WO2024001421A1

WO2024001421A1 - Display apparatus

Info

Publication number: WO2024001421A1
Application number: PCT/CN2023/087925
Authority: WO
Inventors: 汪文强
Original assignee: 武汉华星光电半导体显示技术有限公司
Priority date: 2022-07-01
Filing date: 2023-04-12
Publication date: 2024-01-04
Also published as: CN115132084A; CN115132084B

Abstract

Provided is a display apparatus, comprising a flexible display module (40); a cover plate (60), which is arranged on one side of the flexible display module; a gas medium layer (70), which is filled between the flexible display module (40) and the cover plate (60); and a first anti-reflection layer (80), which is arranged on the surface of the flexible display module (40) that is close to the gas medium layer (70). The refractive index of the first anti-reflection layer (80) is greater than the refractive index of the gas medium layer (70).

Description

display device

Technical field

The present application relates to the field of display technology, and in particular, to a display device.

Background technique

As a new generation hub for human-computer interaction, organic light-emitting diode (OLED) displays play a pivotal role in providing consumers with timely information and improving visual experience. In recent years, after experiencing a new round of iterative updates of full-screen mobile phone applications with high screen-to-body ratios, the screens used by major mainstream terminal brands in the industry have exceeded 85%. High screen-to-body ratio displays have always been one of the key research points of major mobile phone and tablet terminal manufacturers. As consumers' requirements for screens have increased, terminal products such as waterfall screens and four-sided curved screens have appeared in recent years. In order to ensure that the front camera can achieve the camera function through the screen display area, a hole needs to be punched in the screen for light to pass through, and a true full-screen display cannot be achieved.

In response to the demand for improved screen-to-body ratio display and dual-layer front-facing shooting functions, a known under-screen camera display device uses a sliding movement of a flexible OLED display under the cover to hide the camera under the screen and Expand the shooting function. This design method avoids the design flaw of setting up a camera light-transmitting hole on the screen, and can take into account the two functions of full-screen display and front-facing photography at the same time.

However, in this type of display device, glare can be observed by the human eye when the screen is turned off, and the screen surface is reflective and white, which has become an urgent problem to be solved.

technical problem

In view of this, the present application provides a display device that can reduce glare when the screen is turned off.

Technical solutions

This application provides a display device, which includes:

Flexible display module, including light emitting surface;

A cover plate, arranged on the light-emitting surface of the flexible display module;

A gas dielectric layer filled between the flexible display module and the cover; and

A first anti-reflective layer, disposed on the surface of the flexible display module close to the gas medium layer, The refractive index of the first anti-reflection layer is greater than the refractive index of the gas medium layer.

Optionally, in one implementation, the display device further includes:

The middle frame includes a bottom plate and side walls provided on the bottom plate;

The scroll mechanism is rotatably installed in the middle frame and located at one end of the middle frame; and

A photosensitive element is arranged in the middle frame and located at the other end of the middle frame;

Wherein, the flexible display module is arranged on the scroll mechanism, and the flexible display module includes a connected first part and a second part. The first part is located on a side of the scroll mechanism close to the bottom plate and The second part is connected to the middle frame through a pretensioning mechanism provided on the bottom plate. The second part is located on the side of the scroll mechanism away from the bottom plate. The flexible display module is configured to be able to move relative to the middle frame. The frame reciprocates to expose or block the photosensitive element.

Optionally, in one embodiment, the flexible display module includes a flexible display panel and a protective layer disposed on a side of the flexible display panel close to the cover plate, and the refractive index of the protective layer is greater than the The refractive index of the first anti-reflective layer.

Optionally, in one embodiment, the refractive index of the first anti-reflection layer is n ₁ , the refractive index of the gas medium layer is n ₀ , and the refractive index of the protective layer is n _i , n ₀ , n _i and n _i satisfy the following formula:

Optionally, in one embodiment, the thickness of the first anti-reflection layer is h ₁ , the wavelength of the first incident light is λ ₁ , and the refractive index of the first anti-reflection layer is n ₁ , h ₁ , λ ₁ and n ₁ satisfy the following formula:
h ₁ =(1±30%)*(λ ₁ /4n ₁ )

Among them, λ ₁ is selected from any one of 550 nanometers, 620 nanometers to 760 nanometers, or 577 nanometers to 597 nanometers.

Optionally, in one embodiment, the refractive index of the protective layer is 2.0 to 2.1, the gas medium layer is an air layer, the thickness of the air layer ranges from 0.1 mm to 0.2 mm, and the first The refractive index of the anti-reflective layer ranges from 1.2 to 1.45.

Optionally, in one embodiment, the display device further includes a second anti-reflective layer, the second anti-reflective layer is disposed on a surface of the cover plate away from the flexible display module, and the third anti-reflective layer The refractive index of the secondary anti-reflective layer is greater than the refractive index of air.

