Reflective display device, display panel and display screen

Abstract

A reflective display device, a display panel and a display screen. In the reflective display device, an antenna array (302) composed of a dielectric material array (3021) and an electrochromic material film (3022) is arranged on one side of a substrate (301), and a control circuit (303) is connected to the electrochromic material film (3022) through a conductive material, and an electric signal is given to the electrochromic material to control the change of the imaginary part of the refractive index of the electrochromic material film (3022), thereby realizing the change of the display brightness of a specific color. Therefore, different colors and brightness can be displayed by antenna arrays (302) of different geometric sizes, and various colors can be displayed according to different combinations of colors and brightness.

Description

Technical Field

[0001] The present application relates to the field of display technology, and in particular to a reflective display device, a display panel and a display screen. Background Art

[0002] Most display devices used in electronic devices use self-luminous transmissive display technology, such as liquid crystal display, organic electroluminescent display, etc. Since the brightness of self-luminous transmissive display technology is much different from that of ambient light, it is easy to irritate the human eye, causing dry eyes and fatigue. In order to solve the problems of self-luminous transmissive display technology, reflective display technology that uses ambient light and has an eye protection effect has been developed.

[0003] The existing reflective display technologies mainly include emissive liquid crystal display, electrophoretic display, electrowetting display and micro-electro-mechanical system (MEMS) display. Among them, reflective liquid crystal display technology has the disadvantages of low reflectivity, large thickness and high energy consumption; electrophoretic display technology has the disadvantages of low resolution, complex processing, low reflectivity and low refresh rate; electrowetting display has the disadvantages of complex design process, high driving voltage, low resolution and complex processing; and micro-electro-mechanical system display technology has the disadvantages of low processing yield, high cost and poor stability. Summary of the invention

[0004] The embodiments of the present application provide a reflective display device, a display panel and a display screen, which are used to solve the problems of low resolution, low reflectivity, high energy consumption and complex processing of existing reflective display devices, so as to improve the resolution and reflectivity of the reflective display device and reduce product power consumption and cost.

[0005] In order to achieve the above objectives, this application adopts the following technical solutions:

[0006] In a first aspect, the present application provides a reflective display device. The reflective display device comprises: a substrate, an antenna array and a control circuit. Among them, the antenna array is arranged on one side of the substrate. The antenna array comprises a dielectric material array arranged in a periodic manner and an electrochromic material film covering the surface of the dielectric material array; the dielectric material array is used to reflect visible light to form a reflection peak. The dielectric material refers to a substance that can be highly electrically polarized, and the dielectric material array refers to a dielectric material that is made into a fixed shape and arranged according to certain rules, such as a square array arrangement or a hexagonal array arrangement. The electrochromic material refers to the optical properties of the material, such as reflectivity, transmittance and absorptivity, which undergo a stable and reversible color change under the action of an external electric field, and is manifested in a reversible change in color and transparency in appearance. For example, in the reflective display device in the embodiment of the present application, the electrochromic material film can change the imaginary part of the refractive index of the electrochromic material film when a voltage is applied, so that the light absorption rate of the electrochromic material changes, that is, the height of the reflection peak of the formed reflection spectrum changes, which is ultimately reflected in the change of color and brightness. The control circuit is connected to the electrochromic material film through the conductive material, and is used to adjust the imaginary part of the refractive index of the electrochromic material film to adjust the reflection peak formed by the dielectric material array to the visible light.

[0007] Based on the reflective display device provided in the first aspect, an antenna array composed of a dielectric material array and an electrochromic material film is arranged on one side of the substrate, and a control circuit is connected to the electrochromic material film through a conductive material, and an electric signal is given to the electrochromic material to control the change of the imaginary part of the refractive index of the electrochromic material film by the electric signal, thereby realizing the change of the display brightness of a specific color. Thus, different colors and brightness can be displayed by antenna arrays of different geometric sizes, and various colors can be displayed according to different combinations of colors and brightness. In the reflective display device provided in the first aspect, the nanometer-scale antenna array can support the optical resonance mode, realize the reflection peak with high reflectivity and narrow bandwidth, thereby improving the resolution and reflectivity of the display device. Among them, the antenna array is made of dielectric material and can be produced by a semiconductor manufacturing method, which can reduce the production cost. The imaginary part of the refractive index of the electrochromic material can be continuously controlled by an electric signal, thereby realizing the continuous change of the brightness of a specific color, and realizing the display of different colors and brightness by using the principle of additive color method. In addition, electrochromic materials also have a bistable property. The state of the electrochromic material when the optical loss changes can be maintained continuously without the need to continuously apply an electrical signal. Therefore, the electrochromic material does not need to consume energy continuously when achieving brightness adjustment, thereby reducing the energy consumption of the entire display device. The thickness of the electrochromic material film is nanometer-level. When performing optical modulation, the thinner the thickness of the electrochromic material film, the better the adjustment effect of the imaginary part of the refractive index of the electrochromic material film, and the faster the response speed. In addition, due to the resonance effect, a strong local electromagnetic field will be generated around the dielectric material array, which can further improve the adjustment effect and response speed of the imaginary part of the refractive index of the electrochromic material.

