Display panel and display device

Abstract

The invention provides a display module and a display device, the display module comprises a display panel and an optical modulation element, and the display panel comprises a pixel area and a non-pixel area; the optical modulation element is at least located in the non-pixel area; the working process of the display panel comprises at least one light-emitting stage and at least one non-light-emitting stage. The working state of the optical modulation element comprises a first state and a second state; the light transmittance of the optical modulation element in the first state is greater than that of the optical modulation element in the second state; in the light emitting stage, the optical modulation element is in the second state. In the light emitting stage of the display module, the light transmitting state of the optical modulation element is switched into the second state with the low light transmittance, so that stray light of a large viewing angle in the display module is prevented from penetrating through the back face of the display module, light leakage of the backlight face of the display module is reduced, the problem that back face content is visible is solved, meanwhile, the part of light can be absorbed, and the display effect is improved. The halo phenomenon is improved, and the display effect is improved.

Description

Technical Field

[0001] Embodiments of the present invention relate to the field of display technology, and in particular to a display panel and a display device. Background Art

[0002] At present, transparent displays can bring users a unique visual experience because the screen content can be integrated with the background when displaying. Compared with traditional displays, they are thinner and save more space. For example, they can be used for product display, and customers can see the product and the screen information at the same time, attracting more attention in places such as shopping malls and airports.

[0003] However, when transparent displays are used, the content displayed on the back of the screen may be visible, which may easily leak personal privacy in some applications. Therefore, its display performance needs to be improved. Summary of the invention

[0004] The present invention provides a display module and a display device. An optical modulation element is set. In the light-emitting stage, the light transmittance state of the optical modulation element is switched to a second state with lower light transmittance, so as to block the stray light with a large viewing angle in the display module from passing through the back of the display module, reduce the light leakage of the backlight surface of the display module, improve the problem of the visibility of the back content, and absorb part of the light, improve the halo phenomenon, and enhance the display effect.

[0005] In a first aspect, an embodiment of the present invention provides a display module, including:

[0006] A display panel including a pixel area and a non-pixel area;

[0007] An optical modulation element, at least located in the non-pixel area;

[0008] The working process of the display panel includes at least one light-emitting stage and at least one non-light-emitting stage; the working state of the optical modulation element includes a first state and a second state; the transmittance of the optical modulation element in the first state is greater than the transmittance of the optical modulation element in the second state;

[0009] During the light emitting phase, the optical modulation element is in a second state.

[0010] In a second aspect, an embodiment of the present invention further provides a display device, comprising the display module provided in the first aspect.

[0011] The display module provided by the embodiment of the present invention includes a display panel and an optical modulation element, the display panel includes a pixel area and a non-pixel area; the optical modulation element is at least located in the non-pixel area; the working process of the display panel includes at least one light-emitting stage and at least one non-light-emitting stage; the working state of the optical modulation element includes a first state and a second state; the transmittance of the optical modulation element in the first state is greater than the transmittance of the optical modulation element in the second state; in the light-emitting stage, the optical modulation element is in the second state. Adopting the above technical scheme, the embodiment of the present invention sets an optical modulation element, the optical modulation element includes at least two first states and second states with different transmittances, and in the light-emitting stage of the display module, the transmittance state of the optical modulation element is switched to the second state with lower transmittance, so as to block the stray light with a large viewing angle in the display module from passing through the back of the display module, reduce the light leakage of the backlight surface of the display module, improve the problem of the visibility of the back content, and absorb this part of the light, improve the halo phenomenon, and improve the display effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 It is a cross-sectional schematic diagram of a transparent display screen provided by the prior art;

[0013] Figure 2 yes Figure 1 A schematic diagram of a transparent display screen providing a transparent display effect;

[0014] Figure 3 is a structural schematic diagram of a display module provided by an embodiment of the present invention;

[0015] Figure 4 yes Figure 3 A schematic cross-sectional view of a display module provided along the AA' direction;

[0016] Figure 5 yes Figure 3 A schematic cross-sectional view of another display module provided along the AA' direction;

[0017] Figure 6 yes Figure 4 A schematic diagram of display effect of a display module is provided;

[0018] Figure 7 is a circuit structure schematic diagram of a pixel circuit provided by an embodiment of the present invention;

[0019] Figure 8 yes Figure 7 A timing diagram of a scanning signal and a light emitting control signal in a pixel circuit is provided;

[0020] Fig. 9 yes Figure 3 A schematic cross-sectional view of another display module provided along the AA' direction;

[0021] Fig.10 yes Figure 3 A schematic cross-sectional view of another display module provided along the AA' direction;

[0022] Fig.11 The present invention provides a timing diagram of a light emitting control signal and a modulation control signal;

[0023] Fig.12 It is another timing diagram of a light emitting control signal and a modulation control signal provided by the present invention;

[0024] Fig.13 yes Figure 4 A schematic diagram of display effect of another display module provided;

[0025] Fig.14 is a schematic structural diagram of an optical modulation element provided by the present invention;

[0026] Fig.15 is a schematic structural diagram of another optical modulation element provided by the present invention;

[0027] Fig.16 is a schematic structural diagram of another optical modulation element provided by the present invention;

[0028] Fig.17 It is a structural schematic diagram of a display device provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0029] The present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments. It is to be understood that the specific embodiments described herein are only used to explain the present invention, rather than to limit the present invention. It should also be noted that, for ease of description, only parts related to the present invention, rather than all structures, are shown in the accompanying drawings.