Optionally, in one embodiment, the refractive index of the cover plate is greater than the refractive index of the second anti-reflection layer.

Optionally, in one embodiment, the refractive index of the second anti-reflection layer is n ₂ , the refractive index of air is n _A , the refractive index of the cover plate is n _G , n ₂ , n _A and _nG satisfies the following formula:

and / or

The thickness of the second anti-reflection layer is h ₂ , the wavelength of the second incident light is λ ₂ , the refractive index of the second anti-reflection layer is n ₂ , h ₂ , λ ₂ and n ₂ satisfy the following formula:
h ₂ =(1±30%)*(λ ₂ /4n ₂ )

Wherein, λ ₁ and λ ₂ are independently selected from any one of 550 nanometers, 620 nanometers to 760 nanometers, or 577 nanometers to 597 nanometers.

beneficial effects

This application uses the principle of thin film interference to reduce the reflection of light by making the reflected light at the interface between the first anti-reflective layer and the gas medium layer at least partially cancel the reflected light at the interface between the first anti-reflective layer and the flexible display module. .

Description of drawings

In order to explain the technical solutions in the present application more clearly, the drawings needed to be used in the description of the embodiments will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present application. For those skilled in the art, other drawings can also be obtained based on these drawings without exerting creative efforts.

FIG. 1 is a schematic plan view of the display device of the present application in full-screen display mode.

FIG. 2 is a schematic structural diagram of the display device of the present application in full-screen display mode.

FIG. 3 is a schematic plan view of the display device of the present application in photosensitive mode.

FIG. 4 is a schematic structural diagram of the display device of the present application in photosensitive mode.

FIG. 5 is a schematic diagram of the reflection of ambient light by a display device in the related art.

FIG. 6 is a schematic diagram of the reflection of ambient light by a display device in another related art.

FIG. 7 is a schematic structural diagram of a display device according to an embodiment of the present application.

Figure 8 is a schematic diagram of ambient light propagating in the gas medium layer, first anti-reflection film and protective layer of the present application.

FIG. 9 is a schematic diagram of a partial film thickness stack-up of a display device according to an embodiment of the present application.

FIG. 10 is a schematic diagram simulating the change in reflectivity with thickness of the film thickness stack shown in FIG. 9 .

FIG. 11 is a schematic diagram simulating the change in reflectivity with thickness of the film thickness stack shown in FIG. 6 .

Embodiments of the invention

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

In this application, unless otherwise expressly provided and limited, the first feature "above" or "below" the second feature may include the first and second features directly, or may include the first and second features not not directly connected but through additional characteristic contact between them. Furthermore, the terms "above", "above" and "above" a first feature on a second feature include the first feature being directly above and diagonally above the second feature, or simply mean that the first feature is higher in level than the second feature. “Below”, “under” and “under” the first feature is the second feature includes the first feature being directly below and diagonally below the second feature, or simply means that the first feature is less horizontally than the second feature. In addition, the terms “first” and “second” are used for descriptive purposes only and cannot be understood as indicating or implying relative importance or implicitly indicating the quantity of indicated technical features. Therefore, the features defined as “first” and “second” may explicitly or implicitly include one or more features.

This application provides a display device. The display device in the embodiment of the present application can be a mobile phone, a tablet computer, an e-reader, an electronic display screen, a notebook computer, a mobile phone, an augmented reality (AR)\virtual reality (VR) device, or a media player , wearable devices, digital cameras, car navigation systems, etc.

Please refer to FIG. 1 and FIG. 2 . The display device 100 in this embodiment is a mobile phone. The display device 100 has a flexible and slidable roll-up module stack. The display device 100 includes a middle frame 10, a scroll mechanism 20, a photosensitive module 30 and flexible display module 40. The middle frame 10 includes a bottom plate 11 and side walls 12 provided on the bottom plate 11 . The reel mechanism 20 is rotatably disposed in the middle frame 10 and is located at one end of the middle frame 10 . The photosensitive module 30 is disposed in the middle frame 10 and is located at the other end of the middle frame 10 . In other words, the reel mechanism 20 and the photosensitive module 30 are disposed at opposite ends of the middle frame 10 . The flexible display module 40 is arranged on the scroll mechanism 20. The flexible display module 40 includes a connected first part 41 and a second part 42. The first part 41 is located on the side of the scroll mechanism 20 close to the bottom plate 11 and is disposed on the bottom plate 11. The pretensioning mechanism 50 is connected to the middle frame 10 , and the second part 42 is located on the side of the reel mechanism 20 away from the bottom plate 11 . The flexible display module 40 is configured to reciprocate in the first direction X relative to the middle frame 10 to expose or block the photosensitive module 30 to enable the display device 100 to freely switch between the full-screen display mode and the photosensitive mode. Optionally, the preloading mechanism 50 can be a spring. The pre-tightening mechanism 50 enables the screen body to always maintain a moderate pre-tightening force, thereby ensuring that the screen is in a straight state during use and ensuring a better display effect of the screen. Optionally, the photosensitive module 30 includes a front camera, a face recognition sensor, etc.

