Display device and driving method thereof

Abstract

The invention discloses a display device and a driving method thereof. The display device comprises a backlight module and a display panel with a plurality of sub-pixel units, wherein the display panel comprises a liquid crystal layer; the display device further comprises a reflecting layer, and the reflecting layer is located between the liquid crystal layer and the backlight module. The reflecting layer is provided with a plurality of first open holes which are in one-to-one correspondence with the plurality of sub-pixel units; in the thickness direction of the display device, the projection of the first opening on the backlight module is located in the projection of the sub-pixel unit on the backlight module; the reflecting layer is used for reflecting light rays incident to the reflecting layer from one side of the liquid crystal layer; the first hole is used for transmitting light emitted to one side of the liquid crystal layer by the backlight module; the display device has a transmission-type display mode and a reflection-type display mode, and the backlight module is used for providing backlight in the transmission-type display mode and is closed in the reflection-type display mode. The problem that a reflective display device cannot be used when light is weak can be solved.

Description

Technical Field

[0001] This invention relates to the field of display technology, and in particular to a display device and its driving method. Background Technology

[0002] Display devices such as mobile phones, tablets, and monitors are widely used in modern society. Among them, reflective display devices can use ambient light as a backlight to achieve display, meaning they do not require an additional backlight, thus resulting in lower power consumption. Due to their low power consumption, reflective display devices are attracting increasing attention.

[0003] However, reflective display devices are limited by their operating environment. Because they require ambient light as a backlight, relatively strong ambient light is needed to achieve good display results; in low ambient light, the display quality is poor or even nonexistent. In other words, reflective display devices in related technologies cannot meet usage requirements in low-light conditions. Summary of the Invention

[0004] This invention provides a display device and its driving method to solve the problem that reflective display devices cannot be used in low light conditions.

[0005] According to one aspect of the present invention, a display device is provided, the display device comprising a backlight module and a display panel having a plurality of sub-pixel units, the display panel comprising a liquid crystal layer;

[0006] The display device further includes a reflective layer located between the liquid crystal layer and the backlight module; the reflective layer has a plurality of first openings corresponding one-to-one with the plurality of sub-pixel units; along the thickness direction of the display device, the projection of the first opening onto the backlight module is located within the projection of the sub-pixel unit onto the backlight module; the reflective layer is used to reflect light incident from one side of the liquid crystal layer onto the reflective layer; the first openings are used to transmit light emitted from the backlight module toward one side of the liquid crystal layer.

[0007] The display device has a transmissive display mode and a reflective display mode. The backlight module is used to provide backlight in the transmissive display mode and to be turned off in the reflective display mode.

[0008] Optionally, the area of ​​the first opening is 7% to 15% of the area of ​​the corresponding sub-pixel unit.

[0009] Optionally, along the thickness direction of the display device, the center of the projection of the first opening onto the backlight module coincides with the center of the projection of the sub-pixel unit onto the backlight module.

[0010] Optionally, the display device further includes a color filter layer, the color filter layer including a black matrix and a plurality of color filters, the black matrix separating the plurality of color filters;

[0011] The color gamut range of the color resist is 4% to 10%.

[0012] Optionally, the color filter layer further includes white light units, and the black matrix separates the white light units from the color blocker; and / or,

[0013] The color filter layer further includes an optical path adjustment layer, which is disposed on the side of the black matrix near the liquid crystal layer, and the refractive index of the optical path adjustment layer is greater than or equal to 1.5.

[0014] According to another aspect of the present invention, a display device is provided, the display device comprising a backlight module and a display panel having a plurality of sub-pixel units, the display panel comprising a liquid crystal layer;

[0015] The display device further includes a reflective layer located between the liquid crystal layer and the backlight module; the reflective layer has a plurality of first openings corresponding one-to-one with the plurality of sub-pixel units; along the thickness direction of the display device, the projection of the first opening onto the backlight module is located within the projection of the sub-pixel unit onto the backlight module; the reflective layer is used to reflect light incident from one side of the liquid crystal layer onto the reflective layer; the first openings are used to transmit light emitted from the backlight module toward one side of the liquid crystal layer.

[0016] The display device has a transmissive display mode and a reflective display mode. The backlight module is used to provide backlight in the transmissive display mode and to turn off in the reflective display mode.

[0017] The display device further includes an electrowetting module, which comprises a first electrode layer, a dielectric layer, an electrowetting unit layer, and a second electrode layer stacked sequentially; the electrowetting unit layer includes a barrier wall and a plurality of electrowetting units, the barrier wall being used to separate adjacent electrowetting units; the electrowetting units are filled with polar liquid and non-polar liquid;

[0018] The electrowetting module is disposed on the side of the display panel away from the backlight module; or, the electrowetting module is disposed between the display panel and the backlight module.

[0019] Optionally, when the electrowetting module is disposed on the side of the display panel away from the backlight module, the reflective layer is located inside the display panel;

[0020] When the electrowetting module is disposed between the display panel and the backlight module, the reflective layer is located in the electrowetting module and is located on the side of the electrowetting unit closer to the backlight module.

[0021] Optionally, when the electrowetting module is disposed on the side of the display panel away from the backlight module, the reflective layer is located between the liquid crystal layer and the pixel electrode of the display panel;

[0022] When the electrowetting module is disposed between the display panel and the backlight module, the reflective layer is located on the side of the first electrode layer away from the second electrode layer.

[0023] Optionally, a polarizing brightness enhancement film is further disposed between the backlight module and the display panel;

[0024] Alternatively, a functional layer may be provided between the backlight module and the display panel, the functional layer including a short-wavelength filter and a long-wavelength filter stacked together; a plurality of second openings are provided on the functional layer; along the thickness direction of the display device, the orthographic projection of the second openings on the backlight module coincides with the orthographic projection of the first openings on the backlight module.