[0008] In a possible implementation, a first conductive layer is provided between the dielectric material array and the electrochromic material film; a second conductive layer is provided on the side of the electrochromic material film away from the dielectric material array, and both the first conductive layer and the second conductive layer are connected to the control circuit. In this possible implementation, in order to enable the electrochromic material film to adjust the imaginary part of the refractive index of the electrochromic material under the control of the electrical signal and realize the adjustment of the brightness of a specific color, it is necessary to respectively provide conductive layers on the upper and lower sides of the electrochromic material film for the transmission of the electrical signal, thereby further enabling the antenna array to realize the display of various colors.

[0009] Further, the refractive index of the material of the dielectric material array is greater than the refractive index of the material of the substrate. In this further solution, the large refractive index contrast enables the antenna array to generate a sufficiently strong localized mode of the light field to support a reflection peak with high reflectivity and narrow bandwidth.

[0010] Optionally, the real part of the refractive index of the material of the dielectric material array is greater than 2.

[0011] Optionally, the real part of the refractive index of the material of the substrate is less than 2.

[0012] Optionally, one side of the substrate on which the antenna array is disposed is made of a transparent material, which is beneficial for reflecting ambient light.

[0013] Optionally, the material of the dielectric material array may include one or more of the following: silicon, silicon nitride, gallium nitride and titanium dioxide.

[0014] In a second aspect, the present application provides a display panel. The display panel includes: a plurality of pixel units, the plurality of pixel units are arranged periodically, and each pixel unit includes a plurality of reflective display devices; the reflective display device is any possible reflective display device as described in the first aspect above. In this way, the plurality of reflective display devices can display different colors respectively, and together form a pixel unit as a color pixel unit. The color pixel units can be arranged periodically to form a color display panel. The brightness of each pixel unit can be adjusted by independent control of the control circuits in the different reflective display devices in each pixel unit, thereby realizing the display of a color image.

[0015] In a possible implementation, each pixel unit includes at least three reflective display devices; wherein, in different reflective display devices, the antenna widths in the antenna arrays are different, and the array periods of the antenna arrays are different. Thus, different antenna widths and different array periods of the antenna arrays can display different colors, thereby realizing the display of color images.

[0016] In a third aspect, the present application provides a display screen, which includes: a display driver, and any possible display panel of the second aspect, wherein the display driver is connected to the display panel and is used to control the display panel to display images.

[0017] In a fourth aspect, the present application provides an electronic device, which includes a driving circuit and a display screen as provided in the third aspect above.

[0018] In a fifth aspect, the present application provides an image display control method. The image display control method is applied to a display screen, which includes a display driver and a display panel. The display driver is connected to the display panel and is used to control the display panel to perform image display. The display panel includes a plurality of pixel units, and the plurality of pixel units are periodically arranged, and each pixel unit includes a plurality of reflective display devices. The reflective display device includes: a substrate; an antenna array, which is arranged on one side of the substrate; the antenna array includes a periodically arranged dielectric material array and an electrochromic material film covering the surface of the dielectric material array; the dielectric material array is used to reflect visible light to form a reflection peak; a control circuit, which is connected to the electrochromic material film through a conductive material, and is used to adjust the imaginary part of the refractive index of the electrochromic material film to adjust the reflection peak formed by the dielectric material array to visible light.

[0019] The image display control method includes: a display driver receives an image display signal. The display driver sends a display control signal to a control circuit of each reflective display device in each pixel unit according to the image display signal. The control circuit adjusts the imaginary part of the refractive index of the electrochromic material film in each reflective display device according to the display control signal to adjust the brightness of each reflective display device. The display panel displays an image corresponding to the image display signal.

[0020] In one possible implementation, the control circuit adjusts the imaginary part of the refractive index of the electrochromic material film in each reflective display device according to a display control signal, including: the control circuit outputs a control voltage, the control voltage is determined according to the display control signal, and the control voltage is used to adjust the imaginary part of the refractive index of the electrochromic material film in each display device.

