion layer to be greater than or equal to 15 micrometers, optical interference generated between the anti-glare film and the other film layers can be effectively reduced, further reducing the flicker of the displayed image, and the anti-glare film can also maintain its anti-reflective function. The display device of the present invention can provide a good display image, and has a good viewing experience in environments with excessively strong or dim natural light, as well as at the front or side viewing angles of the display device.

[0007] To make the above features and advantages of the present invention more apparent and understandable, specific embodiments are described below in conjunction with the accompanying drawings. Attached Figure Description

[0008] Figure 1A This is a cross-sectional schematic diagram of a display device according to a first embodiment of the present invention.

[0009] Figure 1B This is a comparative schematic diagram of various modified embodiments of the display device of the first embodiment.

[0010] Figure 1C as well as Figure 1D This is a comparative schematic diagram of various modified embodiments of the display device of the first embodiment.

[0011] Figure 2 This is a cross-sectional schematic diagram of a display device according to a second embodiment of the present invention.

[0012] Figure 3 This is a cross-sectional schematic diagram of a display device according to a third embodiment of the present invention.

[0013] In the attached figures, the following labels are used:

[0014] 10, 10A, 10B, 10C, 10D, 10E, 20, 30: Display devices

[0015] 100: Display panel

[0016] 100A, 132A: Surface

[0017] 110: First adhesive layer

[0018] 120: Diffusion layer

[0019] 130: Anti-glare film

[0020] 131: First material layer

[0021] 132: Second material layer

[0022] 140: Substrate

[0023] 150: Second adhesive layer

[0024] D1, D2, D31, D32, D4, D5: Thickness

[0025] X, Y: Direction Detailed Implementation

[0026] As used herein, “about,” “approximately,” “essentially,” or “substantially” includes the value and the average value within an acceptable range of deviations from a particular value as determined by one of ordinary skill in the art, taking into account the measurement in question and a particular number of errors associated with the measurement (i.e., limitations of the measurement system). For example, “about” may mean within one or more standard deviations of the value, or, for example, within ±30%, ±20%, ±15%, ±10%, ±5%. Furthermore, the use of “about,” “approximately,” “essentially,” or “substantially” herein may be chosen to select a more acceptable range of deviations or standard deviations depending on the nature of the measurement, the cutting nature, or other properties, and a single standard deviation may not be applicable to all properties.

[0027] In the accompanying drawings, the thicknesses of layers, films, panels, regions, etc., are enlarged for clarity. It should be understood that when an element such as a layer, film, region, or substrate is referred to as being "on" or "connected" to another element, it may be directly on or connected to the other element, or intermediate elements may also be present. Conversely, when an element is referred to as being "directly on" or "directly connected" to another element, no intermediate elements are present. As used herein, "connection" can refer to physical and / or electrical connections.

[0028] The invention will now be described in detail with reference to exemplary embodiments thereof, examples of which are illustrated in the accompanying drawings. Wherever possible, the same element symbols are used in the drawings and description to denote the same or similar parts.

[0029] Figure 1A This is a cross-sectional schematic diagram of a display device according to a first embodiment of the present invention. Please refer to... Figure 1A The display device 10 includes a display panel 100, a first adhesive layer 110, a diffusion layer 120, and an anti-glare film 130. The first adhesive layer 110 is disposed on the display panel 100. More specifically, the first adhesive layer 110 is disposed between the display panel 100 and the diffusion layer 120. The anti-glare film 130 is disposed on the diffusion layer 120.

[0030] In this embodiment, the display panel 100 may be a self-emissive display panel, for example, to provide display light to form a display image. The pixels of the self-emissive display panel may include, for example, organic light-emitting diodes (OLEDs) or micro light-emitting diodes (μLEDs), but the invention is not limited thereto. In other embodiments, the display panel 100 may also be a non-self-emissive display panel, such as a liquid crystal display (LCD), and the light source may be, for example, a sub-millimeter light-emitting diode (mini-LED) or a light-emitting diode (LED), but the invention is not limited thereto.

[0031] The first adhesive layer 110 can be, for example, an optically clear adhesive (OCA). It is applied to the surface 100A of the display panel 100 in a direction (e.g., direction X) to allow the diffusion layer 120 to adhere to the surface 100A of the display panel 100 via the first adhesive layer 110. Finally, the optically clear adhesive is cured. In some embodiments, the visible light transmittance of the first adhesive layer 110 can be greater than or equal to 99%, but the invention is not limited thereto. In some embodiments, the first adhesive layer 110 can also be a solid adhesive substrate. For example, the first adhesive layer 110 can be a plastic substrate (e.g., a PET film). In the Y direction, the opposite sides of the first adhesive layer 110 have a UV-curable adhesive or a thermosetting adhesive to adhere one side of the diffusion layer 120 and the surface 100A of the display panel 100, respectively. Solid adhesives require less consideration of adhesion issues and offer better process margins when each film layer needs to be cut and manufactured; however, the invention is not limited thereto.