[0025] According to another aspect of the present invention, a driving method for a display device is provided for driving the display device as described above, the driving method for the display device comprising:

[0026] In reflective display mode, the backlight module is turned off; a first preset voltage is applied between the first electrode layer and the second electrode layer to diffuse the light reflected from the reflective layer to the electrowetting module;

[0027] In transmissive display mode, the backlight module is turned on; a second preset voltage is applied between the first electrode layer and the second electrode layer according to the target viewing angle to diffuse or converge the emitted light of the backlight module.

[0028] Optionally, the driving method further includes:

[0029] In the reflective display mode, the magnitude of the first preset voltage is adjusted according to the intensity of the ambient light; wherein, the divergence angle of the light reflected from the reflective layer to the electrowetting module corresponding to the first preset voltage is positively correlated with the light intensity.

[0030] The technical solution of this invention employs a display device including a display panel and a backlight module. The display panel has multiple sub-pixel units and includes a liquid crystal layer. The display device also includes a reflective layer located between the liquid crystal layer and the backlight module. The reflective layer has multiple first openings corresponding one-to-one with the multiple sub-pixel units. Along the thickness direction of the display device, the projection of the first openings onto the backlight module is located within the projection of the sub-pixel units onto the backlight module. The reflective layer reflects light incident from the liquid crystal layer side onto the reflective layer. The first openings transmit light emitted from the backlight module towards the liquid crystal layer side. The display device has a transmissive display mode and a reflective display mode. The backlight module provides backlight in the transmissive display mode and is turned off in the reflective display mode. By setting the backlight module and the reflective layer, the display device has both transmissive and reflective display modes, allowing switching between display modes based on the intensity of ambient light. This ensures display even in low light conditions and low-power display in high light conditions. Furthermore, by setting openings on the reflective layer, normal display in the transmissive display mode is ensured.

[0031] It should be understood that the description in this section is not intended to identify key or essential features of the embodiments of the present invention, nor is it intended to limit the scope of the invention. Other features of the invention will become readily apparent from the following description. Attached Figure Description

[0032] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0033] Figure 1 This is a schematic diagram of the structure of a display device provided in an embodiment of the present invention;

[0034] Figure 2 A top view of a display panel provided in an embodiment of the present invention;

[0035] Figure 3 A schematic diagram of the display principle of a display device in reflective display mode provided by an embodiment of the present invention;

[0036] Figure 4 This is a schematic diagram of the structure of another display device provided in an embodiment of the present invention;

[0037] Figure 5 A schematic diagram of the display principle of a display device in transmissive display mode provided in an embodiment of the present invention;

[0038] Figure 6This is a schematic diagram of the structure of another display device provided in an embodiment of the present invention;

[0039] Figure 7 This is a schematic diagram of the structure of another display device provided in an embodiment of the present invention;

[0040] Figure 8 A flowchart of a driving method for a display device provided in an embodiment of the present invention. Detailed Implementation

[0041] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0042] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the invention described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0043] Figure 1 This is a schematic diagram of a display device provided in an embodiment of the present invention, with reference to... Figure 1 The display device includes a display panel 1 and a backlight module 2. The display panel 1 has multiple sub-pixel units SP. The display panel 1 includes a liquid crystal layer 14. The display device also includes a reflective layer 13, which is located between the liquid crystal layer 14 and the backlight module 2. The reflective layer 13 has multiple first openings 131 that correspond one-to-one with the multiple sub-pixel units SP. Along the thickness direction of the display device, the projection of the first openings 131 onto the backlight module 2 is located within the projection of the sub-pixel units SP onto the backlight module 2. The reflective layer 13 is used to reflect light incident from one side of the liquid crystal layer 14 onto the reflective layer 13. The first openings 131 are used to transmit light emitted from the backlight module 2 toward one side of the liquid crystal layer 14. The display device has a transmissive display mode and a reflective display mode. The backlight module 2 is used to provide backlight in the transmissive display mode and to be turned off in the reflective display mode.

[0044] Specifically, the display device in this embodiment is a transflective liquid crystal display (LCD) device, which has two display modes: reflective display mode and transmissive display mode. In transmissive display mode, the backlight module 2 provides backlight light. By controlling the deflection state of the liquid crystal molecules in the display panel, the transmittance of the liquid crystal molecules to the light emitted from the backlight module 2 is controlled, thereby controlling the grayscale of the sub-pixel unit SP. In this embodiment, each sub-pixel unit SP includes liquid crystal molecules located in the liquid crystal layer 14. In reflective display mode, the backlight module 2 is turned off. At this time, ambient light can be used as backlight light. After the ambient light is incident on the display panel 1, it passes through the liquid crystal layer 14 and is incident on the reflective layer 13. After being reflected by the reflective layer 13, it is emitted from the display panel 1. Similarly, by controlling the deflection state of the liquid crystal molecules, the transmittance of the liquid crystal molecules to the emitted light can be controlled, thereby controlling the grayscale of the sub-pixel unit SP. The display device of this embodiment, by setting a reflective layer 13 and a backlight module 2, can adopt a transmissive display mode when the ambient light is dim, thereby avoiding the problem of not being able to display; while when the ambient light is bright, it can adopt a reflective display mode, thereby reducing the power consumption of the display device.

