Display assembly including a first display panel and a second display panel stacked over the first display panel for improving a contrast ratio, and display device

The present application discloses a display assembly and a display device. The display assembly includes a first display panel, a second display panel and a driving circuit; the second display panel is arranged in a stack with the first display panel; the first display panel and the second display panel have the same resolution, and the driving circuit outputs the same data driving signal to the first display panel and the second display panel; light emitting surfaces of the first display panel and the second display panel face the same direction.

The present application claims priority to Chinese Patent Application No. 202010756102.1, filed Jul. 3, 2020 and No. 202021569875.0, filed Jul. 31, 2020, which is hereby incorporated by reference herein as if set forth in its entirety.

TECHNICAL FIELD

The present application relates to the field of display technologies, particularly to a display assembly and a display device.

BACKGROUND

The statements herein merely provide background information related to the present application and do not necessarily constitute the conventional art.

Display devices, such as liquid crystal display devices, have many advantages, for example such as thin body, power saving, and flee of radiation, and have been widely used. Most liquid crystal display devices are backlight type display devices, which include a display assembly (including a display panel and a backlight module). The working principle of the display assembly is to place liquid crystal molecules in two parallel substrates and apply driving voltage on the two substrates to control the rotation direction of the liquid crystal molecules to refract the light of the backlight modules to generate a picture.

However, as people's pursuit of quality becomes higher and higher, the relatively lower display contrast and the like of existing liquid crystal display devices are difficult to meet the pursuit of higher display quality of some people, to improve the display contrast of the liquid crystal display devices remains an urgent problem to be solved by those skilled in the art.

SUMMARY

The purpose of the present application is to provide a display assembly and a display device to improve the contrast of the display device.

The present application discloses a display assembly including, a first display panel, a second display panel and a driving circuit, where the second display panel is arranged in a stack with the first display panel; the driving circuit drives the first display panel and the second display panel to display pictures; the first display panel and the second display panel have the same resolution, and the driving circuit outputs the same data driving signal to the first display panel and the second display panel; light emitting surfaces of the first display panel and the second display panel face the same direction.

The present application further discloses a driving method for the display assembly, the method includes:

receiving an information source signal; and

processing according to the information source signal, and simultaneously outputting a first data driving signal, a second data driving signal and a timing control signal to drive a first display panel and a second display panel;

where the first data driving signal and the second data driving signal are the same, the first data driving, signal is output to the first display panel, the second data driving signal is output to the second display panel, and the timing control signal is simultaneously output to the first display panel and the second display panel.

The present application also discloses a display device including the display assembly disclosed herein.

For the solution that the display assembly only includes a single-layer display panel, the display assembly of the present application includes a first display panel and a second display panel. The dual-layer display panel enables the ratio of the brightness of a point on the screen of the display assembly when the screen is brightest (white) to the brightness of the same point when the screen is darkest (black) to be increased, so that the display contrast is greatly improved; moreover, the first display panel and the second display panel have the same resolution, and the driving circuit outputs the same data driving signal to drive the first display panel and the second display panel to display the picture, so that the two data driving signals do not need to carry out an extra algorithm chip to process the data driving signal and the like to meet the driving of the display panels with different resolutions, in which the driving architecture is simple, and the display contrast is improved while the production cost is favorably reduced.

DETAILED DESCRIPTION OF EMBODIMENTS

It should be understood that the terminology, specific structural and functional details disclosed are merely exemplary for the purpose of describing specific embodiments. However, the present application may be embodied in many alternative forms and should not be construed as being limited to the embodiments set forth herein.

In the description of the present application, the terms “first” and “second” are only for the purpose of description and cannot be construed to indicate relative importance or imply an indication of the number of technical features indicated. Therefore, unless otherwise stated, a feature defined as “first” and “second” may explicitly or implicitly include one or more of the features; “multiple” means two or more. The term “include” and any variations thereof are intended to be inclusive in a non-closed manner, that is, the presence or addition of one or more other features, integers, steps, operations, units, components and/or combinations thereof may be possible.