In addition, the display device 100 further includes a cover 60 disposed on the side of the flexible display module 40 away from the base plate 11 . The cover 60 is used to protect the flexible display module 40 and the like. The material of the cover 60 can be plastic or glass.

As shown in Figures 1 and 2, in the full-screen display mode, the flexible display module 40 blocks the photosensitive module 30 to achieve full-screen display and increase the screen ratio of the mobile phone. Referring to Figures 3 and 4, the scroll mechanism 20 is rotated clockwise to drive the entire flexible display module 40 to curl toward the inside of the middle frame 10 of the display device 100, so that the flexible display module 40 slides downward under the cover 60. Thereby, the photosensitive module 30 hidden under the flexible display module 40 is exposed to realize the front-facing shooting function or face recognition and other functions. At this time, the display device 100 switches to the photosensitive mode to take into account the shooting or recognition functions.

It should be noted that, although not shown, the display device 100 also includes a driving mechanism installed on the middle frame 10 , and the flexible display module 40 is fixedly installed on the driving mechanism. The driving mechanism can reciprocate along the first direction X relative to the middle frame 10 to drive the flexible display module 40 to expose or block the photosensitive module 30 .

Since the flexible display module 40 needs to complete the sliding movement inside the middle frame 10 under the protection of the cover 60 , a certain gap needs to be set between the flexible display module 40 and the cover 60 , and the gap is filled with air, forming a air layer. It should be noted that the gap between the flexible display module 40 and the cover 60 is also Can be filled with other gases, for example, inert gases such as nitrogen. Therefore, the gas layer between the flexible display module 40 and the cover 60 is collectively referred to as the gas medium layer 70 . The existence of the air layer will change the propagation path of external incident light (or ambient light) and the light emitted by the flexible display module 40 . It should be noted that external incident light or ambient light refers to illumination light or natural light incident on the display device 100 from a light source other than the display device 100 in the use environment. Ambient light will be reflected twice on the surface of the cover 60 and the air layer on both sides, and the reflectivity will be increased accordingly. After entering the human eye, it is easy to form adverse optical phenomena such as glare effect and haze enhancement, affecting the overall sensory effect of the mobile phone, thereby affecting the overall sensory effect of the mobile phone. Glare is produced when the screen is closed. In addition, when the screen is on, due to the loss of the overall light intensity transmittance, the display brightness is not high, which affects the display effect.

The principle of glare generation will be explained in detail through the optical reflection formula below. As shown in Figure 5, in traditional mobile phone module design, there is no air layer between the flexible display module and the cover. The ambient light enters the flexible display module through the cover and is directly reflected to the human eye. Taking the glass cover as an example, the refractive index of the glass is n _G = 1.5, the refractive index of air n _A is 1, n _e is the reflectivity coefficient, and its value is 1. The calculation formula of the reflectivity R _λ of the glass cover is ( 1) is:

It can be calculated from this formula that after ambient light is reflected through a single layer of glass, the reflectivity of the light is approximately 4%. That is, when light passes through one side of glass from air, the reflectivity is about 4%. In fact, the reflectivity of glass measured alone is generally in the range of 4.2% to 4.5%. The reflectivity of the glass to ambient light is within the acceptable range of the human eye, and there will be no glare or heavy haze on the screen as a whole.

The propagation path of ambient light in the flexible display module 240 and the cover 260 in the structural design of a known display device is as shown in FIG. 6 . First, light I ₀ enters the cover 260 from the air A. A part of the light I ₀ is reflected for the first time at the interface between the air A and the cover 260. The reflected light I' ₀ enters the human eye; the other part of the light I ₀ I ₁ is refracted into the cover plate 260 , a part of the light ray I ₁ is reflected for the second time on the upper surface of the cover plate 260 (ie, the interface between air A and the cover plate 260 ), and the reflected light I' ₁ enters the human eye; the light ray I 1 is refracted into the cover plate 260 . The other part I ₂ of I ₁ is refracted into the cover plate 260 and is reflected for a third time at the interface between the flexible display module 240 and the gas medium layer 270 . Then it is refracted twice, and the refracted light I' ₂ enters the human eye. Since there are air layers on both sides of the cover plate 260 , reflection occurs on both the upper and lower surfaces of the cover plate 260 , so the reflectivity of the cover plate 260 for ambient light is greater than 8%. In addition, the light is reflected once at the interface between the air A and the flexible display module 240, causing the ambient light to reflect between the air A, the cover 260, and the gas medium layer 270. The reflectivity between the flexible display module 240 and the flexible display module 240 is at least 8%. In short, ambient light undergoes three reflections, and finally three different intensities of light enter the human eye, causing increased glare and haze.

