WO2024198400A1 - Display panel and display device - Google Patents

Abstract

A display panel and a display device. The display panel comprises a display control unit (210), a view angle control unit (220), and a heating unit (230); the heating unit (230) controls, in a first display mode, the temperature of the view angle control unit (220) to be greater than a clearing point of a liquid crystal; and the viewing angle of the display panel in the corresponding first display mode is greater than the viewing angle in a second display mode.

Description

Display panel and display device Technical Field

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

Background Art

Setting up an anti-peeping device on the display panel can make the information at a large angle invisible and protect the privacy of information; it can also prevent the virtual image from being projected onto the front windshield and side windows, increasing the safety of vehicle driving. The existing anti-peeping device can be implemented by means of an electrophoretic light modulator. However, the electrophoretic light modulator switches between a light-transmitting mode and a non-light-transmitting mode to achieve the display and non-display effects, and cannot achieve the switching between narrow and wide viewing angle modes, so it is not suitable for application on display panels.

SUMMARY OF THE INVENTION

Embodiments of the present application provide a display panel and a display device, which can achieve mode switching between wide viewing angle and narrow viewing angle.

The embodiment of the present application provides a display panel, including a display control unit, a viewing angle control unit and a heating unit. The display control unit includes a color filter substrate and a first polarizer located on the color filter substrate. The viewing angle control unit is located between the color filter substrate and the first polarizer, and the viewing angle control unit includes liquid crystal; the heating unit is configured to control the temperature of the viewing angle control unit to be greater than the clearing point of the liquid crystal in a first display mode. The visible viewing angle of the display panel in the first display mode is greater than the visible viewing angle of the display panel in the second display mode.

The present application also provides a display device, comprising any of the above-mentioned display panels and a backlight module; wherein the backlight module is located on a side of the color film substrate away from the viewing angle control unit.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG1 is a schematic diagram of the structure of an electrophoretic light modulator in the prior art;

2A and 2B are schematic diagrams of the structure of a display panel provided in an embodiment of the present application;

FIG. 3 is a schematic diagram of the structure of a display device provided in an embodiment of the present application.

Embodiments of the present invention

In order to make the purpose, technical solution and effect of the present application clearer and more specific, the present application is further described in detail with reference to the accompanying drawings and examples. It should be understood that the specific examples described here are only used to explain the present application and are not used to limit the present application.

Optionally, in some embodiments of the present application, the heating unit includes a heating resistor, and the heating resistor is located between the viewing angle control unit and the color filter substrate.

Optionally, in some embodiments of the present application, the display color filter substrate includes a color filter, and the color filter includes a plurality of color filter units and a black matrix located between the plurality of color filter units. The orthographic projection of the heating resistor on the color filter coincides with the black matrix.

Optionally, in some embodiments of the present application, the viewing angle control unit further includes a first alignment layer and a second alignment layer, wherein the first alignment layer is located between the heating resistor and the liquid crystal, and the second alignment layer is located between the liquid crystal and the first polarizer.

Optionally, in some embodiments of the present application, the viewing angle control unit further includes a first electrode layer and a second electrode layer, wherein the first electrode layer is located between the heating resistor and the liquid crystal, and the second electrode layer is located between the liquid crystal and the first polarizer.

Optionally, in some embodiments of the present application, the wavelength dispersion of the birefringence of the liquid crystal is positive dispersion.

Optionally, in some embodiments of the present application, the clearing point of the liquid crystal is not equal to the ambient temperature of the display panel.

Optionally, in some embodiments of the present application, the clearing point of the liquid crystal is greater than the ambient temperature of the display panel.

Optionally, in some embodiments of the present application, the display control unit includes an array substrate, a second polarizer, and a display liquid crystal layer. The array substrate is located on a side of the color filter substrate away from the viewing angle control unit, the second polarizer is located on a side of the array substrate away from the color filter substrate, and the display liquid crystal layer is located between the array substrate and the color filter substrate.