In addition, the terms “center”, “horizontally”, “up”, “down”, “left”, “right”, “vertical”, “horizontal”, “top”, “bottom”, “inner”, “outer” and the like for indicating an orientation or positional relationship are based on the description of the orientation or relative positional relationship shown in the accompanying drawings, and are only simplified description facilitating description of the application, and are not intended to indicate that the device or element referred to must have a particular orientation, be configured and operated in a particular orientation, and therefore cannot be construed as limiting the present application.

In addition, unless expressly specified and defined otherwise, the terms “mount”, “attach” and “connect” are to be understood broadly, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be an either mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, or an internal connection between two elements. For those skilled in the art, the specific meaning of the above terms in this application can be understood according to the specific circumstances.

FIG. 1is a schematic diagram of an exemplary display assembly according to the present application, referring toFIG. 1, the drawing on the left side in the figure is an overall structure diagram of the display assembly including only a single-layer display panel, and the drawing on the right side in the figure is a corresponding cross-sectional view showing a specific film layer structure of the display assembly including only a single-layer display panel. Specifically, the display assembly200includes an upper polarizer213, an upper substrate250, a liquid crystal layer251, a lower substrate252and a lower polarizer223, where a color filter layer253is correspondingly arranged on the upper substrate250or the lower substrate252, and a backlight module may be arranged on a side of the lower polarizer223away from the upper polarizer213to provide a light source. However, such a structure is inferior to a display panel such as an Organic Light-Emitting Diode (OLED) in characteristics such as a display contrast of the display assembly. Therefore, the applicant improves the display structure of the display assembly to obtain the improved display assembly below.

FIG. 2is a schematic diagram of an improved display assembly according to the present application, referring toFIG. 2, the drawing on the left side in the figure is an overall structure diagram of the display assembly including a dual-layer display panel, and the drawing on the right side in the figure is a corresponding cross-sectional view showing a specific film layer structure of the display assembly including the dual-layer display panel. Specifically, the display assembly includes a first display panel201and a second display panel202arranged in a stack, where the first display panel201and the second display panel202each includes an upper polarizer213, an upper substrate250, a liquid crystal layer251, a lower substrate252, and a lower polarizer223. A backlight module is arranged on a side of the second display panel away from the first display panel, the first display panel has a color filter layer253arranged on the upper substrate250or the lower substrate252, and the second display panel202does not have the color filter layer253, that is, the first display panel201is a color Liquid Crystal Display (LCD), and the second display panel202is a black and white LCD; and the resolution of the first display panel201is greater than that of the second display panel202, specifically, the resolution of the first display panel201is n times that of the second display panel202, with n being greater than or equal to 2. The applicant finds that the display contrast of the improved display assembly is improved, but the color saturation is not obviously improved, and because the resolutions of the two display panels are different, two timing controllers with different resolutions are required, and additional algorithm chips are required for generating data driving information and the like corresponding to the second display panel to realize the display performance of the dual-layer display assembly, so that the driving architecture is complex, and the cost is greatly increased. Based on the above, the applicant has further improved the solution as follows.

The present application will now be described in details by reference to the accompanying drawings and optional embodiments.

FIG. 3is a schematic diagram of a display device according to an embodiment of the present application, and referring toFIG. 1, the present application discloses a display device100including a display assembly200disclosed herein.

The present application discloses the display assembly as follows.

FIG. 4is a schematic diagram of a display assembly according to an embodiment of the disclosure, and referring toFIG. 2, the display assembly200includes a first display panel201, a second display panel202, and a driving circuit203, where the second display panel202is arranged in a stack with the first display panel201. The driving circuit203drives the first display panel201and the second display panel202to display pictures; the first display panel201and the second display panel202have the same resolution, and the driving circuit203outputs the same data driving signal to the first display panel201and the second display panel202; light emitting surfaces of the first display panel201and the second display panel202face the same direction.

For the solution that the display assembly only includes a single-layer display panel, the display assembly200of the present application includes a first display panel201and a second display panel202. The dual-layer display panel enables the ratio of the brightness of a point on the screen of the display assembly when the screen is brightest (white) to the brightness of the same point when the screen is darkest (black) to be increased, so that the display contrast is greatly improved; moreover, the first display panel201and the second display panel202have the same resolution, and the driving circuit203outputs the same data driving signal to drive the first display panel201and the second display panel202to display the picture, so that the two data driving signals do not need to carry out an extra algorithm chip to process the data driving signal and the like to meet the driving of the display panels with different resolutions, in which the driving architecture is simple, and the display contrast is improved while the production cost is favorably reduced.