[0045] Furthermore, in this embodiment, the reflective layer 13 is disposed between the liquid crystal layer 14 and the backlight module 2. In the reflective display mode, ambient light only needs to pass through the reflective layer 13 once before passing through the liquid crystal layer 14 and exiting the display panel 1, which can reduce light loss. It also avoids light loss caused by a large optical path between the ambient light's incidence on the display panel and its exit from the display panel. The number of sub-pixel units SP corresponds one-to-one with the number of first openings 131. The reflective layer 13 is opaque. First openings 131 are provided at the positions of the reflective layer 13 corresponding to the sub-pixel units SP, so that in the transmissive display mode, the light emitted from the backlight module 2 can enter the sub-pixel units SP, thereby ensuring that the sub-pixel units SP can be displayed.

[0046] In summary, this embodiment, by incorporating a backlight module 2 and a reflective layer 13, enables the display device to operate in both transmissive and reflective display modes, switching between modes based on ambient light intensity. This ensures display capability even in low light conditions and low-power display in high light conditions. Furthermore, by providing openings in the reflective layer 13, normal display functionality is guaranteed in transmissive display mode.

[0047] The technical solution of this embodiment employs a display device including a display panel and a backlight module. The display panel has multiple sub-pixel units and includes a liquid crystal layer. The display device also includes a reflective layer located between the liquid crystal layer and the backlight module. The reflective layer has multiple first openings corresponding one-to-one with the multiple sub-pixel units. Along the thickness direction of the display device, the projection of the first openings onto the backlight module is located within the projection of the sub-pixel units onto the backlight module. The reflective layer reflects light incident from the liquid crystal layer side onto the reflective layer. The first openings transmit light emitted from the backlight module towards the liquid crystal layer side. The display device has a transmissive display mode and a reflective display mode. The backlight module provides backlight in the transmissive display mode and is turned off in the reflective display mode. By setting the backlight module and the reflective layer, the display device has both transmissive and reflective display modes, allowing switching between display modes based on the intensity of ambient light. This ensures display even in low light conditions and low-power display in high light conditions. Furthermore, by setting openings on the reflective layer, normal display in the transmissive display mode is ensured.

[0048] Optionally, such as Figure 2 As shown, Figure 2 This is a top view of a display panel provided in an embodiment of the present invention. Multiple sub-pixel units SP in the display panel can be arranged in an array along a first direction X and a second direction Y. The first direction X can be a row direction, and the second direction Y can be a column direction. The thickness direction of the display device can be understood as the third direction Z, and will be referred to as the third direction Z in the following description.

[0049] Optionally, the reflective layer 13 may be a metal layer, and the plurality of first openings 131 on the reflective layer 13 correspond one-to-one with the plurality of sub-pixel units SP of the display panel 1. The metal layer has a planar structure, which avoids appearance problems of the display device caused by unevenness. It also makes both sides of the liquid crystal layer relatively flat, which will not affect the liquid crystal alignment and avoid the problem of inconsistent arrangement of liquid crystals within a pixel (i.e., domain problem), thus improving the display effect.

[0050] Optionally, the dimensions of different sub-pixel units SP on the plane formed by the first direction X and the second direction Y can be the same or different.

[0051] Optionally, in some embodiments, the display device may be a display device with only grayscale display function, such as a black and white grayscale image. In this case, the display device does not need to have a color filter layer, which can further reduce costs.

[0052] Alternatively, in some other embodiments, the display device may be a display device with color display function, which can achieve full-color display by providing a color filter layer.

[0053] Optionally, the display device can be such as a mobile phone, tablet, MP3 player, MP4 player, smartwatch, or smart helmet, etc., and may be equipped with a light sensor to detect the intensity of ambient light. The display device can automatically switch display modes according to the intensity of ambient light. Of course, the display mode can also be set by the user.

[0054] Optionally, refer to Figure 2 The area of ​​the first opening 131 is 7% to 15% of the area of ​​the corresponding sub-pixel unit SP.

[0055] Specifically, the area mentioned in this embodiment refers to the area on the plane formed by the first direction X and the second direction Y. If the area of ​​the first opening 131 is too large, in the reflective display mode, less light is reflected back to the liquid crystal layer 14 by the reflective layer 13, affecting the display brightness; while if the area of ​​the first opening 131 is too small, in the transmissive display mode, less light from the backlight module 2 passes through the reflective layer 13, affecting the display brightness. The setting of this embodiment can ensure that sufficient light passes through the liquid crystal layer 14 and is emitted from the display panel 1 in both the reflective and transmissive display modes, thereby ensuring that the display device has a high display brightness. For example, the area of ​​the first opening 131 is 7%, 8%, 9%, 10%, 11%, 12%, 13%, 14%, or 15% of the area of ​​the corresponding sub-pixel SP.

[0056] Optionally, continue to refer to Figure 2 Along the thickness direction of the display device, the projection center of the first opening 131 on the backlight module 2 coincides with the projection center of the sub-pixel unit SP on the backlight module 2.

[0057] Specifically, in this embodiment, in the transmissive display mode, a larger portion of the emitted light from the backlight module 2 is directly incident on the sub-pixel unit SP, thereby ensuring the display effect. In some embodiments, the shape of the first opening 131 can be the same as the shape of the corresponding sub-pixel unit SP, for example, both can be circular, both can be rectangular, or both can be other types of polygons.

[0058] Optionally, continue to refer to Figure 1 The display device also includes a color filter layer 16, which includes a black matrix 161 and multiple color resists, with the black matrix 161 separating the multiple color resists; the color gamut range of the color resists is 4% to 10%.