The present application provides a display panel and a display device, wherein the display panel includes a display control unit, a viewing angle control unit and a heating unit. The display control unit includes a color film substrate and a first polarizer located on the color film substrate. The viewing angle control unit is located between the color film substrate and the first polarizer, and the viewing angle control unit includes liquid crystal; the heating unit is configured to control the temperature of the viewing angle control unit to be greater than the clearing point of the liquid crystal in the first display mode, so that the liquid crystal is converted into a liquid state in the first display mode and has isotropy, so that the liquid crystal has no effect on the polarization state of light in all directions, and then the display panel has a larger visual viewing angle in the first display mode. In the second display mode of the display panel, the heating unit is not used to make the temperature of the viewing angle control unit greater than the clearing point of the liquid crystal, so that the liquid crystal has anisotropy, so that the liquid crystal causes different degrees of phase delay to the light of each wavelength in part of the light, so that the light of the display panel corresponding to the phase delay has light leakage and color deviation problems after passing through the first polarizer. Therefore, the visual viewing angle of the display panel corresponding to the first display mode can be made greater than the visual viewing angle of the display panel corresponding to the second display mode, so as to realize the mode switching of the narrow viewing angle and the wide viewing angle of the display panel. The display device includes any of the above-mentioned display panels and backlight modules.

Specifically, FIG. 1 is a schematic diagram of the structure of an electrophoretic light modulator in the prior art, and the electrophoretic light modulator includes a first optical substrate 101, a second optical substrate 102, an electrophoretic ink 103 and a spacer 104 encapsulated between the first optical substrate 101 and the second optical substrate 102. The first optical substrate 101 includes a patterned first electrode 1011, and the second optical substrate 102 includes a patterned second electrode 1021. The first electrode 1011 and the second electrode 1021 are arranged in an interdigitated structure, and the first electrode 1011 and the second electrode 1021 are configured to generate an electric field to induce the electrophoretic pigment contained in the electrophoretic ink to move in all directions. When an electric field is not generated between the first electrode 1011 and the second electrode 1021, light is restricted and cannot be transmitted. When an electric field is generated between the first electrode 1011 and the second electrode 1021, light is allowed to be transmitted. When the interface window of the electrophoretic modulator is manipulated, the electrophoretic pigment is aligned between the first electrode 1011 and the second electrode 1021, so that it is displayed as hidden within the normal viewing angle range. The electrophoretic pigment can be driven by a low-frequency AC signal so that the electrophoretic pigment is in a stable state at the first electrode 1011 and the second electrode 1021 .

Since the electrophoretic light modulator switches between the light-transmitting mode and the light-non-transmitting mode to achieve the switching between the display mode and the non-display mode, the electrophoretic light modulator cannot achieve the mode switching between the narrow viewing angle and the wide viewing angle, and therefore is not suitable for application in display panels.

2A and 2B are schematic diagrams of the structure of the display panel provided in the embodiment of the present application. FIG2A is a schematic diagram of the structure of the display panel provided in the embodiment of the present application in the first display mode, and FIG2B is a schematic diagram of the structure of the display panel provided in the embodiment of the present application in the second display mode.

The embodiment of the present application provides a display panel, which includes a display control unit 210 , a viewing angle control unit 220 and a heating unit 230 .

Optionally, the display control unit 210 is configured to control a display state of the display panel (ie, the display control unit 210 controls the display panel to display or controls the display panel not to display).

Optionally, the display panel includes a passive light-emitting display panel, etc. Optionally, the passive light-emitting display panel includes a liquid crystal display panel, etc.

Optionally, the display control unit 210 includes a color filter substrate 211 and a first polarizer 212 . The first polarizer 212 is located on the color filter substrate 211 .

Optionally, the display control unit 210 further includes an array substrate 213, a display liquid crystal layer 214, and a second polarizer 215. The array substrate 213 is located on a side of the color filter substrate 211 away from the first polarizer 212, the second polarizer 215 is located on a side of the array substrate 213 away from the color filter substrate 211, and the display liquid crystal layer 214 is located between the array substrate 213 and the color filter substrate 211.