FIG. 5is a schematic diagram of different source electrode driving circuits driving different display panels according to an embodiment of the present application, and in combination withFIGS. 3 and 4, specifically, the driving circuit203includes: a first source electrode driving circuit205and a second source electrode driving circuit206, where the first source electrode driving circuit205receives a first information source signal and outputs a first data driving signal to drive the first display panel201; the second source electrode driving circuit206receives a second information source signal and outputs a second data driving signal to drive the second display panel202; where the first information source signal and the second information source signal are the same, and the first data driving signal and the second data driving signal are the same. The first information source signal and the second information source signal being the same means that the received information source signals are the same at the same time, and the first data driving signal and the second data driving signal being the same means that the data driving signals output to the two display panels are the same at the same time; the first source electrode driving circuit and the second source electrode driving circuit receive the same information source signal and then output the same data driving signal to drive and display the same picture, so that the display contrast is improved, and meanwhile, the display quality is improved; and because the signal source signal is the same as the data driving signal, an additional algorithm chip or circuit is not needed for processing the signal, the production cost is favorably reduced.

FIG. 6is a schematic diagram of the same source electrode driving circuit driving different display panels according to an embodiment of the present application, and the source electrode driving circuit may also be shared, that is, the driving circuit203includes a source electrode driving circuit204, and the source electrode driving circuit204receives an information source signal and outputs a first data driving signal and a second data driving signal, where the source electrode driving circuit outputs the first data driving signal to the first display panel201and the second data driving signal to the second display panel202; where the first data driving signal and the second data driving signal are the same. The source electrode driving circuit204is shared for driving two display panels, so that the space occupation can be saved and the space utilization rate can be improved.

FIG. 7is a schematic diagram of the same source electrode chip on film driving different display panels according to an embodiment of the present application, and in combination withFIGS. 3 to 6, the solution of the sharing of the source electrode driving circuit can be varied, for example, the source electrode driving circuit204can include at least one source electrode chip on film241with the source electrode driving circuit204arranged thereon; the source electrode chip on film241includes a first output binding pin242and a second output binding pin243, where the first output binding pin242is bound to the first display panel201, and the second output binding pin243is bound to the second display panel202. The source electrode chip on film241is shared, the source electrode chip on film241is provided with a source electrode driving chip, which can also be shared, and then a first output binding pin242and a second output binding pin243from the same source electrode chip on film241are bound and connected to the two display panels respectively. The source electrode driving chip can be two source electrode driving chips or one source electrode driving chip, and when only one source electrode driving chip is arranged on one source electrode chip on film, two groups of identical output binding pins can be provided to ensure the consistency of output data signals.

Another important improvement of the present application is: the display assembly further includes a timing control circuit207that outputs the same timing control signal to the first display panel201and the second display panel202. The consistency of the timing control signals may ensure the consistency of the picture displays of the first display panel and the second display panel, thereby avoiding the problems of disordered picture display and the like while improving the display contrast.

Specifically, the display assembly includes a print circuit board with the timing control circuit207arranged thereon; the source electrode driving circuit includes at least one first source electrode chip on film and at least one second source electrode chip on film, where the first source electrode chip on film is bound to a first surface of the print circuit board close to the first display panel, and the second source electrode chip on film is formed on a second surface of the print circuit board close to the second display panel, where the first surface and the second surface are two surfaces of the print circuit board arranged opposite to each other. The first source electrode chip on film and the second source electrode chip on film are respectively arranged being bound and connected to two surfaces of the print circuit board, which improves the space occupancy rate of the print circuit board, and reduces the length of wiring as much as possible, thus facilitating to reduce the impedance loss while improving space occupancy rate of the print circuit board.