[0021] It can be understood that the display panel, display screen, electronic device, image display control method, etc. provided above can all be implemented by the reflective display device provided above or be associated with the reflective display device provided above. Therefore, the beneficial effects that can be achieved can refer to the beneficial effects of the reflective display device provided above and will not be repeated here. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 A schematic diagram of the structure of an electronic device provided in an embodiment of the present application;

[0023] Figure 2 A schematic diagram of the display principle structure of a display panel provided in an embodiment of the present application;

[0024] Figure 3 A top view of a reflective display device provided in an embodiment of the present application;

[0025] Figure 4A schematic structural diagram of a reflective display device provided in an embodiment of the present application;

[0026] Figure 5 A schematic structural diagram of another reflective display device provided in an embodiment of the present application;

[0027] Figure 6 A schematic structural diagram of a pixel unit composed of three reflective display devices provided in an embodiment of the present application;

[0028] Figure 7 Reflection spectrum waveform of the reflective display device provided in the embodiment of the present application Figure 1 ;

[0029] Figure 8 Reflection spectrum waveform of the reflective display device provided in the embodiment of the present application Figure 2 ;

[0030] Fig. 9 A schematic structural diagram of a specific example of a reflective display device provided in an embodiment of the present application;

[0031] Fig.10 for Fig. 9 In the specific example shown, the reflection spectrum waveform diagram of the electrochromic material when the refractive index is zero;

[0032] Fig.11 for Fig. 9 A schematic diagram showing the position of the structural colors produced by the specific example shown in the CIE 1931 chromaticity diagram;

[0033] Fig.12 for Fig. 9 In the specific example shown, a reflection spectrum waveform diagram when the refractive index of the electrochromic material increases;

[0034] Fig.13 A flowchart of an image display control method provided in an embodiment of the present application.

[0035] Reference numerals:

[0036] 01-display screen; 201-pixel unit; 2011-first single pixel unit; 2012-second single pixel unit; 2013-third single pixel unit; 301-substrate; 302-antenna array; 3021-dielectric material array; 3022-electrochromic material film; 303-control circuit; 304-first conductive layer; 305-second conductive layer; 306-electrolyte layer. DETAILED DESCRIPTION

[0037] The following is an explanation of the terms used in the embodiments of the present application:

[0038] 1) Dielectric material

[0039] The dielectric material involved in this application refers to a dielectric. A dielectric is an insulator that can be electrically polarized, and generally refers to a highly electrically polarizable substance, such as silicon, silicon nitride, gallium nitride, titanium dioxide, and the like.

[0040] 2) Electrochromic materials

[0041] The electrochromic material referred to in this application refers to the phenomenon that the optical properties of the material, such as reflectivity, transmittance and absorptivity, undergo stable and reversible color changes under the action of an external electric field, which is manifested in appearance as reversible changes in color and transparency.

[0042] 3) Structural color

[0043] The structural color involved in this application refers to the color produced by the scattering, interference or diffraction of light when light is incident on an object with a spatial period similar to the wavelength.

[0044] 4) Additive color method

[0045] The additive color method involved in this application refers to a method of mixing specific colors in different proportions to form a new color; the specific color may refer to the three primary colors of red, green, and blue, or may refer to other colors.

[0046] The technical solutions in the embodiments of the present application will be described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all of the embodiments.

[0047] In the following, the terms "first", "second", etc. are used for descriptive purposes only and are not to be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first", "second", etc. may explicitly or implicitly include one or more of the features.

[0048] In addition, in the present application, directional terms such as "up", "down", "left", "right", "horizontal" and "vertical" are defined relative to the orientation of the components in the drawings. It should be understood that these directional terms are relative concepts. They are used for relative description and clarification, and they may change accordingly according to the changes in the orientation of the components in the drawings.

[0049] An embodiment of the present application provides an electronic device (such as Figure 1The electronic device may be a mobile phone, a tablet computer, a smart wearable device, a product tag, a personal digital assistant (PDA), a car computer, an electronic paper reader, etc. The embodiments of the present application do not impose any special restrictions on the specific form of the above electronic devices.

[0050] The electronic device has a driving circuit ( Figure 1 01, wherein the driving circuit is used to control the electronic device to perform corresponding functions; the display screen 01 includes a display driver and a display screen 02. Figure 2 The display panel shown in FIG. Wherein, the display driver is connected as shown in FIG. Figure 2 The display panel shown can be used to control the display panel to display images.

[0051] The embodiment of the present application also provides a display panel (such as Figure 2 The display panel includes a plurality of Figure 2 The pixel unit 201 shown in (c) in FIG. 1 is a color pixel unit, and multiple pixel units 201 are arranged periodically. The periodic arrangement may be repeated in the horizontal and vertical directions of the display panel to fill the entire display panel, such as Figure 2 As shown in (b) in FIG. 1 , the display panel can be controlled to display the following Figure 2 The image shown in (a).

[0052] refer to Figure 2 , each pixel unit 201 has a combination of multiple colors, such as a combination of red, green, and blue, that is, each pixel unit 201 has multiple single pixel units. Using the principle of color additive, various colors can be displayed by combining multiple colors with different brightness. For example, each pixel unit 201 includes a combination of three colors, and each pixel unit 201 has three single pixel units, namely a first single pixel unit 2011, a second single pixel unit 2012, and a third single pixel unit 2013. Figure 2 As shown in (d) in .