[0032] It is worth mentioning that the first adhesive layer 110 can directly contact the display panel 100. In other words, the first adhesive layer 110 can be directly disposed outside the components of the display panel 100 and in contact with the surface 100A of the display panel 100 (i.e., the display surface of the display panel 100), so that there are no air gaps or bubbles between the display panel 100 and the first adhesive layer 110. This can reduce the probability of unexpected refraction, reflection, or interference of display light at the interface between different film layers, thereby further reducing interference factors that may generate flicker.

[0033] The diffusion layer 120 may be, for example, a solid optical diffuser sheet with high transmittance to visible light and appropriate haze, but the invention is not limited thereto. In some embodiments, the diffusion layer 120 may be a diffusing optically clear adhesive (DOCA) with good visible light transmittance (e.g., greater than 90%) and appropriate adhesion. More specifically, the diffusion layer 120 may be the same optically clear adhesive material as the aforementioned first adhesive layer 110, and may include a plurality of optically diffusing particles uniformly dispersed therein. The diffusion optically clear adhesive is coated and hardened in the surface direction (e.g., direction X) of the display device 10, but the invention is not limited thereto. When the adhesive portion of the diffusion layer 120 and the first adhesive layer 110 are made of the same material, the chance of unexpected refraction, reflection, and interference of the display beam of the display panel 100 between different material layers can be reduced, thereby reducing the probability of stray light generation and improving display quality.

[0034] The anti-glare film 130 may further include a first material layer 131 and a second material layer 132, which together constitute the anti-glare film 130. For example, the first material layer 131 may be a PET film with a certain thickness D31, such as greater than or equal to 80 micrometers and less than or equal to 100 micrometers; while the second material layer 132 may be a hardened transparent plastic film, which is then subjected to a surface atomization treatment. This causes the second material layer 132 to scatter the external light beam when it shines from outside the display device 10, thereby further reducing the specular reflection of the light beam on the surface 132A of the second material layer 132, thus achieving an anti-glare effect. The thickness D32 of the second material layer 132 is approximately greater than or equal to 4 micrometers and less than or equal to 5 micrometers. In some embodiments, the second material layer 132 may be other anti-reflective materials. The present invention is not limited thereto.

[0035] In some embodiments, the first material layer 131 and the second material layer 132 of the anti-glare film 130 may be composed of the same material. Specifically, a PET film constituting the anti-glare film 130 may be prepared, and a surface atomization treatment may be directly performed on the surface of the PET film on the side opposite to the display device 10 to obtain the second material layer 132 and the first material layer 131 that has not undergone atomization treatment. In some embodiments, the surface 132A of the second material layer 132 may have multiple irregular and uneven optical microstructures to achieve the function of eliminating natural reflected light.

[0036] It is worth mentioning that, in the embodiments of the present invention, the screen flicker of the display device 10 can be reduced by ensuring that the thickness D2 of the diffusion layer 120 is greater than or equal to 15 micrometers (μm). Specifically, if the thickness D2 of the diffusion layer 120 is not thick enough, even if the haze of the diffusion layer 120 is increased, the effect on reducing screen flicker is still limited. However, in the embodiments of the present invention, when the thickness D2 of the diffusion layer 120 is greater than or equal to 15 μm, for example, D2 is actually 50 μm, and the diffusion layer 120 is attached to the display panel 100 via the first adhesive layer 110, the diffusion layer 120 has the effect of reducing screen flicker.

[0037] On the other hand, if the thickness D2 of the diffusion layer 120 is too thick, in addition to potentially reducing the resolution of the displayed image, the display device 10 is also prone to white, hazy reflections from external light at various viewing angles, affecting the viewing experience of the display device 10. Specifically, the thickness D2 of the diffusion layer 120 can be less than or equal to 120 μm. This achieves the function of reducing flicker while also avoiding the influence of stray light formed by external reflections.

[0038] Although not shown, in some embodiments, the display device 10 may also include other film layers. For example, a waterproof barrier layer or protective cover may be further provided on one surface of the anti-glare film 130 (e.g., surface 132A) to further increase the device reliability and strength of the display device 10. The invention is not limited thereto.

[0039] The following are some other embodiments to illustrate the present invention in detail, wherein the same components will be marked with the same symbols, and the description of the same technical content will be omitted. For the omitted parts, please refer to the foregoing embodiments, and they will not be repeated below.