[0030] Figure 1 is a cross-sectional schematic diagram of a transparent display screen provided by the prior art. Figure 2 yes Figure 1 A transparent display screen transparent display effect diagram provided, reference Figure 1 and Figure 2, taking the Micro LED (Micro Light Emitting Diode Display, Micro LED) transparent display screen 100 in the prior art as an example, at present, the light-emitting chip (Micro LED) used in the Micro LED display screen 100 is relatively small in size, and the pixel area ratio is relatively low compared to that of OLED (Organic Light Emitting Diode, OLED), which makes it have higher transparency and has good application prospects in the field of transparent display. However, usually the transparent display screen 100 has a transparent area. When transparent display is performed, the external light S0 will be seen by user A through the transparent area, and part of the light S emitted from the front of the Micro LED will be emitted from the light-emitting surface of the transparent display screen 100 and seen by user A. However, due to the existence of the transparent area, there is also part of the large-angle light S emitted from the front of the Micro LED, which will be reflected and / or totally reflected at the interface of each film layer inside the display screen, and then become stray light. This part of the stray light leaks from the side and back of the display screen through the transparent area, and is seen by user B, making the back content visible. In some privacy displays, it is easy to leak personal privacy. At the same time, this part of the light leakage will also cause the display screen to have a halo phenomenon, affecting the display effect.

[0031] Transparent display means that when the display screen displays an image, the surrounding image on the back of the display screen can be seen at the same time. The main reason for the halo of transparent display screens is that part of the light emitted by the light-emitting element is totally reflected during the horizontal propagation in the display screen, and this part of the light encounters the light diffuse reflection of non-transparent materials during the horizontal propagation.

[0032] Based on this, an embodiment of the present invention provides a display module, which includes a display panel and an optical modulation element, the display panel includes a pixel area and a non-pixel area; the optical modulation element is at least located in the non-pixel area; the working process of the display panel includes at least one light-emitting stage and at least one non-light-emitting stage; the working state of the optical modulation element includes a first state and a second state; the transmittance of the optical modulation element in the first state is greater than the transmittance of the optical modulation element in the second state; in the light-emitting stage, the optical modulation element is in the second state.

[0033] By adopting the above technical solution, an embodiment of the present invention sets an optical modulation element in at least a non-pixel area of ​​the display module, and the optical modulation element includes at least two first states and a second state with different transmittances. When the display module is in the light-emitting stage, the transmittance state of the optical modulation element is switched to the second state with lower transmittance, so as to block the stray light with a large viewing angle in the display module from passing through the back of the display module, reduce the light leakage on the backlight surface of the display module, improve the problem of visibility of the back content, and at the same time absorb this part of the light, improve the halo phenomenon, and enhance the display effect.

[0034] The above is the core idea of ​​the present invention. The technical scheme in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0035] Figure 3 is a structural schematic diagram of a display module provided by an embodiment of the present invention; Figure 4 yes Figure 3 A schematic cross-sectional view of a display module provided along the AA' direction, Figure 5 yes Figure 3 A schematic cross-sectional view of a display module provided along the AA' direction, Figure 6 yes Figure 4 A schematic diagram of a display effect of a display module is provided. Figure 7 is a schematic diagram of a circuit structure of a pixel circuit provided by an embodiment of the present invention, Figure 8 yes Figure 7 The timing diagram of the scanning signal and the light-emitting control signal in the pixel circuit provided is shown in Fig. Figure 3-Figure 5 A display module 300 provided in an embodiment of the present invention includes a display panel 200 and an optical modulation element 10, and the display panel 200 includes a pixel area 01 and a non-pixel area 02. The optical modulation element 10 is at least located in the non-pixel area 02, and the working process of the display panel 200 includes at least one light-emitting stage and at least one non-light-emitting stage. The working state of the optical modulation element 10 includes a first state and a second state. The transmittance of the optical modulation element 10 in the first state is greater than the transmittance of the optical modulation element 10 in the second state. When the display panel 200 is in the light-emitting stage, the optical modulation element 10 is in the second state. Among them, the second state can also be called a privacy state.

[0036] refer to Figure 3 In an embodiment of the present invention, the display panel 200 may be an organic light emitting display panel (OLED), a micro light emitting diode display panel (Micro LED), a light emitting diode display panel (Light Emitting Diode Display, Micro LED), etc., and the embodiment of the present invention does not limit this.

[0037] refer to Figure 3-Figure 5, a plurality of light-emitting elements 011 are arranged in the pixel area 01, such as a red light-emitting element R, a green light-emitting element G, and a blue light-emitting element B. No light-emitting element 011 is arranged in the non-pixel area 02. The type of the light-emitting element 011 may be OLED, Micro LED, LED, etc., which is not limited in the embodiment of the present invention. In the embodiment of the present invention, the display panel 200 may be a transparent display panel, and each film layer structure is formed by a transparent material. It should be noted that the pixel area 01 may also be understood as an area where the sub-pixel 011 is arranged, and the non-pixel area 02 may be understood as an area where the sub-pixel 011 is not arranged.

[0038] Need to explain, Figure 4 This is just an example of the pixel area 01 and the non-pixel area 02. The pixel area 01 and the non-pixel area 02 may be regular areas or irregular areas. The embodiment of the present invention does not limit the position, size, etc. of the pixel area 01 and the non-pixel area 02.

[0039] The light-emitting stage refers to the light-emitting element 011 emitting light to display an image, and the non-light-emitting stage refers to the light-emitting element 011 not emitting light. In the light-emitting stage, the pixel area 01 of the display panel 200 emits light, and the non-pixel area 02 does not emit light. In the non-light-emitting stage, both the pixel area 01 and the non-pixel area 02 of the display panel 200 do not emit light.

[0040] refer to Figure 4 and Figure 5 Taking the Micro LED display panel 200 as an example, the display panel 200 generally includes a base substrate 20, a driving circuit layer 30 and a plurality of light-emitting elements 011 located on one side of the base substrate 20. The material of the base substrate 20 includes but is not limited to rigid materials such as glass or silicon wafers, and can also be flexible materials such as ultra-thin glass, metal foil or polymer plastic materials. The flexible or rigid base substrate 20 can block oxygen and moisture, and prevent moisture or impurities from diffusing into the display panel 200 through the base substrate 20.