[0053] In order to realize the display of different colors, some embodiments of the present application provide a reflective display device. Figure 1Each pixel unit 201 in the display panel shown can be provided with a plurality of reflective display devices, and each reflective display device displays one color. That is, in the embodiment of the present application, the first single pixel unit 2011, the second single pixel unit 2012, and the third single pixel unit 2013 can all adopt a reflective display device provided by the embodiment of the present application. Taking each pixel unit 201 displaying three different colors as an example, generally, red, green, and blue are selected to realize the color combination. In order to enable each pixel unit 201 to display three different colors, each pixel unit 201 includes three reflective display devices, that is, the first single pixel unit 2011 corresponds to the first reflective display device, which is used to display one color, such as red; the second single pixel unit 2012 corresponds to the second reflective display device, which is used to display another color, such as green; and the third single pixel unit 2013 corresponds to the third reflective display device, which is used to display another color, such as blue.

[0054] In order to make the first reflective display device, the second reflective display device and the third reflective display device corresponding to each color pixel unit display different colors, for example, red, green and blue, respectively, antenna arrays with different antenna widths and array periods can be arranged between the first reflective display device, the second reflective display device and the third reflective display device. The antenna array can be a structural component for color display in the reflective display device.

[0055] Figure 3 A top view of a reflective display device provided in an embodiment of the present application, Figure 4 This is a schematic diagram of a reflective display device provided in an embodiment of the present application. Figure 3 and Figure 4 , a reflective display device includes a substrate 301, an antenna array 302 and a control circuit 303.

[0056] The substrate 301 is made of a transparent material, or at least the side of the substrate 301 close to the antenna array 302 is made of a transparent material to improve the reflection efficiency of ambient light. It should be understood that the imaginary part of the refractive index of the material used for the substrate 301 is low to avoid loss of the optical mode in the array. The substrate 301 plays a supporting role in the reflective display device. For example, the substrate 301 can be made of glass.

[0057] The antenna array 302 is disposed on one side of the substrate 301 , and includes a dielectric material array 3021 arranged periodically and an electrochromic material film 3022 covering the surface of the dielectric material array 3021 ; the dielectric material array 3021 is used to reflect visible light to form a reflection peak.

[0058] It should be noted that the dielectric material array 3021 is nano-scale, and the dielectric material array 3021 can be composed of nano-dielectric material structures of different shapes and sizes in a regular arrangement, such as a square array, a hexagonal array, etc. The dielectric material array 3021 can also be arranged according to any rules according to specific display requirements. In the antenna array 302, each antenna, that is, the nano-dielectric material structure can adopt a three-dimensional structure of a cube, a cylinder, or other shapes.

[0059] For the dielectric material in the dielectric material array 3021, various optical dielectric materials can be selected, which meet the characteristics of having a higher refractive index and lower loss. Among them, lower loss means that the imaginary part of the refractive index is lower. Optionally, the refractive index of the material of the dielectric material array 3021 is greater than the refractive index of the material of the substrate 301. In this way, the large refractive index contrast enables the antenna array 302 to generate a sufficiently strong local mode of the light field to support a reflection peak with high reflectivity and narrow bandwidth. For example, the real part of the refractive index of the material of the dielectric material array 3021 is greater than 2, and the real part of the refractive index of the material of the substrate 301 is less than 2. The material of the dielectric material array 3021, for example, silicon, silicon nitride, gallium nitride, titanium dioxide, etc. It should be understood that the material of the dielectric material array 3021 can also be selected from a composite dielectric material composed of multiple dielectric materials, such as a composite dielectric material composed of silicon nitride and titanium dioxide.

[0060] The dielectric material array 3021 can support electric dipole resonance and magnetic dipole resonance modes in the visible light band, and can form a limited bandwidth reflection at a specific spectral wavelength position, that is, a reflection peak with high reflectivity and narrow bandwidth is generated. By adjusting the geometric parameters of the dielectric material array 3021, such as the period, lateral width, height and arrangement of the dielectric material array 3021, the limited bandwidth reflection position, that is, the position of the spectral wavelength, can be changed. Different spectral wavelength positions can correspond to different color displays, that is, to different structural colors.

[0061] It should be understood that the period of the dielectric material array 3021 refers to the distance between two adjacent dielectric material structures, such as the distance from the leftmost endpoint of the i-th dielectric material structure to the leftmost endpoint of the i+1-th dielectric material structure. The lateral width of the dielectric material array 3021 refers to the distance from the leftmost endpoint to the rightmost endpoint in the i-th dielectric material structure.

[0062] The lateral width of a single dielectric material structure in the dielectric material array 3021 in the present application is in the order of hundreds of nanometers, so as to effectively improve the resolution of the reflective display device.