To this end, this application provides a display device 100. Referring to FIG. 7 , the display device 100 includes a flexible display module 40 , a cover 60 , a gas medium layer 70 and a first anti-reflection layer 80 . The flexible display module 40 includes a light emitting surface 40a and a light incident surface 40b opposite to the light emitting surface 40a. The cover 60 is disposed on the light emitting surface 40a of the flexible display module 40 . The gas medium layer 70 is filled between the flexible display module 40 and the cover plate 60 . The first anti-reflective layer 80 is disposed on the surface of the flexible display module 40 close to the gas medium layer 70 . The refractive index of the first anti-reflective layer 80 is greater than the refractive index of the gas medium layer 70 . The function of the first anti-reflective layer 80 is to make the reflected light at the interface between the first anti-reflective layer 80 and the gas medium layer 70 at least partially consistent with the reflected light at the interface between the first anti-reflective layer 80 and the flexible display module 40 . remove.

In this application, the first anti-reflective layer 80 is formed between the flexible display module 40 and the gas medium layer 70. The refractive index of the first anti-reflective layer 80 is greater than the refractive index of the gas medium layer 70. When light enters the light from the optically sparse medium, When the medium is dense, thin film interference is utilized by causing the reflected light at the interface between the first anti-reflective layer 80 and the gas medium layer 70 to at least partially cancel the reflected light at the interface between the first anti-reflective layer 80 and the flexible display module 40 The principle of reducing light reflection.

Specifically, the flexible display module 40 includes a flexible display panel 41 and a protective layer 42 disposed on a side of the flexible display panel close to the cover 60 . It can be understood that the flexible display module 40 also includes a polarizer 43 disposed between the flexible display panel and the protective layer 42, and other film layers not shown, such as a touch layer, an optical adhesive layer, etc. Although not shown, the flexible display panel 41 includes a flexible substrate and an organic light-emitting diode device provided on the flexible substrate. Depending on the driving type, the flexible display panel 41 may be an Active Matrix Organic Light-emitting Diode (AMOLED) display panel or a Passive Matrix Organic Light-emitting Diode (PMOLED) display panel. The flexible substrate material is selected from polyimide (PI), polyethylene naphthalate (PEN), polyethylene terephthalate (PET), polyarylate (PAR), polycarbonate (PC) ), one of polyetherimide (PEI) and polyethersulfone (PES). Organic light-emitting diode devices include cathodes, anodes, organic light-emitting layers, hole injection layers, hole transport layers, electron injection layers, electron transport layers, etc. The organic light-emitting diode device can be a top-emitting OLED (Top-emitting OLED, TEOLED) device or bottom-emitting OLED (Bottom-emitting OLED, BEOLED).

The protective layer 42 may have a single-layer structure or two or more layers. In some embodiments, the protective layer 42 is made of transparent polyimide (CPI).

The cover 60 can be made of glass or plastic.

The gas medium layer 70 may be an air layer or an inert gas layer. In a specific embodiment, the thickness of the gas medium layer 70 ranges from 0.1 mm to 0.2 mm.

The first anti-reflective layer 80 may be a transparent film with a uniform thickness. Optionally, the material of the first anti-reflection layer 80 may be selected from at least one of magnesium fluoride (MgF ₂ ), silicon dioxide, aluminum oxide, titanium dioxide, silicon nitride, and the like. By forming the above materials on the surface of the cover plate 60 through chemical vapor deposition or sputtering film formation, a thin film layer with good density can be obtained. Magnesium fluoride has the advantages of low refractive index (N=1.38), low optical loss, light transmission range from 120 nanometers to 8000 nanometers, high mechanical strength of the film layer and high laser damage threshold, and it is easy to form a hard and durable coating through vacuum deposition. . Silica is colorless and transparent, has a high melting point, high hardness and good chemical stability. It has high purity and can be used to prepare high-quality SiO ₂ coatings with good evaporation state and no collapse point.