[0041] The driving circuit layer 30 includes a plurality of pixel circuits ( Figure 4 and Figure 5 The pixel circuit is electrically connected to the light emitting element 011 in the pixel area 01, and is used to drive a voltage to the light emitting element 011 to drive the light emitting element 011 to emit light. The pixel circuit can be a circuit structure of 2T1C, 4T1C, 7T1C, 7T2C, 8T1C, 8T2C, etc. The pixel circuit includes a plurality of thin film transistors (TFT), storage capacitors and metal wiring and other film layer structures ( Figure 4 and Figure 5 ). Figure 7, the pixel circuit 301 includes seven thin film transistors and one storage capacitor, that is, a 7T1C circuit, as an example for description. Figure 7 and Figure 8 As shown, the working process of any pixel circuit is briefly described below:

[0042] The first scanning signal line Scan1 controls the on or off of the reset transistor T5 of the pixel circuit, and resets the gate potential of the driving transistor T3 when the reset transistor T5 is on. The second scanning signal line Scan2 controls the on and off of the data writing transistor T2 and the threshold compensation transistor T4 of the pixel circuit, and when the data writing transistor T2 and the threshold compensation transistor T4 are on, the data signal on the data signal line Vdata is written to the gate of the driving transistor T1, and the threshold voltage of the driving transistor T3 is compensated. In some optional pixel circuit designs, the scanning signal Scan n can also be multiplexed to control the on or off of the initialization transistor T7 of the pixel circuit, and when the initialization transistor T7 is on, the anode potential of the light-emitting element 011 is reset. At this time, there is no need to set a scanning signal line separately for the initialization transistor T7.

[0043] In other words, the first scanning signal line Scan1 can be understood as a scanning signal line connected to the control end of the reset transistor T5 in the pixel circuit 301, and the second scanning signal line Scan2 can be understood as a scanning signal line connected to the control end of the data writing transistor T2, the control end of the compensation transistor T4, and the control end of the initialization transistor T7 in the pixel circuit 301. Generally speaking, each row of pixel circuits 301 used for display is at least correspondingly connected to the first scanning signal line Scan1 and the second scanning signal line Scan2.

[0044] The power supply voltage signal line PVDD is used to provide a power supply voltage to the driving transistor T3, and the voltage on the power supply voltage signal line PVDD can be a positive voltage. The voltage on the common power supply signal terminal PVEE can be a negative voltage. The initialization signal line Vref is used to provide a reset voltage signal, and the voltage on the initialization signal line Vref can be a negative voltage.

[0045] It should be noted that the reference Figure 7 The above embodiment is described by taking the case where all transistors in the pixel circuit 301 are P-type transistors as an example. In other optional embodiments, all transistors in the pixel circuit 301 may be N-type transistors, or some may be P-type transistors and some may be N-type transistors. Different enable levels may be provided according to different types of transistors, and the enable level is a level that enables the transistor to be turned on. For example, for an N-type transistor, the enable level is a high level, and for a P-type transistor, the enable level is a low level.

[0046] Among them, in order to meet the driving requirements of the high-resolution display panel, the embodiment of the present invention can use pulse amplitude modulation (Pulse Amplitude Modulation, PAM) to control the driving current intensity, pulse width modulation (Pulse Width Modulation, PWM) to control the duration of the driving current, and adopt a pixel circuit combining PAM and PWM, and a hybrid driving method to control the driving current intensity and the duration of the driving current to control the light-emitting state of the light-emitting element 011 of the pixel area 01.

[0047] Specific, combined Figure 4 , Figure 5 , Figure 7 and Figure 8 As shown, the driving process of the pixel circuit 301 may include an initialization phase, a data writing phase, and a light emitting phase. In the initialization phase, the first scanning signal line Scan1 provides a low-level signal, the reset transistor T5 is turned on, and the gate potential of the driving transistor T3 is reset. In the data writing phase, the second scanning signal line Scan2 provides a low-level signal, the data writing transistor T2 and the threshold compensation transistor T4 are turned on, the data signal on the data signal line Vdata is written to the gate of the driving transistor T1, and the threshold voltage of the driving transistor T3 is compensated; and the initialization transistor T7 is turned on to reset the anode potential of the light emitting element 011. In the light emitting phase, the light emitting control signal line Emit provides a low-level signal, the light emitting control transistor T1 and the light emitting control transistor T6 are turned on, the driving current generated by the driving transistor T3 is transmitted to the light emitting element 011, the light emitting element 011 emits light, and the display panel 200 operates in the light emitting phase.

[0048] In the non-luminous phase, the luminous control signal line Emit outputs an invalid pulse to control the luminous control transistor T1 and the luminous control transistor T6 to be in the off state, so that the luminous element 011 does not emit light, and the display panel 200 operates in the non-luminous phase. It should be noted that, Figure 7 and Figure 8 This is only an example and is not intended to limit the present application.

[0049] It should be noted that the display panel 200 may include at least one light-emitting phase and one non-light-emitting phase within one frame time, and continuously works to form a display image, which will not be elaborated here.

[0050] Furthermore, considering that the non-pixel region 02 does not have a light emitting element 011 and the light transmittance of the film layer in the non-pixel region 02 is relatively high, the backlight surface of the display panel 200 will have light leakage and halo problems when the display panel 200 is working in the light emitting stage. Figure 4 and Figure 5 In the embodiment of the present invention, the optical modulation element 10 is at least arranged in the non-pixel area 02 .

[0051] The optical modulation element 10 is an optical device with adjustable transmittance, for example, an optical film layer containing liquid crystal molecules, etc., and the transmittance of the optical film layer to light is adjusted by changing the rotation angle of the liquid crystal molecules in the optical film layer. When the display panel 200 is working in the light-emitting stage or the non-light-emitting stage, the optical modulation element 10 is controlled to switch between the first state and the second state with different transmittances to improve the different display effects of the display panel 200 in the light-emitting stage and the non-light-emitting stage.

[0052] Specifically, refer to Figure 4 When the optical modulation element 10 switches to the first state with a higher transmittance, the background light S0 and the wide viewing angle display light S' that reaches the non-pixel area 02 after being reflected and / or totally reflected in the display panel 200 can be transmitted. This part of the wide viewing angle display light S' is emitted by the light emitting element 011. Figure 5 When the optical modulation element 10 switches to the second state with lower transmittance, the optical modulation element 10 can block the part of the wide-viewing angle display light S' from passing through the back of the display module 300, thereby avoiding light leakage from the back of the display module 300, and at the same time absorb the part of the wide-viewing angle display light S', thereby improving the halo problem of the display module 300 and improving the display effect.