The timing control circuit may include a first interface and a second interface, where the first interface outputs a first timing control signal to the first display panel, and the second interface outputs a second timing control signal to the second display panel. The setting mode of the timing control circuit can be varied, as long as the same timing control signal is output to the first display panel and the second display panel to ensure that the timings are corresponding. Specifically, the timing control circuit may be arranged on the print circuit board, and the print circuit board may be provided with at least one first interface and at least one second interface corresponding to the timing control circuit, and configured to be bound and connected to the first display panel and the second display panel through the source electrode chip on film (the source electrode chip on film may also be directly or indirectly connected to the two display panels through the adaptive connector) respectively, to implement the use of the print circuit board and the timing control circuit together.

FIG. 8is a schematic circuit block diagram of a display assembly according to an embodiment of the present application, and in combination withFIGS. 3 to 7, the present application also improves other circuits of the display assembly, specifically, the display assembly further includes a gamma voltage generation circuit230, a common voltage generation circuit231, and a power supply conversion circuit232, where the gamma voltage generation circuit230outputs the same gamma voltage to the first display panel201and the second display panel202; the common voltage generation circuit231outputs the same common voltage to the first display panel201and the second display panel202; the power supply conversion circuit232outputs the same data power supply voltage to the source electrode driving circuits204corresponding to the first display panel201and the second display panel202, and outputs the same gate electrode power supply voltage to the gate electrode driving circuits233corresponding to the first display panel201and the second display panel202; specifically, the power supply conversion circuit and the common voltage circuit may be connected to the source electrode driving circuits in the first display panel and the second display panel, and then transmit the power supply voltage and the like required by the gate electrode driving circuit and the like through an additional wiring or an idle pin on the source electrode chip on film where the source electrode driving circuit is located, or transmit the common voltage to the common line of the corresponding display panel. In addition, the display assembly further includes an input connector235, a memory234and the like, where the input connector235is configured for transmitting an externally transmitted information source signal to the timing control circuit207and the like, and the memory234is configured for being connected to the timing control circuit207, the gamma voltage generation circuit, the common voltage generation circuit and the like to help generate an adaptive timing control signal, gamma voltage, common voltage and the like; where the gamma voltage generation circuit and the common voltage generation circuit can be integrated into a gamma voltage and common voltage generator; therefore various circuits can be used with their corresponding electronic components, such that the number of the independent electronic components is far lower than that of the two display panels working independently, which reduces the space occupation as well as the cost; where the power supply conversion circuit more specifically includes a direct current to direct current conversion circuit.

FIG. 9is a schematic diagram of a film layer structure of a display assembly according to an embodiment of the present application, and in combination withFIGS. 3 to 8, the drawing on the left side in the figure is an overall structure diagram of the display assembly including a dual-layer display panel, and the drawing on the right side in the figure is a corresponding cross-sectional view showing a specific film layer structure of the display assembly including a dual-layer display panel. Specifically, in addition to improving the circuits, the film layer structure of the display assembly is also improved, in the present application, the first display panel201and the second display panel202are fixed by binding with an Optical Clear Adhesive (OCA)254; the first display panel201sequentially includes, from top to bottom, a first substrate210, a second substrate212, and a first liquid crystal layer211arranged between the first substrate210and the second substrate212; the second display panel202sequentially includes, from top to bottom, a third substrate220, a fourth substrate222, and a second liquid crystal layer221arranged between the third substrate220and the fourth substrate222; where the thicknesses of the first liquid crystal layer211and the second liquid crystal layer221are the same. That is, the first liquid crystal layer and the second liquid crystal layer have the same thickness on the basis of the same other conditions (e.g., materials, etc.), so that the first liquid crystal layer and the second liquid crystal layer have the same transmittance. The OCA254is disposed between the second substrate212and the third substrate220to bind and fix the second substrate212and the third substrate220.

Specifically, the first color filter layer includes a plurality of first red resists, a plurality of first green resists, and a plurality of first blue resists, the second color filter layer includes a plurality of second red resists, a plurality of second green resists, and a plurality of second blue resists, where the plurality of first red resists and the plurality of second red resists have the same thickness and are arranged correspondingly in the direction perpendicular to the light-emitting surface of the first display panel; the plurality of first green resists and the plurality of second green resists have the same thickness and are arranged correspondingly in the direction perpendicular to the light-emitting surface of the first display panel; the plurality of first blue resists and the plurality of second blue resists have the same thickness and are arranged correspondingly in the direction perpendicular to the light emitting surface of the first display panel. That is, the first color filter layer and the second color filter layer have the same thickness and are arranged correspondingly on the basis of the same other conditions (including materials and the like). The color resist included in the first color filter layer and the second color filter layer of the present application may be red green blue (RGB) resist, red green blue white (RGBW) resist, red green blue yellow (RGBY) resist, and resists of other colors, as long as they are applicable.