[0059] Specifically, the display device of this embodiment can achieve color display by providing a color filter layer 16. The color resists in the color filter layer 16 may include a red color resist R, a green color resist G, and a blue color resist B. The color resists can absorb some wavelengths of white light, allowing only specific wavelengths of light to pass through. For example, the red color resist R allows red light to pass through, so that only red light remains after white light passes through the red color resist R; the green color resist G allows green light to pass through, and the blue color resist B allows blue light to pass through. The black matrix 161 can be understood as a black-masking structure, which can prevent crosstalk between two adjacent sub-pixel units SP. In some embodiments, the area corresponding to the color resist is the same as the area corresponding to the sub-pixel unit SP; in other words, the black matrix 161 defines the area where each sub-pixel unit SP is located.

[0060] The color gamut of the color resist is, for example, the NTSC (National Television Standards Committee) color gamut. A higher NTSC indicates purer light passing through the color resist; for example, less red light mixed with other colors. Conversely, a lower NTSC indicates less pure light passing through the color resist; for example, more red light mixed with other colors. Correspondingly, a higher NTSC results in less light passing through the color resist, leading to lower overall brightness; while a lower NTSC results in more light passing through the color resist, leading to higher overall brightness. In this embodiment, the color resist has a lower color gamut, allowing more light to pass through. This results in more ambient light entering the display panel 1 in reflective display mode and being reflected by the reflective layer 13, thereby increasing the brightness in reflective display mode. For example, the color gamut of the color resist may be 4%, 5%, 6%, 7%, 8%, 9%, or 10%.

[0061] Optionally, such as Figure 1 As shown, in some embodiments, the color filter layer 16 can be disposed inside the display panel 1. Of course, in other embodiments, the color filter layer 16 can also be disposed outside the display panel 1. It is understood that the display panel 1 includes a first substrate 11 and a second substrate 17 disposed opposite each other. The first substrate 11 can be a thin-film transistor substrate, and a pixel driving circuit is disposed within the first substrate 11, with pixel electrodes 12 disposed on the first substrate 11. The second substrate 17 can be a glass substrate, and a common electrode 15 is disposed on the side of the second substrate 17 closest to the first substrate 11. When the color filter layer 16 is disposed inside the display panel 1, the color filter layer 16 can be disposed between the second substrate 17 and the common electrode 15; when the color filter layer 16 is disposed outside the display panel 1, the color filter layer 16 can be disposed on the surface of the second substrate 17 away from the first substrate 11. The pixel electrodes 12 and the common electrode 15 can be made of transparent materials such as indium tin oxide (ITO). The specific display principle of the display panel is well known to those skilled in the art and will not be described in detail here.

[0062] Optionally, continue to refer to Figure 1 The color filter layer 16 also includes a white light unit W, and a black matrix 161 is used to separate the white light unit W from the color blocker.

[0063] Specifically, the white light unit W can transmit white light, that is, it can transmit light of all colors. The white light unit W can be obtained by filling the area defined by the black matrix 161 with transparent material or by not filling it; the transparent material is, for example, OC, etc. Of course, the white light unit can also be filled with white light color resist that can diffuse white light. In reflective display mode, since the white light unit W can transmit ambient light of any color, setting the white light unit W can increase the amount of ambient light transmitted through the color filter layer 16 into the display panel 1, that is, increase the overall light transmittance of the color filter layer 16, thereby further enhancing the brightness of the display panel in reflective display mode.

[0064] Optionally, in some embodiments, the display panel may include multiple pixel units arranged in an array. If no white light unit W is provided, each pixel unit includes a red sub-pixel unit, a green sub-pixel unit, and a blue sub-pixel unit. When the white light unit W is provided, each pixel unit includes a red sub-pixel unit, a green sub-pixel unit, a blue sub-pixel unit, and a white sub-pixel unit. The color resist corresponding to the red sub-pixel unit is a red color resist R, the color resist corresponding to the green sub-pixel unit is a green color resist G, the color resist corresponding to the blue sub-pixel unit is a blue color resist B, and the white sub-pixel unit corresponds to the white light unit W.

[0065] Optionally, Figure 3 This is a schematic diagram of the display principle of a display device in reflective display mode according to an embodiment of the present invention, with reference to... Figure 1 and Figure 3 The color filter layer 16 also includes an optical path adjustment layer 162, which is disposed on the side of the black matrix 16 near the liquid crystal layer 14. The refractive index of the optical path adjustment layer 162 is greater than or equal to 1.5.

[0066] Specifically, because color resist has a low color gamut, although it can increase brightness in reflective display mode, it will result in a lower color gamut in the final displayed image. For example... Figure 3 As shown, by setting the optical path adjustment layer 162, when ambient light is incident on the reflective layer 13 and then reflected by the reflective layer 13 to the color resist, some of the reflected light will pass through the optical path adjustment layer 162 and obliquely enter the color resist. The optical path adjustment layer 162 has a high refractive index, which allows a large amount of light to be refracted into the color resist and also allows the light path to be longer. The longer the optical path, the higher the final color gamut. In other words, by setting the optical path adjustment layer 162, the problem of a low color gamut in the display image caused by the low color gamut of the color resist can be at least partially compensated.

[0067] Optionally, such as Figure 1 and Figure 3 As shown, the optical path adjustment layer 162 can be made of OC adhesive, etc.

[0068] Optionally, such as Figure 1 and Figure 3 As shown, in the third direction Z, the orthographic projection of the optical path adjustment layer 162 on the backlight module 2 coincides with the orthographic projection of the black matrix 161 on the backlight module 2.

[0069] Optionally, such as Figure 1 and Figure 3 As shown, the total thickness of the optical path adjustment layer 162 and the black matrix 161 is the same as the thickness of the color resist.

[0070] Optionally, such as Figure 1 and Figure 3 As shown, the thickness of the optical path adjustment layer 162 can be less than the thickness of the black matrix 161.