The following is a detailed description of the design principle of anti-reflection and anti-reflection in the embodiment of this patent:

Referring to FIG. 8 , the incident light is reflected at the upper and lower interfaces of the protective layer 42 , and interference also occurs between the reflected lights. If the protective layer 42 and the first anti-reflective layer 80 are treated as a thin film, the reflectance R ₁ of the thin film formed by the protective layer 42 and the first anti-reflective layer 80 can be calculated by the Fresnel formula: out:

In the formula, r ₁ is the reflection coefficient of the upper surface of the film formed by the protective layer 42 and the first anti-reflective layer 80 (ie, the upper surface of the first anti-reflective layer 80 ), and r ₂ is the reflection coefficient of the protective layer 42 and the first anti-reflective layer 80, the reflection coefficient at the upper surface of the film (ie, the lower surface of the protective layer 42), is the phase angle caused by the thickness of the first anti-reflection layer 80 . in, is the central wavelength of the ambient light, that is, the wavelength of the ambient light that is desired to be eliminated, and h ₁ is the thickness of the first anti-reflection layer 80 . r ₁ and r ₂ satisfy the following conditions:
r ₁ =(n ₀ -n ₁ )/(n ₀ +n ₁ ) (3)
r ₂ =(n ₀ -n _i )/(n ₀ +n _i ) (4)

In the formula, the refractive index of the first anti-reflection layer 80 is n ₁ , the refractive index of the gas medium layer 70 is n ₀ , and the refractive index of the protective layer is n _i .

When ambient light is vertically incident, substituting equations (3) and (4) into equation (2), we can get equation (5):

To achieve the best anti-reflection effect, the incident light reflectance R ₁ on the surface of the protective layer should be 0, and equation (6) should be satisfied:

Optionally, in order to obtain a better anti-reflection effect, the refractive index n _i of the protective layer 42 , n ₀ , n _i and n _i satisfy the following formula:

In addition, when the light passes through the upper surface 80a of the first anti-reflection layer 80, part of it is reflected and part of it is transmitted; when the transmitted light passes through the lower surface 80b, a part of it is reflected. This reflected part is different from the original reflection when it passes through the upper surface 80a. Light cancels out. This requires a phase difference of (2k+1)π between the reflected light and the transmitted light, where k is the number of ambient light reflections, k=0, 1, 2... The transmitted light travels 2h longer than the reflected light, so its optical path difference is (2n ₁ h ₁ +λ ₁ /2)-λ ₁ /2. λ is the wavelength of specific light in ambient light. That is to say, every half-wave loss is equivalent to an additional optical path of λ ₁ /2. What's in parentheses is the second reflected light. The following λ ₁ /2 is the reflected light of the first reflection. To completely cancel the reflected light when the incident light is vertically incident, equation (7) needs to be satisfied:
2n ₁ h ₁ =(k+1/2)λ ₁ (7)

Based on equation (6), the refractive index n ₁ of the first anti-reflection layer 80 can be made larger than the refractive index n ₀ of the gas medium layer 70 and smaller than the refractive index n _i of the protective layer 42 to reduce the anti-reflection effect. Preferably, when n ₁ , n ₀ and n _i satisfy equation (6), theoretically, the reflected light from the upper surface 80 a and the lower surface 80 b of the first anti-reflection layer 80 completely interferes and destructively. The reflected light on the surface 80a cancels the light on the lower surface 80b, that is, the reflected light on the upper surface of the protective layer 42 is eliminated, thereby reducing the reflectivity increase caused by the presence of the gas medium layer 70.

Optionally, the gas medium layer 70 is air, the refractive index n ₀ is 1, and the refractive index n _i of the protective layer 42 is 1.5. The refractive index n ₁ of the first anti-reflection layer 80 can be between 1.2 and 1.45, and the principle of thin film interference is used to minimize the reflected light. Preferably, the refractive index n ₁ of the first anti-reflection layer 80 is 1.38.

On the other hand, based on equation (7), the anti-reflection effect can be adjusted by designing the actual thickness of the first anti-reflection layer 80 . Preferably, when k=0, the minimum thickness h ₁ of the first anti-reflection film can be expressed as formula (8):
h ₁ =λ ₁ /4n ₁ (8)

Optionally, in order to obtain better anti-reflection effect, the thickness h ₁ of the first anti-reflection film can be expressed as:
h ₁ =(1±30%)*(λ ₁ /4n ₁ )

In some embodiments, for products such as mobile phones and tablet computers, the wavelength of light to which the human eye is most sensitive is 550 nanometers. The central wavelength λ ₁ of the ambient light that needs to be eliminated is 550 nanometers. In some embodiments, the anti-reflection effect of other specific wavelengths of light, such as yellow light and red light, is poor due to the presence of an air layer in between. The ambient light that needs to be eliminated is yellow light and red light, and the wavelength λ ₁ is selected from one of 620 nanometers to 760 nanometers or 577 nanometers to 597 nanometers.

In a specific embodiment, in order to achieve the best anti-reflection effect, according to the conditions that the average wavelength of ambient light is 650 nanometers and the refractive index n _i of the protective layer 42 is 2.0 to 2.1, the first anti-reflection layer 80 The thickness h ₁ is in the range of 75 nanometers to 80 nanometers, which can reduce ambient light reflection to a minimum.