[0063] In addition, the electrochromic material film 3022 is arranged on the surface of the dielectric material array 3021, and together with the dielectric material array 3021, it constitutes the antenna array 302. In the reflective display device in the embodiment of the present application, the nanometer-scale antenna array 302 can support the optical resonance mode and realize the reflection peak with high reflectivity and narrow bandwidth. The optical resonance mode forms a higher light field enhancement in the local area of ​​the surface of the dielectric material array 3021, which can effectively enhance the interaction between the electrochromic material film 3022 covered on the surface and the light field, so only a very thin electrochromic material is required to realize the modulation of light, and the thickness of the electrochromic material film 3022 can be less than 50nm, which helps to improve the modulation rate of the electrochromic material and improve the display performance. In other words, the thickness of the electrochromic material film 3022 is a nanometer-scale thickness. When performing optical modulation, the thinner the thickness of the electrochromic material film 3022, the better the adjustment effect of the imaginary part of the refractive index of the electrochromic material film 3022, and the faster the response speed. Furthermore, a very strong local electromagnetic field will be generated around the dielectric material array 3021 due to the resonance effect, which can further improve the adjustment effect and response speed of the imaginary part of the refractive index of the electrochromic material.

[0064] Since the optical absorptivity of the electrochromic material can change under the action of an external electric field, the imaginary part of the refractive index of the electrochromic material can change under the control of an electrical signal. The change of the imaginary part of the refractive index can actually be understood as the change of the optical absorptivity of the electrochromic material. That is, when the imaginary part of the refractive index of the electrochromic material changes, the electrochromic material can continuously change between no optical loss, low optical loss and high optical loss.

[0065] It should also be noted that when the imaginary part of the refractive index of the electrochromic material film 3022 increases, it behaves as a material with optical loss, so that the resonant mode supported by the antenna array 302 is attenuated, the coupling with the incident light is weakened, and the reflectivity of the antenna array 302 is reduced, which is manifested as a reduction in the brightness of the structural color.

[0066] In order to control the change of the imaginary part of the refractive index of the electrochromic material film 3022, a corresponding electrical signal can be applied to the electrochromic material film 3022 for control, and the electrical signal can be output by the control circuit 303. The control circuit 303 is connected to the electrochromic material film 3022 through a conductive material, so as to adjust the imaginary part of the refractive index of the electrochromic material film 3022, thereby adjusting the reflection peak formed by the dielectric material array 3021 to visible light. For example, a first conductive layer 304 is provided between the dielectric material array 3021 and the electrochromic material film 3022, and a second conductive layer 305 is provided on the side of the electrochromic material film 3022 away from the dielectric material array 3021. The control circuit 303 can connect the electrochromic material film 3022 through the first conductive layer 304 and the second conductive layer 305 to adjust the imaginary part of the refractive index of the electrochromic material film 3022.

[0067] Figure 5 A schematic structural diagram of another reflective display device provided in an embodiment of the present application. Figure 5 The structure and Figure 4 The difference between the structures in the reflective display device in the embodiment is that the thickness of the second conductive layer 305 is inconsistent. In the reflective display device provided in the present application, only a thinner layer of conductive material is needed as the second conductive layer 305 to meet the display requirements of the reflective display device. Therefore, the first conductive layer 304 and the second conductive layer 305 can both be a thinner layer of conductive material.

[0068] The following is a specific process of the control circuit 303 controlling the imaginary part of the refractive index of the electrochromic material film 3022 to adjust the reflection peak formed by the dielectric material array 3021 to the visible light:

[0069] The control circuit 303 outputs a corresponding electrical signal according to specific display requirements. Under the control of the electrical signal, when the imaginary part of the refractive index of the electrochromic material is zero, that is, the absorptivity of the electrochromic material is zero, light is incident on the antenna array 302 to form a limited bandwidth reflection, which is manifested as a high reflection peak at a specific wavelength position. At this time, the reflectivity is the highest, and it is visually manifested as a specific color with high brightness; however, under the control of the electrical signal, when the imaginary part of the refractive index of the electrochromic material is gradually increased, the absorptivity of the electrochromic material increases, the reflectivity of the antenna array 302 decreases, and the reflection peak at the specific wavelength position gradually decreases, which is visually manifested as a specific color with low brightness; under the control of the electrical signal, after the imaginary part of the refractive index of the electrochromic material is increased to a certain extent, the reflectivity of the antenna array 302 is reduced to the minimum, and it is visually manifested as a very low brightness, forming black. Therefore, through the control of the electrical signal, the imaginary part of the refractive index of the electrochromic material can be adjusted to adjust the brightness of the color reflected by the antenna array 302, and the display of various colors can be realized by using the principle of additive color.

[0070] The electrochromic material in the embodiment of the present application may be a transition metal oxide such as tungsten trioxide (WO3) or nickel oxide (NiO), or an organic polymer such as polyaniline, which is not limited in the embodiment of the present application.