[0053] Accordingly, reference Figure 5 and Figure 6 In the embodiment of the present invention, when the display panel 200 is in the light-emitting stage, the optical modulation element 10 is switched to the second state with lower transmittance. In this state, the optical modulation element 10 can block and absorb the wide-angle display light S' after reflection and / or total reflection at the interface of each film layer in the display panel 200, and reduce the transmission of this part of the wide-angle display light S' through the back of the display module 300. In the second state, when the display panel 200 is in the light-emitting stage, user A can see the display image on the light-emitting surface (front) of the display module 300, while user B cannot or can only vaguely see the display image on the light-emitting surface of the display module 300, thus improving the problem of light leakage from the back of the display module 300. In particular, in some applications that require privacy protection, it can effectively avoid the leakage of personal privacy caused by light leakage from the back of the display module. Furthermore, since the optical modulation element 10 can also absorb this part of the wide-angle display light S', the halo phenomenon caused by the total reflection of this part of the wide-angle display light S' in the display panel 200 is improved, thereby improving the visual effect of user A.

[0054] It should be noted that the reference Figure 4 and Figure 5, the embodiment of the present invention also includes other film layers, such as black matrix (BlackMatrix, BM), encapsulation layer 50, cover glass (Cover Glass), etc., which work together to realize the display of the display panel, and the embodiment of the present invention will not be repeated. Among them, the encapsulation layer 50 can be a thin film encapsulation layer (Thin-Film Encapsulation, TFE), which can include but is not limited to a first optically transparent layer (Optical Clear, OC) OC1, a second optically transparent layer OC2 and an organic layer OCA, which is used to isolate water and oxygen to prevent external moisture and oxygen from affecting the light-emitting element 011 material. Among them, OCA is an optically clear adhesive (Optically Clear Adhesive, OCA).

[0055] In summary, the embodiments of the invention arrange an optical modulation element in at least a non-pixel area of ​​the display module, and the optical modulation element includes at least two first states and a second state with different transmittances. When the display module is in the light-emitting stage, the transmittance state of the optical modulation element is switched to the second state with lower transmittance, so as to block the stray light with a large viewing angle in the display module from passing through the back of the display module, reduce the light leakage on the backlight surface of the display module, improve the problem of visibility of the back content, and at the same time absorb this part of the light, improve the halo phenomenon, and enhance the display effect.

[0056] Based on the above embodiments, continue to refer to Figure 4 and Figure 5 , the first state of the optical modulation element 10 is a transparent state, and the second state is a non-transparent state. In the embodiment of the present invention, an optical modulation element 10 with a larger light transmittance adjustment range can also be selected, so that the optical modulation element 10 can be switched between transparent and non-transparent states. When the display panel 200 is working in the light-emitting stage, the state of the optical modulation element 10 is controlled to be a non-transparent state to block and absorb the large-viewing angle display light inside the display panel 200, improve the light leakage and halo problems on the back of the display module, and thus improve the transparent display effect of the display module.

[0057] Among them, combined Figure 6 As shown in Table 1, the transparent display of the display module means that when the display module 300 is working in the light-emitting stage, user A can see the display image and the scene behind the display module, and user B cannot see the display image but can see the scene in front of the display module. At this time, the display effect of the display module 300 is to display content privacy.

[0058] On the basis of the above embodiment, when the display panel 200 is in the non-light-emitting stage, the optical modulation element 10 can be in the first state or the second state. In the embodiment of the present invention, when the display panel 200 is in the non-light-emitting stage, the light-emitting element 011 does not emit light, so there is no problem of leakage of the display information of the display panel 200 at this time. Therefore, the optical modulation element 10 can be switched between the first state and the second state according to the needs of the application scenario of the display panel 200.

[0059] Based on the above embodiments, continue to refer to Figure 4 and Figure 5 , the optical modulation element 10 is located on the backlight side of the display module 300. The backlight side is opposite to the light emitting surface of the display module 300. In the embodiment of the present invention, the optical modulation element 10 can be directly attached to the backlight side of the display module 300, and the orthographic projection of the optical modulation element 10 on the display panel 200 at least covers the non-pixel area 02. When the optical modulation element 10 is in the second state, it can block the large-viewing angle display light from passing through the back of the display module 300 to avoid light leakage from the backlight side of the display module 300; at the same time, it can absorb the display light totally reflected in the display panel 200, reduce the appearance of halo, and improve the display effect.

[0060] Based on the above embodiments, continue to refer to Figure 4 and Figure 5 , the optical modulation element 10 is also located in the pixel area 01. In the embodiment of the present invention, the optical modulation element 10 can also completely cover the pixel area 01 and the non-pixel area 02 of the display module 300, referring to Figure 5 When the optical modulation element 10 is in the second state, it blocks and absorbs the wide-viewing angle display light S' reflected and / or totally reflected from each film layer in the pixel area 01 and the non-pixel area 02, thereby preventing this part of the wide-viewing angle light S' from passing through the back of the display module 300, improving the light leakage problem on the backlight side of the display module 300, and reducing the halo.

[0061] Fig. 9 yes Figure 3 A schematic cross-sectional view of another display module provided along the AA' direction, referring to Fig. 9On the basis of the above embodiment, the optical modulation element 10 includes a modulation area 11 and a shielding area 12; the modulation area 11 is located in the non-pixel area 01, the shielding area 12 is located in the pixel area 01, and the modulation area 11 includes a first state and a second state. In the embodiment of the present invention, the optical modulation element 10 can also be divided into zones by a "patterned" structure. The shielding area 12 is set in the pixel area 01, and its transmittance is not adjustable, usually in a non-transparent state. The shielding area 12 can block the light from passing through in the light-emitting stage and the non-light-emitting stage of the display panel 200. The modulation area 11 is set in the non-pixel area 02, and its transmittance can be switched between the first state and the second state. In the light-emitting stage of the display panel 200, the modulation area 11 is switched to the second state with lower transmittance to block and absorb the large-viewing angle display light reflected and / or fully reflected from each film layer of the pixel area 01 and the non-pixel area 02, so as to avoid light leakage from the backlight side of the display module 300. In the non-light-emitting stage of the display panel 200, the modulation area 11 can be in the first state or the second state, which is not limited by the embodiment of the present invention.