Please refer to FIG. 7 again. For the cover 60, reflection occurs on both the upper and lower surfaces of the cover 60. In order to further reduce the reflection on the upper and lower surfaces of the cover 60, the display device 100 also includes a second anti-reflection layer 90. The second anti-reflective layer 90 is disposed on the surface of the cover 60 away from the flexible display module 40 (ie, the upper surface). The refractive index n ₂ of the second anti-reflective layer 90 is greater than the refractive index n _G of air. The function of the second anti-reflective layer 90 is to at least partially cancel the reflected light at the interface between the second anti-reflective layer 90 and the air and the reflected light at the interface between the second anti-reflective layer 90 and the cover plate 60 .

Based on the same design principle, optionally, the refractive index n _G of the cover plate 60 is greater than the refractive index n ₂ of the second anti-reflection layer 90 .

Further, the refractive index of the second anti-reflection layer 90 is n ₂ , the refractive index of air is n _A , the refractive index of the cover plate 60 is n _G , n ₂ , n _A and n _G satisfy the following formula (9):

Optionally, in order to obtain a better anti-reflection effect, the refractive index n ₂ of the second anti-reflection layer 90 can be expressed as:

Optionally, the thickness of the second anti-reflection layer 90 is h ₂ , the wavelength of the second incident light is λ ₂ , and the refractive index n ₂ h ₂ , λ ₂ and n ₂ of the second anti-reflection layer 90 satisfy the following formula ( 10)：
h ₂ =λ ₂ /4n ₂ (10)

Optionally, in order to obtain a better anti-reflection effect, the relationship between the refractive index n ₂ h ₂ , λ ₂ and n ₂ of the second anti-reflection layer 90 can be expressed as:
h ₂ =(1±30%)*λ ₂ /4n ₂

In some embodiments of the present application, the first anti-reflective film layer 80 can be designed for light of 550 nanometers, and the second anti-reflective layer 90 can be designed for yellow light or red light. That is, the thickness of the first anti-reflection film 80 satisfies h ₁ =λ ₁ /4n ₁ , λ ₁ is 550 nanometers, and the thickness of the second anti-reflection film satisfies h ₂ =λ ₂ /4n ₂ , and λ ₂ is 620 nanometers to 760 nanometers. Nano or 577 nanometers to 597 nanometers.

In other embodiments of the present application, the first anti-reflective layer 80 can be designed for yellow light or red light, and the second anti-reflective film layer 90 can be designed for 550 nanometer light. That is, the thickness h ₁ of the first anti-reflection film 80 satisfies h ₁ =λ ₁ /4n ₁ , λ ₁ is 620 nm to 760 nm or 577 nm to 597 nm, and the thickness h ₂ of the second anti-reflection film satisfies h ₂ = λ ₂ /4n ₂ , λ ₂ is 550 nanometers.

Please refer to Figures 9 and 10. The abscissa in Figure 10 is the total thickness of the module stack in Figure 9, which includes the protective layer 42, the first anti-reflective layer 80, the gas medium layer 70, the cover plate 60, The total thickness of the second anti-reflection layer 90 and the air layer A is in nanometers. Among them, the total thickness of the thin film protective layer 42, the gas medium layer 70, the cover plate 60 and the air layer A is 390 nanometers. The experiment started with 390 nanometers, and added the first anti-reflective layer 80 and the second anti-reflective film layer 90 thereto. The refractive index of each film layer is shown in Figure 9, and its description is omitted here. The ordinate is the reflectivity of the display device 100 for light with a wavelength of 550 nanometers, and the unit is percentage. During the experiment, the thickness h _A of the gas medium layer 70 was kept at 0.2 mm, and the total thickness of h ₁ and h ₂ was gradually increased simultaneously.

Please refer to Figure 11. The abscissa of Figure 11 is the total thickness of the module stack in Figure 6, which includes the total thickness of the flexible display module 240, the cover plate 260, the gas medium layer 270 and the air layer A. The unit is for nanometers. Moreover, the refractive index of each film layer is the same as that in Fig. 9, and its description is omitted here. The ordinate is the display device 100 Reflectance of light at a wavelength of 550 nanometers in percent. During the experiment, the thickness of the gas medium layer 270 was kept at 0.2 mm, and the thickness of the flexible display module 240 was gradually increased. Specifically, the thickness of the protective layer of the flexible display module 240 was increased.

By comparing the two, we can find:

For the display device 100 including the first anti-reflective layer 80 and the second anti-reflective layer 90, as the film thickness increases from 390 nanometers to about 420 nanometers, the reflectivity drops sharply from 4% to 0.4%, and stops the downward trend. When the film thickness is in the range of 420 nanometers to 700 nanometers, the reflectivity remains basically stable. When the film thickness increases to more than 700 nanometers, the reflectivity begins to rise again. When the film thickness increases to 780 nanometers, the reflectivity increases to 1.9 , but still not more than 4%. In contrast, in the display device 100 without the anti-reflection layer, the reflectance is greater than 4%.