[0071] In addition, since the electrochromic material has a bistable characteristic, the state of the electrochromic material when the optical loss changes can be maintained continuously. Therefore, the electrochromic material does not need to continuously apply an electrical signal to maintain the state. Therefore, the electrochromic material does not need to continuously consume energy when achieving brightness adjustment, thereby reducing the energy consumption of the entire display device.

[0072] In the reflective display device, in the antenna array 302, different antenna widths and different array periods can enable the dielectric material array 3021 to support different optical resonance modes, and can form limited bandwidth reflection at a specific spectral wavelength position.

[0073] Figure 6 A schematic diagram of a pixel unit composed of three reflective display devices is provided in an embodiment of the present application. Figure 6 In the embodiment, three reflective display devices with different periods and different antenna widths together constitute a pixel unit 201, namely a color pixel unit. The three different reflective display devices can respectively reflect to form different structural colors, for example, they can respectively correspond to blue, green and red.

[0074] The three different reflective display devices are controlled by independent control circuits 303 respectively. Figure 7 A reflective display device reflection spectrum waveform provided in an embodiment of the present application Figure 1 . Figure 7 The waveform diagrams correspond to the case where the imaginary part of the refractive index of the electrochromic material film 3022 in three different reflective display devices is zero, wherein Figure 7 The S1 waveform in the figure represents blue, the S2 waveform represents green, and the S3 waveform represents red. It can be seen that Figure 7 The reflectivity corresponding to each color is relatively high, and the electrochromic material film 3022 behaves as a material without optical loss. At this time, the brightness of each color is also the highest.

[0075] also, Figure 8 A reflective display device reflection spectrum waveform provided in an embodiment of the present application Figure 2 . Figure 7 The waveform diagrams correspond to the situation where the imaginary part of the refractive index of the electrochromic material film 3022 in the three different reflective display devices increases to a certain extent, wherein Figure 7 The S1 waveform in the figure represents blue, the S2 waveform represents green, and the S3 waveform represents red. It can be seen that Figure 7The reflectivity corresponding to each color is very low, and the electrochromic material film 3022 appears as a material with optical loss. At this time, the brightness of each color is the lowest, and visually appears to be black.

[0076] Therefore, please refer to Figure 2 As shown in the schematic diagram, a pixel unit 201, i.e., a color pixel unit, is formed by reflective display devices of different colors, and the color pixel units are arranged periodically to form a color display panel. The brightness of each pixel unit 201 is adjusted by independent control of the control circuit 303 in the different reflective display devices in each pixel unit 201, thereby realizing the display of a color image.

[0077] The following is an example of a reflective structure device.

[0078] Fig. 9 A schematic diagram of a specific example of a reflective display device provided in an embodiment of the present application. Fig. 9 In the embodiment, the reflective display device includes a substrate 301, which is a glass substrate and mainly plays a supporting role. The material of the substrate 301 is silicon dioxide, and the refractive index of silicon dioxide in the visible light range is 1.46. An antenna array 302 is arranged above the substrate 301. Each antenna unit in the antenna array 302 is in the shape of a terrace, and the angle between the waist of the terrace and the bottom is 70 degrees. The dielectric materials selected by the dielectric material array 3021 in the antenna array 302 are silicon nitride and titanium dioxide, wherein the refractive index of silicon nitride is 2, and the refractive index of titanium dioxide is 2.45. A first conductive layer 304 with a thickness of 10 nanometers is covered above the dielectric material array 3021 as a conductive electrode; the material of the first conductive layer 304 is indium tin oxide, which is a transparent material with a refractive index of 1.37. A layer of organic electrochromic material polyaniline (PANI) with a thickness of 30 nanometers is covered above the first conductive layer 304 as an electrochromic material film 3022. The second conductive layer 305 is covered on the organic electrochromic material, and the second conductive layer 305 can also be made of indium tin oxide; and an electrolyte layer 306 is arranged between the electrochromic material film 3022 and the second conductive layer 305, and the refractive index of the electrolyte layer 306 is 1.33, which is more conducive to the conductivity of the second conductive layer 305. It should be understood that the electrolyte layer 306 here is optional, and not arranging the electrolyte layer 306 does not affect the realization of the actual function.

[0079] exist Fig. 9In the reflective structure device shown, the control circuit 303 is first used to control the electrochromic material film 3022 in the reflective structure device to be in the first state, that is, the real part of the refractive index is 1.37 and the imaginary part of the refractive index is 0. The height of the antenna array 302 is fixed, and by adjusting the width w of the antenna array 302, the array period p of the antenna array 302 can change the position of the spectral wavelength (wavelength) of the emission peak generated by the visible light reflected by the antenna array 302. The position of the changed spectral wavelength can correspond to different structural colors. Please refer to Fig.10 .