[0062] Based on the above embodiments, Fig.10 yes Figure 3 A schematic cross-sectional view of another display module provided along the AA' direction, referring to Fig.10 The optical modulation element 10 can also be arranged in a "patterned" structure inside the film layer of the display panel 200. The display module 300 also includes a base substrate 20 and a driving circuit layer 30, a plurality of light-emitting elements 011 and a planarization layer (PLN) sequentially located on one side of the base substrate 20. In the embodiment of the present invention, the optical modulation element 10 is located between the driving circuit layer 30 and the planarization layer 40 in the non-pixel area 02.

[0063] refer to Fig.10 In the light-emitting stage of the display panel 200, the optical modulation element 10 is in the second state with lower transmittance, such as the non-transparent state, which can block and absorb the wide-angle display light S' emitted by the light-emitting element 011, and prevent this part of the wide-angle display light S' from passing through the back of the display module 300. In the non-light-emitting stage of the display panel 200, the optical modulation element 10 can be in the first state or the second state, which is not limited in the embodiment of the present invention.

[0064] The “patterning” in this article specifically refers to a non-whole-layer structure, that is, a structure in which a whole layer of material is first formed during the manufacturing process and then a specific shape is carved out.

[0065] It should be noted that, continue to refer to Figure 4 , Figure 5 , Fig. 9 and Fig.10, the non-pixel region 02 includes multiple transparent film layers, and the transmittance of the optical modulation element 10 in the first state is greater than or equal to the transmittance of the multiple transparent film layers. The first state can be a transparent state, and each film layer of the display panel 200 of the embodiment of the present invention can be a combination of transparent materials and transparent conductive materials, and each film layer of the non-pixel region 012 and the pixel region 01 is designed as a transparent film layer, which is conducive to improving the transparent display effect of the display module 300.

[0066] Among them, transparent materials include but are not limited to PET (polyethylene terephthalate), PMMA (polymethyl methacrylate), PC (polycarbonate), COP (cycloolefin polymer), PEN (polyethylene naphthalate), SiO2 (silicon dioxide), Si3N4 (silicon nitride), Al2O3 (aluminum oxide), MgF2 (magnesium fluoride), epoxy resin, UV curing glue, OCA (optical clear glue), etc. Transparent conductive materials include but are not limited to ITO (indium tin oxide), GZO (gallium-doped zinc oxide), IZO (indium-doped zinc oxide), silver nanowires, metal mesh, graphene, etc. ZO (gallium-doped zinc oxide), IZO (indium-doped zinc oxide), silver nanowires, metal mesh, graphene, etc.

[0067] Based on the above embodiments, Figure 3-Figure 10 , the optical modulation frequency of the optical modulation element 10 switching between the first state and the second state is the same as the refresh frequency of switching between the light-emitting stage and the non-light-emitting stage. In the embodiment of the present invention, an optical modulation element 10 can be additionally provided on the backlight side of the display panel 200 or inside the film layer, and the optical modulation element 10 has at least two optical modulation states with different light transmittances, such as a transparent state and a non-transparent state, and the two modulation states can be electrically switched.

[0068] The refresh rate of the display panel refers to the number of times the screen updates the image per second, usually in Hertz (Hz). It should be noted that in the embodiment of the present invention, the optical modulation frequency of the optical modulation element 10 refers to the number of times it switches between two modulation states per second. The refresh rate of the display panel 200 switching between the light-emitting stage and the non-light-emitting stage refers to the number of times the light-emitting element 011 switches between the light-emitting stage and the non-light-emitting stage per second. Figure 7 and Figure 8 The refresh frequency of the display panel 200 switching between the light-emitting stage and the non-light-emitting stage can also be understood as the number of times per second that the light-emitting element 011 emits light during the driving process of the pixel circuit 301, the light-emitting control signal line Emit outputs a valid pulse to control the light-emitting control transistor T1 and the light-emitting control transistor T6 to be in the on state.

[0069] Taking the case where the first state is transparent and the second state is non-transparent as an example, the embodiment of the present invention combines PAM and PWM dimming technologies to switch the optical modulation element 10 to a non-transparent state during the light-emitting stage of the light-emitting element 011, so that the display light S emitted by the light-emitting element 011 can only be emitted from the front of the display panel 200; in the non-light-emitting stage of the light-emitting element 011 (after being extinguished), the optical modulation element 10 is switched to a non-transparent state or a transparent state.

[0070] Fig.11 The present invention provides a timing diagram of a light emitting control signal and a modulation control signal. Based on the above embodiment, reference is made to Fig.11 , Emit1 is recorded as the light-emitting control signal of the light-emitting element 011, high level is light-emitting, low level is no light-emitting; Emit2 is recorded as the modulation control signal of the optical modulation element 10 in the second state, high level is the first state, low level is the second state. The time length of a light-emitting stage is T1, and the time length of the optical modulation element 10 in the second state is T2; wherein T1<T2.

[0071] For example, in combination Figure 3-Figure 11 As shown, the embodiment of the present invention controls the duration T2 of the optical modulation element 10 in the non-transparent state to be greater than the duration T1 of the driving current of the light-emitting element 011 in a light-emitting stage. When the light-emitting element 011 is in the light-emitting state, the optical modulation element 10 is in the non-transparent state, which can block and absorb the wide-viewing angle display light in the display panel 200, avoid this part of the wide-viewing angle display light from passing through the back of the display panel 200, improve the problem of light leakage and halo on the back of the display module 300, and help to achieve invisible content on the back of the display module 300.