[0071] Based on the same inventive concept, the present invention also provides a display device, such as... Figure 4 As shown, Figure 4 This is a schematic diagram of another display device provided in an embodiment of the present invention. The display device of this embodiment includes the display device described in any of the above embodiments. In addition, the display device of this embodiment also includes an electrowetting module 3. The electrowetting module 3 includes a first electrode layer 32, a dielectric layer 33, an electrowetting unit layer 34, and a second electrode layer 35 stacked sequentially. The electrowetting unit layer 34 includes a barrier 341 and a plurality of electrowetting units 342. The barrier 341 is used to separate adjacent electrowetting units 342. The electrowetting units 342 are filled with a polar liquid 3421 and a non-polar liquid 3422.

[0072] Specifically, the electrowetting module 3 may further include a third substrate 31 and a fourth substrate 36 facing each other, with a first electrode layer 32 and a dielectric layer 33 sequentially disposed on the third substrate 31. The first electrode layer 32 is, for example, a transparent electrode layer, and may be made of ITO material, etc. The dielectric layer 32 is, for example, an insulating and hydrophobic material, such as silicon nitride, etc. A barrier 341 defines the area of ​​a plurality of electrowetting units 342. The barrier 341 may be made of a photopolymerizable material, such as fluorinated polyimide, etc. The second electrode layer 33 may be disposed across the entire surface, and may also be made of ITO material, etc. Each electrowetting unit 342 is filled with a polar liquid 3421 and a non-polar liquid 3422 that are in contact with each other but immiscible. The non-polar liquid 3422 may be an oily liquid, and the polar liquid 3421 may be water. The polar liquid 3421 is located above the non-polar liquid 3422, and the non-polar liquid 3422 has a light-transmitting effect and is equivalent to a microlens.

[0073] When the first electrode layer 32 and the second electrode layer 35 are not energized, the nonpolar liquid 3422 forms a concave liquid surface on the surface of the dielectric layer 32, and the contact angle of the nonpolar liquid 3422 on the surface of the dielectric layer 32 is small. When the first electrode layer 32 and the second electrode layer 35 are energized, charge accumulates at the dielectric layer 32. The formula for calculating the contact angle between the polar liquid 3421 and the surface of the dielectric layer 32 is: .

[0074] Wherein, θ is the contact angle between the polar liquid 3421 and the surface of the dielectric layer 32 after a voltage is applied to the first electrode layer 32 and the second electrode layer 35. The initial contact angle between the polar liquid 3421 and the surface of the dielectric layer 32. It is the dielectric constant of the dielectric layer. It is the vacuum permittivity. The equation represents the interfacial tension between the gas and liquid phases, d is the effective thickness of the hydrophobic dielectric layer, and V is the applied voltage. This equation shows that the change in contact angle is proportional to the square of the voltage and is related to the dielectric constant, thickness, and interfacial tension of the dielectric layer. By setting the voltage, the contact angle can be controlled, thereby controlling the emission angle of the electrowetting unit.

[0075] It should be noted that the transmittance of the electrowetting module 3 in the visible light band is between 85% and 95%, and the transmittance can be further improved through the selection of materials and the design of the structure.

[0076] For example, in reflective display mode, ambient light enters the display panel and is reflected by the reflective layer 13 before exiting the display panel 1. At this time, most of the emitted light has a small angle with the third direction Z, meaning the viewing angle of the display device is small. The interface between the non-polar liquid and the polar liquid in the electrowetting unit 342 is configured as a convex lens relative to the reflected light, thereby causing the reflected light to diverge and increasing the viewing angle in reflective display mode.

[0077] In some embodiments, the electrowetting module fabrication process may include:

[0078] 1. Preparing the substrate. This includes selecting clean glass or other suitable substrate material and cleaning it to remove surface impurities, oil, etc. For example, it can be ultrasonically cleaned with organic solvents such as acetone and ethanol, then rinsed with deionized water, and finally dried using a drying device.

[0079] II. Electrode Layer Fabrication. This specifically includes: depositing conductive materials, such as using physical vapor deposition methods like electron beam evaporation or magnetron sputtering, to deposit a layer of transparent conductive material (e.g., indium tin oxide, ITO) on the substrate surface as the electrode material. For example, magnetron sputtering can be used in a vacuum environment to sputter target atoms or molecules onto the substrate surface by high-speed ion bombardment of the conductive material, forming a uniform conductive film. Then, photolithography is performed, i.e., photoresist is spin-coated onto the deposited conductive material layer, and the electrode pattern is transferred to the photoresist through mask exposure. The exposed or unexposed portions of the photoresist are then removed using a developer (depending on whether the photoresist is positive or negative). Finally, an etching process (e.g., wet etching using a suitable etchant) removes the conductive material not protected by the photoresist, forming the desired electrode pattern.

[0080] III. Preparation of the Insulating Layer. This specifically includes: coating the electrode layer with an insulating material, such as polyimide or silica, using methods like spin coating or spray coating. For example, when spin coating a polyimide solution, the spin coating speed and time are controlled to obtain a uniform wet insulating film. Then, a curing process is performed: the coated insulating layer is heated and cured to form a stable insulating layer, ensuring that the electrode does not directly contact the subsequent liquid and preventing short circuits. For example, the polyimide insulating layer may require baking and curing at a high temperature.

[0081] IV. Coating a hydrophobic layer, specifically including solution preparation: dissolving hydrophobic materials such as perfluoropolymers in a suitable organic solvent to prepare a hydrophobic coating solution. Coating and molding: applying the hydrophobic coating solution to the surface of the insulating layer using methods such as spin coating or dip coating, and then evaporating the organic solvent through heat treatment to form a uniform hydrophobic layer to enhance the electrowetting effect.