The reason for the analysis may be: the anti-reflection effect of the anti-reflection layer is related to its thickness. When the anti-reflection layer is added, when the film thickness increases from 390 nanometers to 420 nanometers, the two groups of reflected light interfere destructively. When the film thickness increases from 420 nanometers to 420 nanometers, In the range from nanometers to 700 nanometers, the two sets of reflected lights continue to interfere and destructive. When the film thickness increases to more than 700 nanometers, the two sets of reflected lights interfere constructively and the reflectivity rises again. In addition, commercially available anti-reflective layers have a composite layer structure. The low-reflective effect of the anti-reflective layer is not only related to its own thickness, but also related to its own multi-layer structure.

Through the above experimental verification, the double-layer anti-reflective film design of the present application can reduce the external reflected light of a full-screen mobile phone containing an air interlayer to less than 1%, thereby improving the optical quality of the entire screen and preventing glare or glare on the entire screen. The phenomenon of heavy haze.

The above provides a detailed introduction to the implementation of the present application. This article uses specific examples to illustrate the principles and implementation of the present application. The above description of the implementation is only used to help understand the present application. At the same time, for those skilled in the art, there will be changes in the specific implementation and application scope based on the ideas of the present application. In summary, the content of this description should not be understood as a limitation of the present application.

Claims

A display device including:

Flexible display module, including light emitting surface;

A cover plate, arranged on the light-emitting surface of the flexible display module;

A gas dielectric layer filled between the flexible display module and the cover; and

A first anti-reflective layer is disposed on the surface of the flexible display module close to the gas medium layer, and the refractive index of the first anti-reflective layer is greater than the refractive index of the gas medium layer.
The display device of claim 1, wherein the display device further includes:

The middle frame includes a bottom plate and side walls provided on the bottom plate;

The scroll mechanism is rotatably installed in the middle frame and located at one end of the middle frame; and

A photosensitive element is arranged in the middle frame and located at the other end of the middle frame;

Wherein, the flexible display module is arranged on the scroll mechanism, and the flexible display module includes a connected first part and a second part. The first part is located on a side of the scroll mechanism close to the bottom plate and The second part is connected to the middle frame through a pretensioning mechanism provided on the bottom plate. The second part is located on the side of the scroll mechanism away from the bottom plate. The flexible display module is configured to be able to move relative to the middle frame. The frame reciprocates to expose or block the photosensitive element.
The display device of claim 1, wherein the flexible display module includes a flexible display panel and a protective layer disposed on a side of the flexible display panel close to the cover, and the refractive index of the protective layer is greater than the The refractive index of the first anti-reflective layer.
The display device of claim 3, wherein the first anti-reflection layer has a refractive index n 1 , the gas dielectric layer has a refractive index n 0 , and the protective layer has a refractive index n i , n 0 , n i and n i satisfy the following formula:
The display device according to claim 1, wherein the thickness of the first anti-reflection layer is h 1 , the wavelength of the first incident light is λ 1 , and the refractive index of the first anti-reflection layer is n 1 , h 1 , λ 1 and n 1 satisfy the following formula:
h 1 =(1±30%)*(λ 1 /4n 1 )

Among them, λ 1 is selected from any one of 550 nanometers, 620 nanometers to 760 nanometers, or 577 nanometers to 597 nanometers.
The display device according to claim 3, wherein the refractive index of the protective layer is 2.0 to 2.1, the gas medium layer is an air layer, the thickness of the air layer ranges from 0.1 mm to 0.2 mm, and the first The refractive index of an anti-reflective layer ranges from 1.2 to 1.45.
The display device according to claim 1, wherein the display device further includes a second anti-reflective layer, the second anti-reflective layer is disposed on a surface of the cover plate away from the flexible display module, the The refractive index of the second anti-reflective layer is greater than the refractive index of air.
The display device of claim 7, wherein the refractive index of the cover plate is greater than the refractive index of the second anti-reflection layer.
The display device according to claim 8, wherein the refractive index of the second anti-reflection layer is n 2 , the refractive index of air is n A , and the refractive index of the cover plate is n G , n 2 , n A And n G satisfies the following formula:
The display device according to claim 7, wherein

The thickness of the first anti-reflection layer is h 1 , the wavelength of the first incident light is λ 1 , the refractive index of the first anti-reflection layer is n 1 , h 1 , λ 1 and n 1 satisfy the following formula:
h 1 =(1±30%)*(λ 1 /4n 1 )

or

The thickness of the second anti-reflection layer is h 2 , the wavelength of the second incident light is λ 2 , the refractive index of the second anti-reflection layer is n 2 , h 2 , λ 2 and n 2 satisfy the following formula:
h 2 =(1±30%)*(λ 2 /4n 2 )