[0072] On the basis of the above-mentioned embodiment, reference Fig.11 In the light-emitting stage, the start time of the second state of the optical modulation element 10 is before the start time of the light-emitting stage. Figure 3-Figure 11 As shown, in an embodiment of the present invention, the starting moment of controlling the optical modulation element 10 to switch to the second state is earlier than the starting moment of the light-emitting element 011 working in the light-emitting stage, thereby ensuring that when the light-emitting element 011 emits light, the optical modulation element 10 has switched to the non-transparent state, ensuring that the optical modulation element 10 can block and absorb the wide-viewing angle display light in the display panel 200, thereby achieving invisible content on the back of the display module 300.

[0073] On the basis of the above-mentioned embodiment, reference Fig.11 In the light-emitting stage, the end time of the second state of the optical modulation element 10 is after the end time of the light-emitting stage. Figure 3-Figure 11As shown, in an embodiment of the present invention, the end time of controlling the optical modulation element 10 to switch to the second state is later than the end time of the light-emitting element 011 working in the light-emitting stage, thereby ensuring that when the light-emitting element 011 transitions from the light-emitting stage to the non-light-emitting stage, the optical modulation element 10 remains in a non-transparent state, thereby blocking and absorbing the residual wide-viewing angle display light in the display panel 200, thereby making the content on the back of the display module 300 invisible.

[0074] On the basis of the above-mentioned embodiment, reference Fig.11 , the time length of a light-emitting stage is T1, and the overlapping time length of the driving period of the optical modulation element 10 in the second state and the driving period of the light-emitting stage is greater than or equal to the time length T1 of the light-emitting stage. In other words, the embodiment of the present invention controls the time T2 of the optical modulation element 10 to remain in the second state to completely cover the light-emitting time T1 of the light-emitting element 011 working in the light-emitting stage, so as to ensure that when the light-emitting element 011 emits light, the optical modulation element 10 continues to remain in a non-transparent state, ensure that the residual large-viewing angle display light in the display panel 200 is blocked and absorbed, and realize that the content on the back of the display module 300 is invisible.

[0075] On the basis of the above embodiment, continue to refer to Fig.11 A driving cycle includes a light-emitting stage and a non-light-emitting stage. The time length of the driving cycle is T, and the time length of a light-emitting stage is T1, wherein T1≤50%T. T3 is the time length of a non-light-emitting stage, T=T1+T3.

[0076] It should be noted that when the optical modulation element 10 remains in the second state for a long time, it will affect the transparent display effect of the display panel. Therefore, the embodiment of the present invention controls the time length T1 of the light-emitting stage within a driving cycle of the light-emitting element to be no greater than the time length T of half a driving cycle. This can ensure that the light-emitting element has a high light efficiency. At the same time, on the basis of satisfying that the time length of the optical modulation element 10 in the second state covers the light-emitting time, the time length of the optical modulation element 10 in the second state is compressed as much as possible, so that the optical modulation element 10 can be maintained in the first state with a larger transmittance for a longer time, thereby increasing the light transmittance time of the display panel and improving the transparent display effect of the display panel.

[0077] Further, Fig.12 is another timing diagram of a light emitting control signal and a modulation control signal provided by the present invention, Fig.13 yes Figure 4 Another display effect schematic diagram of a display module is provided. In an embodiment of the present invention, reference is made to Fig.12, Emit1 is recorded as the light-emitting control signal of the light-emitting element 011, high level is light-emitting, low level is no light-emitting; Emit2 is recorded as the modulation control signal of the optical modulation element 10 in the second state, high level is transparent state, low level is non-transparent state. Figure 1-Figure 12 As shown in Table 1, the display module 300 can realize at least four modes, such as a transparent display mode, a non-transparent display mode, a transparent non-display mode, and a non-transparent non-display mode.

[0078] Table 1

[0079]

[0080]

[0081] The foreground refers to the scene behind the display module seen by user A from the light-emitting surface of the display module, and the background refers to the scene in front of the display module seen by user B from the backlight surface of the display module. The “×” indicates that it cannot be seen. The “√” indicates that it can be seen.

[0082] In transparent display mode: the refresh frequencies of the light emitting control signal Emit1 and the modulation control signal Emit2 are consistent. When the light emitting control signal Emit1 is at a high level, the light emitting element emits light; when the light emitting control signal Emit1 is at a low level, the light emitting element does not emit light. When the modulation control signal Emit2 is at a low level, the optical modulation element 10 is in a non-transparent state; when the modulation control signal Emit2 is at a high level, the optical modulation element 10 is in a transparent state.

[0083] The optical modulation element 10 is opaque only in the light-emitting stage, and transparent in the non-light-emitting stage. The display panel 200 still has a transparent period in the entire driving cycle. Usually, when the display panel 200 displays a frame, there are multiple light-emitting stages and non-light-emitting stages. The refresh rate of the display panel 200 is usually relatively high, such as 30HZ, 60HZ, 120HZ, etc. At such a high refresh rate, it is almost impossible to detect it with the naked eye. Figure 5 , Figure 6 During the entire lighting stage, the wide-angle display light S' cannot pass through the back of the display panel 200, but the background light S0 (ambient light) can still be seen by the user A through the display panel 200 when the optical modulation element 10 is in a non-transparent state, thereby realizing a transparent display mode. Figure 6 As shown in Table 1, in the transparent display mode, user A can see the display image and the foreground of the display module, and user B cannot see the display image but can see the background of the display module. At this time, the display effect of the display module 300 is the display content privacy mode.

[0084] In non-transparent display mode: the refresh frequencies of the light-emitting control signal Emit1 and the modulation control signal Emit2 are consistent. When the light-emitting control signal Emit1 is at a high level, the light-emitting element emits light; when the light-emitting control signal Emit1 is at a low level, the light-emitting element does not emit light. The modulation control signal Emit2 is continuously at a low level, and the optical modulation element 10 continues to maintain a non-transparent state. In other words, the optical modulation element 10 is non-transparent in both the light-emitting stage and the non-light-emitting stage, and the display panel 200 is non-transparent throughout the entire driving cycle. Figure 5 and Fig.13 In this non-transparent display mode, the wide-angle display light S' cannot pass through the back of the display panel 200 during the entire luminous stage and the non-luminous stage. User A can see the display image but cannot see the foreground image of the display module 300. User B cannot see the display image or the background image of the display module 300. At this time, the display effect of the display module 300 is a high-contrast mode.