Optionally, the array substrate 213 includes a first substrate, a pixel driving circuit, a scan line, a data line, a pixel electrode, a first display alignment layer, etc. The pixel driving circuit is located on the first substrate, and the scan line and the data line are electrically connected to the pixel driving circuit, so that the pixel driving circuit forms an electric field between the pixel electrode and the common electrode of the display panel according to the scan signal transmitted by the scan line and the data signal transmitted by the data line, thereby controlling the deflection state of the liquid crystal molecules included in the display liquid crystal layer 214, and then controlling the display panel to display or not display.

Optionally, the first substrate includes a rigid substrate, a flexible substrate, etc.; the pixel driving circuit may be in the form of 2T1C (i.e., 2 transistors and 1 capacitor), 5T2C, 7T1C, etc.; the pixel driving circuit includes transistors, and the transistors include silicon semiconductors, oxide semiconductors, etc.

Optionally, the color filter substrate 211 includes a second substrate and a second display alignment layer, wherein the second display alignment layer is located on a side of the second substrate close to the display liquid crystal layer 214 .

Optionally, the display control unit 210 further includes a color filter. The color filter includes a plurality of color filter units and a black matrix located between the plurality of color filter units. Optionally, the array substrate 213 includes the color filter or the color film substrate 211 includes the color filter.

Optionally, the common electrode of the display panel may be arranged on the color filter substrate 211 side or on the array substrate 213 side.

Optionally, the common electrode and the pixel electrode are both arranged on the side of the array substrate 213, so that the electric field formed between the pixel electrode and the common electrode is a transverse electric field, so that the liquid crystal molecules contained in the display liquid crystal layer 214 are parallel to the display plane of the display panel regardless of whether they are in an electric field state or not, thereby enabling the display panel to have a larger visual viewing angle in the first display mode.

Please continue to refer to Figures 2A to 2B. The viewing angle control unit 220 is located between the color film substrate 211 and the first polarizer 212. The viewing angle control unit 220 is configured to control the display mode of the display panel (that is, the viewing angle control unit 220 controls the display panel to be in a first display mode with a larger visible viewing angle, or the viewing angle control unit 220 controls the display panel to be in a second display mode with a smaller visible viewing angle).

Optionally, the viewing angle control unit 220 includes a liquid crystal 221. The viewing angle control unit 220 controls the display mode of the display panel by switching between a liquid crystal state and a liquid state of the liquid crystal 221.

Optionally, the liquid crystal 221 may be switched between a liquid crystal state and a liquid state by controlling the temperature of the viewing angle control unit 220 .

Please continue to refer to FIG. 2A , the heating unit 230 is configured to control the temperature of the viewing angle control unit 220 to be greater than the clearing point of the liquid crystal 221 in the first display mode, so that the liquid crystal 221 is transformed into a liquid state in the first display mode and has isotropy, so that the liquid crystal 221 has no effect on the polarization state of light in all directions, and then the visual viewing angle of the display panel in the first display mode is larger. The liquid crystal 221 in FIG. 2A is in a transparent state after the temperature of the viewing angle control unit 220 is greater than the clearing point.

To facilitate understanding of the principle that the display panel has a smaller visual angle in the second display mode, it is assumed that when the liquid crystal 221 is in a liquid crystal state and has anisotropy, the liquid crystal 221 is in a vertical arrangement. On this basis, please continue to refer to FIG. 2B. In the second display mode of the display panel, the heating unit 230 is not used to make the temperature of the viewing angle control unit 220 greater than the clearing point of the liquid crystal 221. Therefore, the liquid crystal 221 is in a liquid crystal state and has anisotropy, and the liquid crystal 221 is in a vertical arrangement. The liquid crystal 221 does not cause phase delay to the light of each wavelength of the first light (such as a vertical light parallel to the long axis of the liquid crystal 221 and perpendicular to the display surface of the display panel), so that the display effect of the display panel corresponding to the vertical light is not affected. When the liquid crystal 221 is in a liquid crystal state and has anisotropy, the liquid crystal 221 will cause different degrees of phase delay to the light of each wavelength of the second light (such as the oblique light) (such as the liquid crystal 221 will produce a larger phase shift to the blue light with a shorter wavelength in the oblique light, and a smaller phase shift to the red light with a longer wavelength), so that the light with phase delay passes through the first polarizer and the display panel is viewed at a viewing angle outside the narrow viewing angle. The light with phase delay also increases the degree of light leakage within the viewing angle outside the narrow viewing angle after passing through the first polarizer, thereby reducing the contrast of the display panel, so that the display panel displays the picture normally within the range of the corresponding narrow viewing angle, while the display picture corresponding to the viewing angle outside the narrow viewing angle has a color shift. Therefore, the visible viewing angle of the display panel corresponding to the first display mode can be greater than the visible viewing angle of the display panel corresponding to the second display mode, so as to achieve the mode switching of the narrow viewing angle and the wide viewing angle of the display panel.