[0082] 5. Constructing the pixel structure includes coating photoresist and exposure / development. Coating photoresist involves spin-coating photoresist onto the surface of the hydrophobic layer. Exposure / development involves exposing the photoresist to a photomask and then developing it with a developer to form pixel walls or other pixel-defining structures, dividing the area into individual pixel regions.

[0083] VI. Filling with Liquid. This includes filling with non-polar liquids: filling the pixel area with a non-polar liquid, such as an oil. It also includes filling with polar liquids: carefully coating a non-polar liquid (such as an aqueous solution) onto the non-polar liquid to form the liquid system required for electrowetting. During the filling process, care must be taken to avoid the formation of air bubbles.

[0084] 7. Encapsulation. First, prepare the cover plate, specifically by selecting a cover plate material that matches the substrate, and then cleaning it. Next, fabricate the sealing frame, which involves applying a sealant (such as epoxy resin) to the edges of the substrate or cover plate. Finally, perform encapsulation bonding, which involves aligning and bonding the cover plate to the substrate, and using methods such as heating and pressurizing to cure the sealant, forming a sealed electrowetting device to prevent liquid leakage.

[0085] For example, such as Figure 5 As shown, Figure 5 This is a schematic diagram illustrating the display principle of a display device in transmissive display mode according to an embodiment of the present invention. In transmissive display mode, the viewing angle of the display device can be controlled by controlling the state of the electrowetting unit. For example, the interface between the non-polar liquid and the polar liquid in the electrowetting unit 342 can be configured as a convex lens relative to the transmitted light, thereby causing the transmitted light to diverge and increasing the viewing angle in transmissive display mode; alternatively, the interface between the non-polar liquid and the polar liquid in the electrowetting unit 342 can be configured as a concave lens relative to the transmitted light, thereby causing the transmitted light to converge and decreasing the viewing angle in transmissive display mode.

[0086] Optionally, in some embodiments, the plurality of electrowetting units 342 correspond one-to-one with the plurality of sub-pixel units SP. That is, the orthographic projection of the sub-pixel unit SP on the backlight module 2 at least partially overlaps with the orthographic projection of the corresponding electrowetting unit 342 on the backlight module. Preferably, the orthographic projection of the sub-pixel unit SP on the backlight module 2 may be located within the orthographic projection of the corresponding electrowetting unit 342 on the backlight module.

[0087] Optionally, in some embodiments, the first electrode layer 32 may include multiple electrodes, each corresponding to an electrowetting unit. Different electrodes can be controlled independently, thereby enabling individual control of the viewing angle of different areas of the display device. Of course, the first electrode layer 32 can also be a single, continuous electrode layer, in which case the viewing angle of the entire display device can be controlled uniformly.

[0088] Optionally, such as Figures 1 to 5As shown, in some embodiments, the electrowetting module 3 is disposed on the side of the display panel 1 away from the backlight module 2. That is, the electrowetting module 3 is disposed on the light-emitting surface side of the display device. When the electrowetting module 3 is disposed on the side of the display panel 1 away from the backlight module 2, the reflective layer 13 is located inside the display panel 1. That is, the reflective layer 13 can be located between the pixel electrode 12 and the first substrate 11; or it can be located between the pixel electrode 12 and the liquid crystal layer 14. It is understood that when the reflective layer 13 is a metal layer, an insulating layer is disposed between the reflective layer 13 and the pixel electrode 12. Preferably, the reflective layer 13 is located between the liquid crystal layer 14 and the pixel electrode 12. In this case, the reflective layer 13 will not affect the connection between the pixel electrode 12 and the first substrate 11, which helps to reduce the manufacturing difficulty of the display device.

[0089] In some other implementations, such as Figure 6 As shown, Figure 6 This is a schematic diagram of another display device provided in an embodiment of the present invention. In this embodiment, the electrowetting module 3 is disposed between the display panel 1 and the backlight module 2. The light emitted from the backlight module 2 first passes through the electrowetting module 3 for viewing angle control before entering the display panel 1. Finally, the light emitted from the display panel 1 is the light after viewing angle control.

[0090] Furthermore, when the electrowetting module 3 is disposed between the display panel 1 and the backlight module 2, the reflective layer 13 is located on the side of the electrowetting unit 342 closer to the backlight module 2. The reflective layer 13 can be disposed, for example, between the dielectric layer 33 and the first electrode layer 32, or between the first electrode layer 32 and the first substrate 31. Preferably, the reflective layer 13 is located on the side of the first electrode layer 32 away from the second electrode layer 35; that is, the reflective layer 13 is disposed between the first electrode layer 33 and the first substrate 31.

[0091] Optionally, refer to Figures 1 to 6 A polarizing brightening film 4 is also provided between the backlight module 2 and the display panel 1.

[0092] Specifically, the polarizing brightness enhancement film 4 is an advanced polarization conversion film (APCF) with polarization characteristics. The polarizing brightness enhancement film 4 can improve the reflectivity in reflective display mode and the transmittance in transmissive display mode.

[0093] In some other implementations, such as Figure 7 As shown, Figure 7This is a schematic diagram of another display device provided in an embodiment of the present invention. In this embodiment, a functional layer is further provided between the backlight module 2 and the display panel 1. The functional layer includes a short-wavelength filter 41 and a long-wavelength filter 42 stacked together. A plurality of second openings 43 are provided on the functional layer; along the thickness direction of the display device, the orthographic projection of the second openings 43 on the backlight module 2 coincides with the orthographic projection of the first opening 131 on the backlight module 2.