[0080] Fig.10 Schematic diagram showing reflection spectra formed by different antenna array structures. Fig.10 When the array period p of the antenna array 302 is 290 nanometers and the antenna width w of the antenna array 302 is 230 nanometers, the reflection peak is formed at a position where the spectrum wavelength is approximately 450 nanometers, and the reflectance is above 90%. At this time, the structural color displayed is blue. The reflective display device formed by the antenna array 302 can be used as Figure 2 The third reflective display device in (d).

[0081] When the array period p of the antenna array 302 is 340 nanometers and the antenna width w of the antenna array 302 is 285 nanometers, the reflection peak is formed at a position where the spectral wavelength is approximately 550 nanometers, the reflectivity is above 80%, and the structural color displayed at this time is green. The reflective display device formed by the antenna array 302 at this time can be used as Figure 2 The second reflective display device in (d).

[0082] When the array period p of the antenna array 302 is 400 nanometers and the antenna width w of the antenna array 302 is 300 nanometers, the reflection peak is formed at a position where the spectral wavelength is approximately 600 nanometers, and the reflectivity is above 80%. At this time, the structural color displayed is red. The reflective display device formed by the antenna array 302 at this time can be used as Figure 2 The first reflective display device in (d).

[0083] Fig.11 for Fig.10 The coordinate diagram of the structural color shown by the reflectance spectrum in the CIE1931 chromaticity diagram. Point A represents green, point B represents blue, and point C represents red. The three points A, B, and C are connected to form a triangle, and the area of ​​the triangle is Figure 6 The color gamut range that the reflective device can cover. It can be seen that the color gamut covered by points A, B, and C is large and can support various reflective display application scenarios.

[0084] It should be understood that Fig.11 In the CIE1931 chromaticity diagram shown, the horizontal axis x is the proportion of the red component in the three primary colors (red, green, and blue), and the vertical axis y is the proportion of the green component in the three primary colors (red, green, and blue). In this CIE1931 chromaticity diagram, the sum of the proportions of the red component, green component, and blue component in each color should be equal to 1.

[0085] Fig.12 for Fig. 9 The reflection spectra of the imaginary part of the refractive index of the electrochromic material film 3022 in the three structures when k = 0.05, k = 0.2 and k = 1 are as follows: Fig.12 As shown in , as the imaginary part of the refractive index of the electrochromic material film 3022 increases, the height of the reflection peak in the reflection spectrum corresponding to each structural color decreases. When the imaginary part of the refractive index of the electrochromic material film 3022 k=1, the height of the reflection peak in the reflection spectrum corresponding to each structural color decreases to the minimum, that is, the antenna array 302 structure shows an extremely low emissivity in the entire visible light band, corresponding to the closure of the brightness of the corresponding structural color. Therefore, by adjusting the imaginary part of the refractive index of the electrochromic material film 3022, the brightness of the structural color formed after the visible light is emitted on the antenna array 302 can be adjusted.

[0086] For color display, you can Fig. 9 The reflective display device shown is combined and arranged according to the corresponding antenna width and antenna array period to form a color pixel unit 201, for example Figure 2 As shown in (c) and (d), each reflective device has an independent control circuit 303, and the color brightness of the light reflected by the corresponding reflective device can be controlled by the control circuit 303. By utilizing the principle of color addition and mixing three or more colors, reflective displays of various colors can be achieved.

[0087] In addition, if the energy consumption of the reflective display device is not taken into account, if the switching speed of the device is increased, the proportion of the device in the on or off state in the time dimension can be controlled, and the visual persistence effect of the human eye can be used to control the brightness of the structural color. In other words, the reflective display device is set to two states, one is the bright state display of a specific color, at this time the brightness of the color is the highest; the other is the dark state display of a specific color, at this time the brightness of the color is the lowest. The brightness of the displayed color is controlled by the time ratio of the bright state display and the dark state display of a specific color. For example, within a time period, the ratio of the time of the bright state display and the dark state display of a specific color is 1:1, and the color brightness that can be perceived by the human eye is 50%.

[0088] Regarding image display, the present application also provides a method for controlling image display. Fig.13 FIG. 1 is a flowchart of an image display control method provided by an embodiment of the present application. The image display control method can be applied to Figure 1 Display screen 01 shown.

[0089] Please refer to Fig.13 ,by Figure 2 The corresponding display principle, and Figure 4 or Figure 5 Taking the reflective display device as an example, the image display control method includes:

[0090] S1301, the display driver receives an image display signal. When performing image display, the display driver receives the image display signal, and the image display signal includes pixel information of the image to be displayed. In the display panel of the display screen 01, each reflective display device can control the brightness display of the color through the control circuit 303 according to the corresponding pixel information, thereby realizing the display of the color in each pixel unit 201.