The heating unit 230 is not used to make the temperature of the viewing angle control unit 220 greater than the clearing point of the liquid crystal 221, which may mean that the heating unit 230 controls the temperature of the viewing angle control unit 220 to be less than the clearing point of the liquid crystal 221, or that the heating unit 230 does not participate in the process of the viewing angle control unit 220 changing from a temperature value greater than the clearing point of the liquid crystal 221 to another temperature value less than the clearing point of the liquid crystal 221. The second light is light other than the first light.

The present application controls the dispersion of wide-viewing angle light so that the display panel has a wide-viewing angle display effect in the first display mode and a narrow-viewing angle display effect in the second display mode. Therefore, the display panel can achieve controllable and anti-peeping display viewing angle.

It can be understood that the viewing angle control unit 220 is located between the color filter substrate 211 and the first polarizer 212 , so that the array substrate 213 is correspondingly located on a side of the color filter substrate 211 away from the viewing angle control unit 220 .

Optionally, the heating unit 230 may include a heating resistor, which is located between the viewing angle control unit 220 and the color film substrate 211, so as to control the temperature of the viewing angle control unit 220 to be greater than the clearing point through the heating resistor, thereby realizing the conversion of the liquid crystal 221 from a liquid crystal state to a liquid state, thereby placing the display panel in the first display mode, as shown in FIG. 2A.

Optionally, a voltage may be applied to the heating resistor to drive the heating resistor to heat the liquid crystal 221 , thereby causing the liquid crystal 221 to switch from a liquid crystal state to a liquid state.

Optionally, when the heating unit 230 is not used to make the temperature of the viewing angle control unit 220 greater than the clearing point of the liquid crystal 221 , no voltage is applied to the heating resistor, so that the display panel does not drive the heating resistor to heat the liquid crystal 221 .

Optionally, the clearing point of the liquid crystal 221 is not equal to the ambient temperature of the display panel, so that the display panel is in one of a first display mode and a second display mode at the ambient temperature.

Optionally, the clearing point of the liquid crystal 221 is greater than the ambient temperature of the display panel, so that when the heating resistor does not heat the liquid crystal 221, the liquid crystal 221 can be converted from the liquid state to the liquid crystal state according to the ambient temperature of the display panel.

Optionally, the clearing point of the liquid crystal 221 may also be lower than the ambient temperature of the display panel, so that the liquid crystal 221 is in the liquid state at the ambient temperature of the display panel. Accordingly, when the clearing point of the liquid crystal 221 is lower than the ambient temperature of the display panel, the heating unit 230 is used to control the temperature of the viewing angle control unit 220 to be lower than the clearing point of the liquid crystal 221, so that the liquid crystal 221 is converted from the liquid state to the liquid crystal state.

Optionally, in order to reduce the influence of the heating resistor on the aperture ratio of the display panel, the orthographic projection of the heating resistor on the display control unit 210 coincides with the black matrix.

Optionally, the orthographic projection of the heating resistor on the display control unit 210 coincides with a scan line and/or a data line, so as to reduce the influence of the heating resistor on the aperture ratio of the display panel.

Optionally, the orthographic projection of the heating resistor on the display control unit 210 is evenly distributed, so that when the heating unit 230 is used to make the temperature of the viewing angle control unit 220 greater than the clearing point of the liquid crystal 221, the liquid crystal 221 at each location in the viewing angle control unit 220 is heated evenly, thereby ensuring the display effect of the display panel in the first display mode.