[0094] Specifically, both the short-pass filter (SPF) and the long-pass filter (LPF) are Bragg reflectors. The short-pass filter 41 transmits light with wavelengths below a first wavelength and reflects light with wavelengths at or above the first wavelength; the long-pass filter 42 transmits light with wavelengths above a second wavelength and reflects light with wavelengths below the second wavelength. By configuring the second wavelength to be shorter than the first wavelength, light of a specific wavelength can pass through the functional layer, thus acting similarly to a brightness enhancement film and improving transmittance. Furthermore, by providing a second opening on the functional layer, it can be ensured that the light emitted from the backlight module 2 can at least partially enter the display panel 1, allowing the display panel 1 to display normally in transmissive display mode.

[0095] It should be noted that when the display device includes a functional layer comprising a short-wavelength filter and a long-wavelength filter, a lower polarizer can also be placed between the functional layer and the backlight module 2. Of course, as... Figures 1 to 6 As shown, the display device also includes an upper polarizer 5, which is disposed on the side of the display panel 1 away from the backlight module 2, and is used for polarization detection.

[0096] Based on the same inventive concept, the present invention also provides a driving method for a display device, used to drive the corresponding device of the present invention. Figures 4 to 7 The display device provided in any embodiment. For example... Figure 8 As shown, Figure 8 A flowchart of a driving method for a display device provided in an embodiment of the present invention is shown. The driving method for the display device includes:

[0097] Step S101: In reflective display mode, turn off the backlight module; apply a first preset voltage between the first electrode layer and the second electrode layer to diffuse the light reflected from the reflective layer to the electrowetting module;

[0098] Specifically, when the ambient light is strong, the display device can operate in a reflective display mode, in which case the backlight module can be turned off to reduce the power consumption of the display device. Furthermore, in the reflective display mode, by applying a voltage to at least one of the first electrode layer 32 and the second electrode layer 35, the voltage between them is set to a first preset voltage. The electrowetting unit 342 diffuses the reflected light under the first preset voltage. Since the light path is reversible, ambient light within a large viewing angle range can pass through the electrowetting module 3 and be incident on the reflective layer 12. Moreover, the light incident on the reflective layer 12 includes light from angles other than the normal incidence angle, causing the reflective layer 12 to diffusely reflect ambient light. This results in a relatively large viewing angle in the reflective display mode, ensuring a good display effect. In other words, in the reflective display mode, controlling the electrowetting module 3 to diffuse the reflected light ensures a large viewing angle and a better display effect in the reflective display mode. It is understandable that in the initial state, that is, when no voltage is applied between the first electrode layer 32 and the second electrode layer 35, the electrowetting module 3 is in a state of diverging reflected light; according to the contact angle calculation formula mentioned above, the voltage range required for the electrowetting module 3 in this state can be calculated, that is, the range of the first preset voltage.

[0099] Step S102: In the transmissive display mode, turn on the backlight module; apply a second preset voltage between the first electrode layer and the second electrode layer according to the target viewing angle to diffuse or converge the emitted light of the backlight module.

[0100] Specifically, when the ambient light is weak, the display device can be controlled to operate in transmissive display mode, at which time the backlight module is turned on to ensure brightness. Furthermore, since the reflective layer 12 does not need to diffusely reflect ambient light, the electrowetting module 3 does not need to operate solely in a state of diverging reflected light. Therefore, the electrowetting module 3 can operate in a state of controlling the viewing angle. If a larger target viewing angle is required, the electrowetting module 3 is controlled to diverge the emitted light from the backlight module, such as controlling the contact angle so that the non-polar liquid acts as a convex lens. If a smaller target viewing angle is required, the electrowetting module 3 is controlled to converge the emitted light from the backlight module, such as controlling the contact angle so that the non-polar liquid acts as a concave lens. The specific value of the second preset voltage can be calculated according to the formula for the contact angle; this embodiment does not impose specific limitations on this.

[0101] The display mode of the display module can be controlled according to the ambient light intensity. For the specific control principle and display principle, please refer to the description of the display device section of this invention, which will not be repeated here.

[0102] The driving method of the display device in this embodiment can drive the display device to display normally when the ambient light is weak, and the viewing angle of the display device can be controlled by the electrowetting module; when the ambient light is strong, the display device can be driven to display with low power consumption, and by controlling the electrowetting module to be in a state of diverging reflected light, the display device can be controlled to have a larger viewing angle at this time to ensure the display effect.

[0103] It is understood that the target perspective can be set by the user as needed, and this embodiment does not impose specific limitations on it. In addition, steps S101 and S102 can be executed according to the user's configuration, and there is no specific order to them.

[0104] Optionally, in some embodiments, the first electrode layer and / or second electrode layer corresponding to different electrowetting units are independent. In this case, different areas of the display device can be controlled in zones, that is, the electrowetting units in different areas can be controlled to be in different states, so that the viewing angle of different areas can be independently controlled according to needs.

[0105] Optionally, in some embodiments, the driving method further includes: in reflective display mode, adjusting the magnitude of a first preset voltage according to the light intensity of ambient light; wherein the divergence angle of the light reflected from the reflective layer 12 to the electrowetting module 3 corresponding to the first preset voltage is positively correlated with the light intensity.