[0091] S1302, the display driver sends a display control signal to the control circuit 303 of each reflective display device in each pixel unit 201 according to the image display signal. The brightness adjustment of the reflective display device is controlled by the control circuit 303. When the display driver receives the image display signal, the display driver sends a display control signal to the control circuit 303 of each reflective display device in the corresponding pixel unit 201 according to the pixel information in the image display signal, and the display control circuit 303 adjusts the imaginary part of the refractive index of the electrochromic material film 3022 in the corresponding reflective display device.

[0092] S1303, the control circuit 303 adjusts the imaginary part of the refractive index of the electrochromic material film 3022 in each reflective display device according to the display control signal to adjust the brightness of each reflective display device. Generally, the imaginary part of the refractive index of the electrochromic material film 3022 in the reflective display device is controlled by voltage. When different voltages are applied to the electrochromic material film 3022, the size of the imaginary part of the refractive index of the electrochromic material film 3022 is different, and the optical loss exhibited by the electrochromic material film 3022 during optical reflection is different. Therefore, when the control circuit 303 receives the display control signal, the control circuit 303 outputs a control voltage to adjust the imaginary part of the refractive index of the electrochromic material film 3022 in each display device to adjust the reflection peak formed by the dielectric material array to the visible light.

[0093] S1304, when the control circuit 303 completes the imaginary part condition of the refractive index of the electrochromic material film 3022 in the display device during emission, the display panel displays the image corresponding to the image display signal.

[0094] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art who is familiar with the present technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

Claims

1. A reflective display device, characterized in that: include: substrate; An antenna array is disposed on one side of the substrate; The antenna array supports an optical resonance mode; the antenna array comprises a dielectric material array arranged periodically and an electrochromic material film covering the surface of the dielectric material array; the dielectric material array is used to reflect visible light to form a reflection peak; the electrochromic material film has a thickness of less than 50 nm; The control circuit is connected to the electrochromic material film through a conductive material and is used to adjust the imaginary part of the refractive index of the electrochromic material film to adjust the reflection peak formed by the dielectric material array to visible light.

2. The reflective display device according to claim 1, characterized in that: A first conductive layer is arranged between the dielectric material array and the electrochromic material film; a second conductive layer is arranged on a side of the electrochromic material film away from the dielectric material array, and both the first conductive layer and the second conductive layer are connected to a control circuit.

3. The reflective display device according to claim 1 or 2, characterized in that: The refractive index of the material of the dielectric material array is greater than the refractive index of the material of the substrate.

4. The reflective display device according to claim 1 or 2, characterized in that: The side of the substrate on which the antenna array is arranged is made of transparent material.

5. The reflective display device according to claim 1 or 2, characterized in that: The material of the dielectric material array includes one or more of silicon, silicon nitride, gallium nitride and titanium dioxide.

6. A display panel, characterized in that: It comprises a plurality of pixel units, the plurality of pixel units are arranged periodically, and each of the pixel units comprises a plurality of reflective display devices; the reflective display device is the reflective display device as claimed in any one of claims 1 to 5.

7. The display panel according to claim 6, characterized in that: Each of the pixel units includes at least three reflective display devices; wherein, in different reflective display devices, the antenna widths in the antenna array are different, and the array periods of the antenna array are different.

8. A display screen, characterized in that: It comprises a display driver and a display panel as claimed in claim 6 or 7, wherein the display driver is connected to the display panel and is used to control the display panel to perform image display.

9. An image display control method, characterized in that: Applied to a display screen, the display screen comprises a display driver and a display panel, the display driver is connected to the display panel and is used to control the display panel to perform image display; The display panel comprises a plurality of pixel units, the plurality of pixel units are arranged periodically, and each of the pixel units comprises a plurality of reflective display devices; The reflective display device comprises: substrate; An antenna array is arranged on one side of the substrate; the antenna array supports an optical resonance mode; the antenna array comprises a dielectric material array arranged periodically and an electrochromic material film covering the surface of the dielectric material array; the dielectric material array is used to reflect visible light to form a reflection peak; the electrochromic material film has a thickness of less than 50 nm; A control circuit, connected to the electrochromic material film via a conductive material, for adjusting the imaginary part of the refractive index of the electrochromic material film to adjust the reflection peak formed by the dielectric material array to visible light; The method comprises: The display driver receives an image display signal; The display driver sends a display control signal to a control circuit of each reflective display device in each pixel unit according to the image display signal; The control circuit adjusts the imaginary part of the refractive index of the electrochromic material film in each of the reflective display devices according to the display control signal, so as to adjust the brightness of each of the reflective display devices; The display panel displays an image corresponding to the image display signal.

10. The image display control method according to claim 9, characterized in that: The control circuit adjusts the imaginary part of the refractive index of the electrochromic material film in each of the reflective display devices according to the display control signal, including: The control circuit outputs a control voltage, the control voltage is determined according to the display control signal, and the control voltage is used to adjust the imaginary part of the refractive index of the electrochromic material film in each of the display devices.

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