[0040] Figure 1B This is a comparative schematic diagram of various modified embodiments of the display device of the first embodiment. Please refer to... Figure 1B Display devices 10A, 10B, and 10C are modified embodiments of the aforementioned display device 10. Specifically, the thickness D1 of the first adhesive layer 110 of display devices 10A, 10B, and 10C is substantially 125 μm; the thickness D2 of the diffusion layer 120 is substantially 50 μm; and the total thickness of the two layers (i.e., the sum of the thickness D1 of the first adhesive layer 110 and the thickness D2 of the diffusion layer 120) is 175 μm. The thickness D31 of the first material layer 131 of the anti-glare film 130 is substantially 80 μm; and the thickness D32 of the second material layer 132 is substantially 5 μm. The difference between these modified embodiments and display device 10 lies in the haze value of the diffusion layer 120. Specifically, the haze value of the diffusion layer 120 of the display device 10A is about 70%; the haze value of the diffusion layer 120 of the display device 10B is about 80%; and the haze value of the diffusion layer 120 of the display device 10C is about 90%.

[0041] Depend on Figure 1B The comparison shows that the higher the haze value of the diffusion layer 120, for example, above 70%, the better the effect on reducing flicker (e.g., all achieve an anti-flicker level of 3 or higher, reaching an acceptable level, and further achieving an anti-flicker level of 4 or higher, reaching a good or even excellent level). However, the present invention is not limited to this. In other embodiments, the haze of the diffusion layer 120 can also be below 70% (e.g., substantially around 30%), which can also achieve an acceptable anti-flicker effect (e.g., an anti-flicker level of approximately 3-). The flicker level can be detected by a flash point tester (e.g., DM&S SMS-1000) or other detection devices, and the present invention is not limited to this.

[0042] On the other hand, it has been verified that the thickness D1 of the first adhesive layer 110 also affects the flicker resistance of the display device 10. For example, under the same conditions, changing only the thickness D1 of the first adhesive layer 110 shows that the flicker resistance of the display device 10 gradually increases with the increase of the thickness D1. Specifically, in some embodiments, when the thickness D1 of the first adhesive layer 110 is 100 micrometers or more, the flicker resistance of the display device 10 can reach an acceptable level of approximately 3. In some embodiments, the thickness D1 of the first adhesive layer 110 can be substantially 125 micrometers, and the present invention is not limited thereto.

[0043] Figure 1C as well as Figure 1D This is a comparative schematic diagram of various modified embodiments of the display device of the first embodiment. Please refer to... Figure 1C as well as Figure 1D The display devices 10C and 10D of this embodiment are similar to the aforementioned display device 10, except that the haze value and placement position of the diffusion layer 120 are different. For example, the haze value of the diffusion layer 120 of the display device 10C can be approximately 30%. The haze value of the diffusion layer 120 of the display device 10D is also approximately 30%, but the diffusion layer 120 of the display device 10D is disposed between the first adhesive layer 110 and the display panel 100, and contacts the surface 100A of the display panel 100 and the first adhesive layer 110 on opposite sides in the Y direction (i.e., the thickness direction of the display device 10D) via the diffusion layer 120.

[0044] Testing revealed that the flicker reduction effect of the diffusion layer 120 in display device 10D is relatively poor, for example, around flicker resistance level 2. Display device 10C, on the other hand, achieves a better flicker resistance level, for example, around flicker resistance level 3, reaching an acceptable level. Similarly, as mentioned above, a thicker D1 of the first adhesive layer 110 beneath the diffusion layer 120 is more beneficial for increasing the flicker resistance of display device 10C.

[0045] Figure 2 This is a cross-sectional schematic diagram of a display device according to a second embodiment of the present invention. Please refer to... Figure 2 The display device 20 is similar to the aforementioned display device 10, except that the two side films of the first adhesive layer are different. Specifically, the display device 20 further includes a substrate 140 disposed between the first adhesive layer 110 and the diffusion layer 120. The material of the substrate 140 includes polyethylene terephthalate (PET), cellulose triacetate (TAC), optical grade polymethyl methacrylate (PMMA), or polycarbonate (PC), and the first adhesive layer 110 can be the aforementioned optically transparent adhesive.

[0046] Specifically, the display device 20 can be constructed by coating a first adhesive layer 110 onto a solid substrate 140 and attaching the substrate 140 to the surface 100A of the display panel 100 via the first adhesive layer 110. This invention is not limited to this. In some embodiments, the first adhesive layer 110 and the substrate 140 can be made of the same material to reduce unexpected light beam refraction, reflection, or interference between different interfaces. Alternatively, the adhesive layer between the display panel 100 and the diffusion layer 120 in the display device 20 can be a composite material composed of the first adhesive layer 110 and the substrate 140. Similar to the aforementioned, the solid substrate 140 requires less concern about adhesive adhesion and has better process margins when each film layer needs to be cut and manufactured, increasing the process feasibility of the display device 20.