Wherein, λ 1 and λ 2 are independently selected from any one of 550 nanometers, 620 nanometers to 760 nanometers, or 577 nanometers to 597 nanometers.
The display device according to claim 7, wherein

The thickness of the first anti-reflection layer is h 1 , the wavelength of the first incident light is λ 1 , the refractive index of the first anti-reflection layer is n 1 , h 1 , λ 1 and n 1 satisfy the following formula:
h 1 =(1±30%)*(λ 1 /4n 1 )

The thickness of the second anti-reflection layer is h 2 , the wavelength of the second incident light is λ 2 , the refractive index of the second anti-reflection layer is n 2 , h 2 , λ 2 and n 2 satisfy the following formula:
h 2 =(1±30%)*(λ 2 /4n 2 )

Wherein, λ 1 and λ 2 are independently selected from any one of 550 nanometers, 620 nanometers to 760 nanometers, or 577 nanometers to 597 nanometers.
The display device of claim 3, wherein the first anti-reflection layer is made of at least one material selected from the group consisting of magnesium fluoride, silicon dioxide, aluminum trioxide, titanium dioxide, silicon nitride, and the like.
The display device of claim 2, wherein the display device has a full-screen display mode and a photosensitive mode, and in the full-screen display mode, the flexible display module blocks the photosensitive module, and the scroll mechanism rotates The flexible display module is driven to curl toward the inside of the middle frame, so that the flexible display module slides downward under the cover, thereby removing the photosensitive module hidden under the flexible display module. The group is revealed, and the display device switches to the photosensitive mode.
A display device including:

The middle frame includes a bottom plate and side walls provided on the bottom plate;

The scroll mechanism is rotatably installed in the middle frame and located at one end of the middle frame;

A photosensitive element is arranged in the middle frame and located at the other end of the middle frame;

A flexible display module is arranged on the scroll mechanism. The flexible display module includes a connected first part and a second part. The first part is located on the side of the scroll mechanism close to the bottom plate and is arranged on The pretensioning mechanism on the bottom plate is connected to the middle frame, the second part is located on a side of the scroll mechanism away from the bottom plate, and the flexible display module is configured to reciprocate relative to the middle frame. To expose or block the photosensitive element, the flexible display module includes a light emitting surface;

A cover plate, arranged on the light-emitting surface of the flexible display module;

A gas dielectric layer filled between the flexible display module and the cover; and

A first anti-reflective layer is disposed on the surface of the flexible display module close to the gas medium layer, and the refractive index of the first anti-reflective layer is greater than the refractive index of the gas medium layer.
The display device of claim 14, wherein the flexible display module includes a flexible display panel and a protective layer disposed on a side of the flexible display panel close to the cover, and the refractive index of the protective layer is greater than the The refractive index of the first anti-reflective layer.
The display device of claim 15, wherein the first anti-reflection layer has a refractive index n 1 , the gas dielectric layer has a refractive index n 0 , and the protective layer has a refractive index n i , n 0 , n i and n i satisfy the following formula:
The display device according to claim 14, wherein the thickness of the first anti-reflection layer is h 1 , the wavelength of the first incident light is λ 1 , and the refractive index of the first anti-reflection layer is n 1 , h 1 , λ 1 and n 1 satisfy the following formula:
h 1 =(1±30%)*(λ 1 /4n 1 )

Among them, λ 1 is selected from any one of 550 nanometers, 620 nanometers to 760 nanometers, or 577 nanometers to 597 nanometers.
The display device according to claim 14, wherein the display device further includes a second anti-reflective layer, the second anti-reflective layer is disposed on a surface of the cover plate away from the flexible display module, the The refractive index of the second anti-reflective layer is greater than the refractive index of air, and the refractive index of the cover plate is greater than the refractive index of the second anti-reflective layer.
The display device according to claim 18, wherein the refractive index of the second anti-reflection layer is n 2 , the refractive index of air is n A , and the refractive index of the cover plate is n G , n 2 , n A And n G satisfies the following formula:
The display device of claim 18, wherein

The thickness of the first anti-reflection layer is h 1 , the wavelength of the first incident light is λ 1 , the refractive index of the first anti-reflection layer is n 1 , h 1 , λ 1 and n 1 satisfy the following formula:
h 1 =(1±30%)*(λ 1 /4n 1 )

or

The thickness of the second anti-reflection layer is h 2 , the wavelength of the second incident light is λ 2 , the refractive index of the second anti-reflection layer is n 2 , h 2 , λ 2 and n 2 satisfy the following formula:
h 2 =(1±30%)*(λ 2 /4n 2 )

Among them, λ 1 and λ 2 are independently selected from 550 nanometers, 620 nanometers to 760 nanometers, or 577 nanometers to 597 nanometers. Any of the nanometers.