Optionally, the orthographic projections of the heating resistors on the display control unit 210 are distributed in a strip matrix.

Optionally, the heating unit 230 may also use the Peltier effect to set up an electrical circuit formed by multiple (such as two) different materials (semiconductors and/or metals), and energize the electrical circuit to control the temperature of the viewing angle control unit 220 to be greater than the clearing point of the liquid crystal 221, so that the liquid crystal 221 is converted from the liquid crystal state to the liquid state; or control the temperature of the viewing angle control unit 220 to be lower than the clearing point of the liquid crystal 221, so that the liquid crystal 221 is converted from the liquid state to the liquid crystal state.

It can be understood that the liquid crystal 221 is composed of a variety of liquid crystal monomers, and the clearing point of the liquid crystal 221 can be freely adjusted by adjusting the liquid crystal monomers, so that the clearing point of the liquid crystal 221 can be adjusted to a suitable value according to the ambient temperature of the application scenario of the display panel.

Optionally, the liquid crystal 221 may be LCCC-18-398, with a clearing point of 79.6°C.

Optionally, the wavelength dispersion of the birefringence of the liquid crystal 221 is positive dispersion, so as to have a greater impact on the second light when the liquid crystal 221 has anisotropy, thereby increasing the light leakage degree of the display panel to the second light.

Since the liquid crystal 221 material itself also has positive dispersion, the phase delay of the light with a longer wavelength in the second light is smaller, and the phase delay of the light with a shorter wavelength is larger. On this basis, the greater the birefringence of the liquid crystal 221, the higher the positive dispersion.

Optionally, the first polarizer 212 reuses the polarizer originally provided in the display panel, so as to reduce the cost while realizing the second display mode, and does not have a significant impact on the thickness of the display panel.

Optionally, please continue to refer to FIG. 2A and FIG. 2B , the viewing angle control unit 220 further includes a first alignment layer 222 and a second alignment layer 223. The first alignment layer 222 is located between the heating resistor and the liquid crystal 221, and the second alignment layer 223 is located between the liquid crystal 221 and the first polarizer 212, so as to achieve the alignment of the liquid crystal 221 (such as achieving the alignment of the liquid crystal 221 in a vertical arrangement).

Optionally, the viewing angle control unit 220 further includes a first electrode layer and a second electrode layer, wherein the first electrode layer is located between the heating resistor and the liquid crystal 221 , and the second electrode layer is located between the liquid crystal 221 and the first polarizer 212 , so as to achieve alignment of the liquid crystal 221 .

Optionally, the first electrode layer is disposed on the entire surface, and the second electrode layer is disposed on the entire surface, so as to achieve the alignment of the liquid crystal 221 at various locations in the viewing angle control unit 220 .

Optionally, when the first electrode layer and the second electrode layer are powered on, the liquid crystal 221 is arranged vertically so that the display panel is in the second display mode; when the first electrode layer and the second electrode layer are not powered on, the heating unit 230 controls the temperature of the viewing angle control unit 220 to be greater than the clearing point of the liquid crystal 221 so that the display panel is in the first display mode.

Optionally, the viewing angle control unit 220 further includes a carrier substrate 224 , and the carrier substrate 224 is located between the second alignment layer 223 and the first polarizer 212 ; or the carrier substrate 224 is located between the second electrode layer and the first polarizer 212 .

The present application also provides a display device, comprising any of the above-mentioned display panels.

Optionally, as shown in Figure 3 which is a structural schematic diagram of the display device provided in an embodiment of the present application, the display device may further include a backlight module 310; wherein the backlight module 310 is located on the side of the color film substrate 211 away from the viewing angle control unit 220, and the backlight module 310 is configured to provide a light source to the display panel so that the display panel can realize a display function.

Optionally, the backlight module 310 is located on a side of the second polarizer 215 away from the viewing angle control unit 220 .