[0085] In the transparent non-display mode, the refresh frequencies of the light-emitting control signal Emit1 and the modulation control signal Emit2 are consistent, the light-emitting control signal Emit1 is continuously at a low level, the light-emitting element does not emit light, the display panel 200 works in the non-light-emitting stage, and the display panel 200 does not display; the modulation control signal Emit2 is continuously at a high level, and the optical modulation element 10 is continuously in a transparent state. Figure 4 , the optical modulation element 10 continues to be transparent during the entire driving cycle of the display panel 200. It can be understood that the display module 300 at this time only has a transparent function. Figure 6 and Fig.13 User A cannot see the displayed image but can see the foreground image of the display module 300, user B cannot see the displayed image but can see the background image of the display module 300, and the display effect of the display module 300 is only transparent.

[0086] In the non-transparent non-display mode, the refresh frequencies of the light-emitting control signal Emit1 and the modulation control signal Emit2 are consistent, the light-emitting control signal Emit1 is continuously at a low level, the light-emitting element does not emit light, the display panel 200 works in the non-light-emitting stage, and the display panel 200 does not display; the modulation control signal Emit2 is continuously at a low level, and the optical modulation element 10 is continuously in a non-transparent state. The display module 300 is in the non-transparent non-display mode. Figure 6 and Fig.13 It can be understood that the display module 300 is not a transparent display screen, user A cannot see the displayed image or the foreground image of the display module 300, user B cannot see the displayed image or the background image of the display module 300, and the display effect of the display module 300 is background privacy.

[0087] Fig.14The present invention provides a schematic diagram of the structure of an optical modulation element. Fig.14 The optical modulation element 10 includes a first electrode layer 10a, an electrochromic material 10b and a second electrode layer 10c which are stacked. The electrochromic material 10b is in an oxidized state in the first state and in a reduced state in the second state.

[0088] Among them, the electrochromic material 10b is a material that can undergo reversible color change under the action of an external electric field. Under the action of an electric field, the optical properties (such as transmittance, reflectivity, absorptivity, etc.) of this material will change, thereby showing different colors or transparencies. The redox reaction can be metal oxides, such as WO3 (tungsten trioxide), NiO (nickel oxide), MoO3 (molybdenum trioxide), etc. The electrochromic phenomenon usually involves redox reactions, ion insertion / extraction and other processes.

[0089] In the embodiment of the present invention, a voltage is applied to the first electrode layer 10a and the second electrode layer 10c by utilizing the redox reaction of the electrochromic material 10b. In the first state, the electrochromic material 10b is controlled to undergo an oxidation reaction to become an oxidized state, and the optical modulation element 10 is in a transparent state, such as Fig.14 In the second state, the electrochromic material 10b is controlled to undergo a reduction reaction to become a reduced state, and the optical modulation element 10 appears in a non-transparent state or a semi-transparent state, as shown in FIG. Fig.14 The embodiment of the present invention controls the non-transparent state of the electrochromic material to block and absorb the wide viewing angle display light in the display panel, thereby improving the light leakage and halo problems on the back of the display module and improving the transparent display effect of the display module.

[0090] Fig.15 The present invention provides a schematic diagram of the structure of an optical modulation element. Fig.15 The optical modulation element 10 includes a first electrode layer 10d, a liquid crystal layer 10e, and a second electrode layer 10f which are stacked; the liquid crystal layer 10e is in a transparent state in a first state and in a scattering state in a second state.

[0091] The liquid crystal molecules in the liquid crystal layer 10e are anisotropic and can change their arrangement direction under the action of an external electric field. In the embodiment of the present invention, an electric field is applied to the liquid crystal molecules by the first electrode layer 10d and the second electrode layer 10f to control the arrangement and orientation of the liquid crystal molecules to adjust the transmittance of light, thereby realizing the transparent state of the optical modulation element 10. For example, in the first state, a high voltage difference is controlled between the first electrode layer 10d and the second electrode layer 10f, so that the liquid crystal molecules in the liquid crystal layer 10e are arranged in the same direction, the transmittance of the liquid crystal molecules to light is low, and the optical modulation element 10 is in a transparent state, such as Fig.15In the second state, the voltage difference between the first electrode layer 10d and the second electrode layer 10f is controlled to be low, the liquid crystal molecules in the liquid crystal layer 10e are arranged in a disordered direction, the light transmittance of the liquid crystal molecules is low, and the optical modulation element 10 exhibits a high scattering state, as shown in FIG. Fig.15 (b) As shown. Among them, the high scattering state can disrupt and absorb the wide viewing angle display light in the display panel, improve the light leakage and halo problems on the back of the display module, and thus improve the transparent display effect of the display module.

[0092] Fig.16 The present invention provides a schematic diagram of the structure of an optical modulation element. Fig.16 The optical modulation element 10 includes a first electrode layer 10g, a microlens structure 10h and a second electrode layer 10i which are stacked; the microlens structure 10h is transparent in the first state and is highly reflective in the second state.

[0093] The microlens structure 10h used in the embodiment of the present invention is a lens array or a single lens with a tiny size (usually in the micrometer to millimeter level) that can focus, diverge or modulate light.

[0094] In the embodiment of the present invention, the first electrode layer 10d and the second electrode layer 10f apply an electric field to the microlens structure 10h to control the arrangement angle and direction of the microlens structure 10h to adjust the light transmittance, thereby adjusting the transparent state of the optical modulation element 10. For example, in the first state, the voltage of the first electrode layer 10g and the second electrode layer 10i is controlled to change the shape angle of the microlens structure 10h to be consistent in the horizontal direction, and adjust its light transmittance to be higher, and the optical modulation element 10 is in a transparent state, such as Fig.16 In the second state, the voltage of the first electrode layer 10d and the second electrode layer 10f is controlled to change the shape angle of the microlens structure 10h to be consistent along the vertical direction, and adjust its reflectivity to light to be higher, and the optical modulation element 10 is in a high reflective state, as shown in FIG. Fig.16 (b) As shown. Among them, the high reflective state can reflect and absorb the large viewing angle display light in the display panel, improve the problem of light leakage and halo on the back of the display module, and thus improve the transparent display effect of the display module.