[0047] On the other hand, the substrate 140 may have a suitable thickness D4, and the thickness D4 may be greater than or equal to 40 μm; while the thickness D1 of the first adhesive layer 110 may be substantially 50 μm. Thus, the sum of the thickness D4 and the thickness D1 in this embodiment can be similar to the thickness D1 of each of the first adhesive layers 110 in the aforementioned embodiments, and the optical effect of the aforementioned display device 10 can also be achieved, which will not be elaborated here.

[0048] Figure 3 This is a cross-sectional schematic diagram of a display device according to a third embodiment of the present invention. Please refer to... Figure 3 The display device 30 is similar to the aforementioned display device 10, except that the thickness of the diffusion layer 120 and the types of each film layer are different.

[0049] In detail, the thickness D2 of the diffusion layer 120 of the display device 30 can be greater than or equal to 120 micrometers. This can improve the anti-flicker effect of the display device 30. In order to reduce the visual interference problem caused by the formation of white haze-like reflected light due to the excessive thickness D2 of the aforementioned diffusion layer 120, the display device 30 also includes a second adhesive layer 150, which is disposed between the anti-glare film 130 and the diffusion layer 120, so that the diffusion layer 120 and the first material layer 131 of the anti-glare film 130 are respectively contacted and adhered by the opposite sides of the second adhesive layer 150 (e.g., the opposite sides in the Y direction). It is worth mentioning that, in addition to using the same adhesive material as the aforementioned first adhesive layer 110 to avoid unexpected refraction, reflection or interference phenomena affecting the display quality, the second adhesive layer 150 may also include a plurality of light-absorbing materials uniformly distributed in the second adhesive layer 150.

[0050] For example, the second adhesive layer 150 can be a black optically clear adhesive (BOCA), and the multiple light-absorbing materials can be, for example, graphite or dark dyes, etc., but the invention is not limited thereto. By utilizing the light-absorbing materials dispersed in the black optically clear adhesive, some of the light from the outside world is absorbed, thereby reducing the generation of hazy reflected light and improving the visual experience. In some embodiments, the second adhesive layer 150 as a whole can have an appropriate visible light absorption rate, for example, the absorption rate of the second adhesive layer 150 in the visible light band can be greater than or equal to 40%. While achieving the function of absorbing stray light, it will not absorb too much display light, thus avoiding problems such as excessively dim display light. On the other hand, the second adhesive layer 150 can have an appropriate thickness D5. For example, the value of the thickness D5 can be greater than or equal to 15 μm, such as substantially 50 μm, to achieve a better effect in absorbing stray light.

[0051] In summary, in the display device of the present invention, by disposing a diffusion layer between the first adhesive layer and the anti-glare film, and controlling the thickness of the diffusion layer to be greater than or equal to 15 micrometers, optical interference between the anti-glare film and the other film layers can be effectively reduced, further reducing the flicker of the displayed image, and the anti-glare film can also maintain its anti-reflective function. The display device of the present invention can provide a good display image, and has a good viewing experience in environments with excessively strong or dim natural light, as well as at both the front and side viewing angles of the display device.

[0052] Of course, the present invention may have other various embodiments. Without departing from the spirit and essence of the present invention, those skilled in the art can make various corresponding changes and modifications according to the present invention, but these corresponding changes and modifications should all fall within the protection scope of the appended claims.

Claims

1. A display device, characterized in that, include: Display panel; The first adhesive layer is disposed on the display panel; A diffusion layer, wherein the first adhesive layer is disposed between the display panel and the diffusion layer; An anti-glare film is disposed on the diffusion layer; A second adhesive layer is disposed between the anti-glare film and the diffusion layer, wherein the second adhesive layer includes a plurality of light-absorbing materials uniformly distributed, and the second adhesive layer is a black optically transparent adhesive. as well as A substrate is disposed between the first adhesive layer and the diffusion layer. The material of the substrate includes polyethylene terephthalate. The first adhesive layer is an optically transparent adhesive, and the first adhesive layer and the substrate can be made of the same material. The thickness of the diffusion layer is greater than or equal to 120 micrometers.

2. The display device as claimed in claim 1, characterized in that, The haze of the diffusion layer is greater than or equal to 70%.

3. The display device as claimed in claim 1, characterized in that, The thickness of the first adhesive layer is greater than or equal to 100 micrometers.

4. The display device as claimed in claim 1, characterized in that, The thickness of the substrate is greater than or equal to 40 micrometers, and the thickness of the first adhesive layer is actually 50 micrometers.

5. The display device as claimed in claim 1, characterized in that, These multiple light-absorbing materials are graphite or dark dyes.

6. The display device as claimed in claim 5, characterized in that, The thickness of the second adhesive layer is greater than or equal to 15 micrometers.

7. The display device as claimed in claim 5, characterized in that, The visible light transmittance of the second adhesive layer is greater than or equal to 40%.

8. The display device as claimed in claim 1, characterized in that, The anti-glare film has multiple optical microstructures on the side away from the display panel.

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