[0106] Specifically, in this embodiment, although the electrowetting module is in a state of diverging reflected light in reflective display mode, the divergence angle of the reflected light can be adjusted according to the intensity of the ambient light to improve contrast. More specifically, if the ambient light is weak and the divergence angle is too large, due to the diffuse reflection of the reflective layer 12, some light will be absorbed inside the display device, resulting in weaker and more diffused light reflected from the reflective layer 12 to the outside of the display device, leading to lower contrast and poorer display effect. Therefore, by configuring a second preset voltage, the corresponding divergence angle is made smaller, ensuring sufficient light can be emitted to the outside of the display device to improve contrast and guarantee display effect. Conversely, when the light intensity is strong, a large amount of light will be reflected to the outside of the display device, resulting in a higher contrast. In this case, by configuring a second preset voltage, the corresponding divergence angle is made larger to maximize the viewing angle of the display device.

[0107] It should be understood that the various forms of processes shown above can be used, with steps reordered, added, or deleted. For example, the steps described in this invention can be executed in parallel, sequentially, or in different orders, as long as the desired result of the technical solution of this invention can be achieved, and this is not limited herein.

[0108] The specific embodiments described above do not constitute a limitation on the scope of protection of this invention. Those skilled in the art should understand that various modifications, combinations, sub-combinations, and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this invention should be included within the scope of protection of this invention.

Claims

1. A display device, characterized in that, The display device includes a backlight module and a display panel having multiple sub-pixel units, the display panel including a liquid crystal layer; The display device further includes a reflective layer located between the liquid crystal layer and the backlight module; the reflective layer has a plurality of first openings corresponding one-to-one with the plurality of sub-pixel units; along the thickness direction of the display device, the projection of the first opening onto the backlight module is located within the projection of the sub-pixel unit onto the backlight module; the reflective layer is used to reflect light incident from one side of the liquid crystal layer onto the reflective layer; the first openings are used to transmit light emitted from the backlight module toward one side of the liquid crystal layer. The display device has a transmissive display mode and a reflective display mode. The backlight module is used to provide backlight in the transmissive display mode and to be turned off in the reflective display mode.

2. The display device according to claim 1, characterized in that, Along the thickness direction of the display device, the center of the projection of the first opening onto the backlight module coincides with the center of the projection of the sub-pixel unit onto the backlight module.

3. The display device according to claim 1, characterized in that, The display device further includes a color filter layer, which includes a black matrix and a plurality of color filters, wherein the black matrix separates the plurality of color filters. The color gamut range of the color resist is 4% to 10%.

4. The display device according to claim 3, characterized in that, The color filter layer further includes white light units, and the black matrix separates the white light units from the color blocker; and / or, The color filter layer further includes an optical path adjustment layer, which is disposed on the side of the black matrix near the liquid crystal layer, and the refractive index of the optical path adjustment layer is greater than or equal to 1.

5.

5. A display device, characterized in that, The display device includes a backlight module and a display panel having multiple sub-pixel units, the display panel including a liquid crystal layer; The display device further includes a reflective layer located between the liquid crystal layer and the backlight module; the reflective layer has a plurality of first openings corresponding one-to-one with the plurality of sub-pixel units; along the thickness direction of the display device, the projection of the first opening onto the backlight module is located within the projection of the sub-pixel unit onto the backlight module; the reflective layer is used to reflect light incident from one side of the liquid crystal layer onto the reflective layer; the first openings are used to transmit light emitted from the backlight module toward one side of the liquid crystal layer. The display device has a transmissive display mode and a reflective display mode. The backlight module is used to provide backlight in the transmissive display mode and to turn off in the reflective display mode. The display device further includes an electrowetting module, which comprises a first electrode layer, a dielectric layer, an electrowetting unit layer, and a second electrode layer stacked sequentially; the electrowetting unit layer includes a barrier wall and a plurality of electrowetting units, the barrier wall being used to separate adjacent electrowetting units; the electrowetting units are filled with polar liquid and non-polar liquid; The electrowetting module is disposed on the side of the display panel away from the backlight module; or, the electrowetting module is disposed between the display panel and the backlight module.

6. The display device according to claim 5, characterized in that, When the electrowetting module is disposed on the side of the display panel away from the backlight module, the reflective layer is located inside the display panel; When the electrowetting module is disposed between the display panel and the backlight module, the reflective layer is located in the electrowetting module and is located on the side of the electrowetting unit closer to the backlight module.

7. The display device according to claim 6, characterized in that, When the electrowetting module is disposed on the side of the display panel away from the backlight module, the reflective layer is located between the liquid crystal layer and the pixel electrode of the display panel; When the electrowetting module is disposed between the display panel and the backlight module, the reflective layer is located on the side of the first electrode layer away from the second electrode layer.

8. The display device according to claim 5, characterized in that, A polarizing brightness enhancement film is also provided between the backlight module and the display panel; Alternatively, a functional layer may be provided between the backlight module and the display panel, the functional layer including a short-wavelength filter and a long-wavelength filter stacked together; a plurality of second openings are provided on the functional layer; along the thickness direction of the display device, the orthographic projection of the second openings on the backlight module coincides with the orthographic projection of the first openings on the backlight module.

9. A driving method for a display device, used to drive the display device according to any one of claims 5-8, characterized in that, The driving method for the display device includes: In reflective display mode, the backlight module is turned off; a first preset voltage is applied between the first electrode layer and the second electrode layer to diffuse the light reflected from the reflective layer to the electrowetting module; In transmissive display mode, the backlight module is turned on; a second preset voltage is applied between the first electrode layer and the second electrode layer according to the target viewing angle to diffuse or converge the emitted light of the backlight module.

10. The driving method for the display device according to claim 9, characterized in that, The driving method further includes: In the reflective display mode, the magnitude of the first preset voltage is adjusted according to the intensity of the ambient light; wherein, the divergence angle of the light reflected from the reflective layer to the electrowetting module corresponding to the first preset voltage is positively correlated with the light intensity.

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