The display assembly further includes an upper polarizer213, a lower polarizer223and a middle polarizer224, the upper polarizer213is arranged on the first display panel201, the lower polarizer223is arranged on the second display panel202, and the middle polarizer224is arranged between the upper polarizer213and the lower polarizer223. The upper polarizer213and the lower polarizer223have the same polarization direction, and the middle polarizer224is perpendicular to the polarization direction of the upper polarizer213and the lower polarizer223. The upper polarizer213may be arranged on the first substrate210, the lower polarizer223may be arranged on the fourth substrate222, and the middle polarizer224may be arranged on the second substrate212or the third substrate220, and more specifically, may be arranged on a side of the second substrate212close to the third substrate220or a side of the third substrate220close to the second substrate212. The arrangement of three polarizers with the middle one being shared reduces the number of the polarizers being used, and the reasonable cooperation of the three polarizers is favorable for improving the contrast and the color saturation.

Referring toFIGS. 3 to 9, the present application further discloses a display assembly200including a first display panel201, a second display panel202, a backlight module240, a source electrode chip on film241, and a timing control circuit207, where the second display panel202is arranged in a stack with the first display panel201, and the first display panel201and the second display panel202have the same resolution. The second display panel202is arranged between the first display panel201and the backlight module240, a plurality of source electrode chip on films241are provided, each of which includes a first output binding pin242and a second output binding pin243, the first output binding pin242is bound to the first display panel201, and the second output binding pin243is bound to the second display panel202; the first and second output binding pins242and243output the same data driving signal to the first and second display panels201and202. The timing control circuit207is configured to output the same timing control signal to the first display panel201and the second display panel202. The display assembly200further includes a first color filter layer208and a second color filter layer209, where the first color filter layer208is correspondingly arranged on the first display panel201, and the second color filter layer209is correspondingly arranged on the second display panel202; where the first color filter layer208and the second color filter layer209each includes a plurality of color resists for different colors, and the color resists for the same color in the first color filter layer208and the second color filter layer209are arranged correspondingly in the direction perpendicular to the light emitting surface of the first display panel201. This solution can not only improve the display contrast and color saturation, but also realize the sharing of the backlight module, which saves space occupation and reduces power consumption.

FIG. 10is a flowchart of a driving method for a display assembly according to an embodiment of the present application, and in combination withFIGS. 3 to 9, the present application further discloses a driving method for a display assembly, including:

S1: receiving an information source signal;

S2: processing according to the information source signal, and simultaneously outputting a first data driving signal, a second data driving signal and a timing control signal to drive a first display panel and a second display panel;

where the first data driving signal and the second data driving signal are the same, the first data driving signal is output to the first display panel, the second data driving signal is output to the second display panel, and the timing control signal is simultaneously output to the first display panel and the second display panel.

It should be noted that, the limitation of the steps involved in this solution, without affecting the implementation of the specific solution, is not determined to limit the sequence of steps, and the previous steps may be executed first, later, or even simultaneously; similarly, various related technical features in this solution can be combined without conflict. As long as the solution can be implemented, the technical features shall fall within the protection scope of the present application.

The technical solution of the present application can be applied to a wide variety of display assemblies, such as Twisted Nematic (TN) display assemblies, In-Plane Switching (IPS) display assemblies, Vertical Alignment (VA) display assemblies, Multi-domain Vertical Alignment (MVA) display assemblies, and other types of display assemblies.

The above content is a further detailed description of the present application in conjunction with specific, optional embodiments, and it is not to be construed that specific embodiments of the present application are limited to these descriptions. For those of ordinary skill in the art to which this application belongs, a number of simple derivations of substitutions may be made without departing from the spirit of this application, all of which shall be deemed to fall within the scope of this application.