Since the backlight module 310 is located on the side of the second polarizer 215 away from the viewing angle control unit 220, the viewing angle control unit 220 will not affect the light provided by the backlight module 310 to the display control unit 210. Therefore, the display effect generated by the color film substrate 211, the array substrate 213, the display liquid crystal layer 214 and the second polarizer 215 according to the backlight module will not be affected, thereby ensuring that the display panel has a better display source.

Optionally, the display device further includes parts not shown, such as a driving module.

It can be understood that the display device includes a movable display device (such as a laptop computer, a mobile phone, etc.), a fixed terminal (such as a desktop computer, a television, etc.), a measuring device (such as a sports bracelet, a thermometer, etc.), etc.

Specific examples are used herein to illustrate the principles and implementation methods of the present application. The description of the above embodiments is only used to help understand the method and core idea of the present application. At the same time, for technical personnel in this field, according to the idea of the present application, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as a limitation on the present application.

Claims (15)

A display panel, comprising: A display control unit, comprising a color filter substrate and a first polarizer located on the color filter substrate; A viewing angle control unit, located between the color film substrate and the first polarizer, comprising liquid crystal; and A heating unit, configured to control the temperature of the viewing angle control unit to be greater than a clearing point of the liquid crystal in a first display mode; The visible viewing angle of the display panel in the first display mode is greater than the visible viewing angle of the display panel in the second display mode. The display panel according to claim 1, wherein the heating unit comprises: The heating resistor is located between the viewing angle control unit and the color filter substrate. The display panel according to claim 2, wherein the color film substrate comprises: A color filter, comprising a plurality of color filter units and a black matrix located between the plurality of color filter units; Wherein, the orthographic projection of the heating resistor on the color filter coincides with the black matrix. The display panel according to claim 2, wherein the viewing angle control unit further comprises: A first alignment layer, located between the heating resistor and the liquid crystal; and The second alignment layer is located between the liquid crystal and the first polarizer. The display panel according to claim 2, wherein the viewing angle control unit further comprises: A first electrode layer, located between the heating resistor and the liquid crystal; and The second electrode layer is located between the liquid crystal and the first polarizer. The display panel according to claim 1, wherein the wavelength dispersion of the birefringence of the liquid crystal is positive dispersion. The display panel according to claim 1, wherein the clearing point of the liquid crystal is not equal to the ambient temperature of the display panel. The display panel according to claim 7, wherein the clearing point of the liquid crystal is greater than the ambient temperature of the display panel. The display panel according to claim 1, wherein the display control unit further comprises: An array substrate, located at a side of the color filter substrate away from the viewing angle control unit; A second polarizer is located on a side of the array substrate away from the color filter substrate; and The display liquid crystal layer is located between the array substrate and the color film substrate. The display panel according to claim 2, wherein the display control unit further comprises a scan line and a data line; Wherein, the orthographic projection of the heating resistor on the display control unit coincides with at least one of the scanning line and the data line. The display panel according to claim 2, wherein the orthographic projections of the heating resistors on the display control unit are uniformly distributed. The display panel according to claim 2, wherein the orthographic projection of the heating resistors on the display control unit is distributed in a strip matrix. A display device, comprising: The display panel comprises a display control unit, a viewing angle control unit and a heating unit, wherein the display control unit comprises a color film substrate and a first polarizer on the color film substrate, the viewing angle control unit is located between the color film substrate and the first polarizer, the viewing angle control unit comprises liquid crystal, and the heating unit is configured to control the temperature of the viewing angle control unit to be greater than a clearing point of the liquid crystal in a first display mode; and A backlight module is located on a side of the color film substrate away from the viewing angle control unit; The visible viewing angle of the display panel in the first display mode is greater than the visible viewing angle of the display panel in the second display mode. The display device according to claim 13, wherein the heating unit comprises: The heating resistor is located between the viewing angle control unit and the color filter substrate. The display device according to claim 14, wherein the color film substrate comprises: A color filter, comprising a plurality of color filter units and a black matrix located between the plurality of color filter units; Wherein, the orthographic projection of the heating resistor on the color filter coincides with the black matrix.