[0095] Based on the above embodiments, Figure 14-16 The first electrode layer and the second electrode layer can use transparent electrodes, such as ITO (indium tin oxide) electrodes, etc., which is conducive to achieving a completely transparent state of the optical modulation element 10.

[0096] Among them, Table 2 is the Figure 14-16 The optical modulation element 10 shown in the figure shows the difference in display effect. Figure 6The viewing effect of user A and user B in Figure 14-16 The optical modulation element 10 shown, the display module 300 switches the optical modulation element 10 to the second state during the light-emitting stage, wherein the second state can be any one of a non-transparent state, a high-scattering state, and a high-reflection state. When the display module 300 is in the transparent display mode, user A can see both the display image and the foreground image of the display module; user B cannot see the display image, but can see the background image, thus achieving the transparent display effect of the display module and avoiding the problem of leakage and halo of the display image on the back of the display module 300.

[0097] Table 2

[0098]

[0099] Based on the same inventive concept, an embodiment of the present invention further provides a display device. Fig.17 A schematic diagram of the structure of a display device provided by an embodiment of the present invention. Fig.17 As shown, the display device 400 includes any display module 300 provided in the above embodiments. Therefore, the display device 17 also has the beneficial effects of the display module 300 in the above embodiments, and the similarities can be understood by referring to the above explanation of the display module 300, which will not be repeated below.

[0100] The display device 400 provided in the embodiment of the present invention can be Fig.17 The mobile phone shown can also be any electronic product with a display function, including but not limited to the following categories: televisions, laptops, desktop displays, tablet computers, digital cameras, smart bracelets, smart glasses, car displays, industrial control equipment, medical display screens, touch interactive terminals, etc. The embodiments of the present invention do not specifically limit this.

[0101] Note that the above are only preferred embodiments of the present invention and the technical principles used. Those skilled in the art will understand that the present invention is not limited to the specific embodiments described herein, and that various obvious changes, readjustments and substitutions can be made by those skilled in the art without departing from the scope of protection of the present invention. Therefore, although the present invention has been described in more detail through the above embodiments, the present invention is not limited to the above embodiments, and may include more other equivalent embodiments without departing from the concept of the present invention, and the scope of the present invention is determined by the scope of the appended claims.

Claims

1. A display module, characterized in that: include: A display panel including a pixel area and a non-pixel area; An optical modulation element, at least located in the non-pixel area; The working process of the display panel includes at least one light-emitting stage and at least one non-light-emitting stage; the working state of the optical modulation element includes a first state and a second state; the transmittance of the optical modulation element in the first state is greater than the transmittance of the optical modulation element in the second state; During the light emitting phase, the optical modulation element is in a second state.

2. The display module according to claim 1, characterized in that: The first state is a transparent state, and the second state is a non-transparent state.

3. The display module according to claim 1, characterized in that: In the non-light-emitting stage, the optical modulation element is in the first state or the second state.

4. The display module according to claim 1, characterized in that: The optical modulation element is located at the backlight side of the display module; wherein the backlight side is opposite to the light emitting surface of the display module.

5. The display module according to claim 4, characterized in that: The optical modulation element is also located in the pixel area.

6. The display module according to claim 4, characterized in that: The optical modulation element includes a modulation area and a blocking area; the modulation area is located in the non-pixel area, the blocking area is located in the pixel area, and the modulation area includes the first state and the second state.

7. The display module according to claim 1, characterized in that: The display module also includes a base substrate, and a driving circuit layer, a plurality of light-emitting elements and a planarization layer sequentially located on one side of the base substrate; the optical modulation element is located between the driving circuit layer and the planarization layer in the non-pixel area.

8. The display module according to claim 1, characterized in that: An optical modulation frequency of switching the optical modulation element between the first state and the second state is the same as a refresh frequency of switching between the light emitting stage and the non-light emitting stage.

9. The display module according to claim 1, characterized in that: The duration of one of the light emitting stages is T1, and the duration of the optical modulation element being in the second state is T2; wherein T1<T2.

10. The display module according to claim 1, characterized in that: In the light emitting stage, the starting time of the second state of the optical modulation element is before the starting time of the light emitting stage.

11. The display module according to claim 1, characterized in that: In the light emitting stage, the end time of the second state of the optical modulation element is located after the end time of the light emitting stage.

12. The display module according to claim 1, characterized in that: The duration of one of the light emitting stages is T1, and the overlapping duration of the driving period of the optical modulation element in the second state and the driving period of the light emitting stage is greater than or equal to the duration T1 of the light emitting stage.

13. The display module according to claim 1, characterized in that: One driving cycle includes one luminous phase and one non-luminous phase. The duration of the driving cycle is T, and the duration of one luminous phase is T1, wherein T1≤50%T.

14. The display module according to any one of claims 1 to 13, characterized in that: The optical modulation element comprises a first electrode layer, an electrochromic material and a second electrode layer which are stacked; the electrochromic material is in an oxidized state in the first state and in a reduced state in the second state.

15. The display module according to any one of claims 1 to 13, characterized in that: The optical modulation element comprises a first electrode layer, a liquid crystal layer and a second electrode layer which are stacked; the liquid crystal layer is in a transparent state in the first state and in a scattering state in the second state.

16. The display module according to any one of claims 1 to 13, characterized in that: The optical modulation element comprises a first electrode layer, a microlens structure and a second electrode layer which are stacked; the microlens structure is in a transparent state in the first state and in a highly reflective state in the second state.

17. The display module according to claim 1, characterized in that: The non-pixel region includes a plurality of transparent film layers, and the transmittance of the optical modulation element in the first state is greater than or equal to the transmittance of the plurality of transparent film layers.

18. A display device, characterized in that: A display module comprising any one of claims 1-17.

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