CN112198709B

CN112198709B - Liquid crystal display device and method for driving the same

Info

Publication number: CN112198709B
Application number: CN202011088935.1A
Authority: CN
Inventors: 钟德镇; 廖家德; 刘显贺; 沈家军
Original assignee: InfoVision Optoelectronics Kunshan Co Ltd
Current assignee: InfoVision Optoelectronics Kunshan Co Ltd
Priority date: 2020-10-13
Filing date: 2020-10-13
Publication date: 2022-09-23
Anticipated expiration: 2040-10-13
Also published as: CN112198709A

Abstract

A liquid crystal display device and its driving method, the liquid crystal display device includes display panel, first light modulator, backlight module and second light modulator, the second light modulator is used for scattering the light; the first dimmer includes a first electrode, a second electrode, and a first liquid crystal layer; the backlight module is a light-collecting backlight module, and the second light modulator is arranged between the first liquid crystal layer of the first light modulator and the backlight module; or, the liquid crystal display device further comprises a third light modulator, the third light modulator is used for receiving emergent light of the backlight module, the second light modulator is arranged between the first liquid crystal layer of the first light modulator and the backlight module, and the light receiving direction of the third light modulator corresponds to the light scattering direction of the second light modulator. According to the liquid crystal display device and the driving method thereof disclosed by the embodiment, narrow viewing angle display with high contrast can be realized under narrow viewing angle display, and the peep-proof effect is good; the second light modulator is matched for light scattering under the wide-view-angle display, so that a good wide-view-angle display effect can be ensured.

Description

Liquid crystal display device and driving method thereof

Technical Field

The invention relates to the technical field of display, in particular to a liquid crystal display device and a driving method thereof.

Background

With the progress of social economy and science and technology, users of display devices have different visual requirements for shareability and confidentiality data, and the display devices with single view angle mode have been unable to meet the requirements of users. Therefore, a need for switching between wide and narrow viewing angle modes is raised for the liquid crystal display panel, and when a user needs to share information, the wide viewing angle mode is opened; when the user wants to protect the displayed information, the narrow viewing angle mode is used.

In the prior art, the following three methods exist to realize the switching of the wide and narrow viewing angle modes:

1. in the shutter technology, a narrow viewing angle is realized by externally attaching a diaphragm, and when a wide viewing angle mode is required, the diaphragm needs to be torn off, so that flexible switching cannot be realized;

2. the pixel division technology divides one sub-pixel into two parts, sacrifices the expressive ability of wide-view display, and increases the driving power consumption and the manufacturing cost;

3. in a narrow visual angle mode, the pixel electrode and the common electrode control display, and the whole bias voltage is applied between the common electrode and the visual angle control electrode, so that liquid crystal molecules tilt to form light leakage under a large visual angle, and the peep-proof effect is achieved; however, the dark state brightness is higher in the narrow viewing angle mode, which causes a decrease in contrast ratio, and the display effect and the anti-peeping effect are affected by the whitening of both sides of the panel and the gray scale inversion at a certain viewing angle during the front view.

The foregoing description is provided for general background information and is not admitted to be prior art.

Disclosure of Invention

The invention aims to provide a liquid crystal display device with switchable wide and narrow visual angles and a driving method thereof.

The invention provides a liquid crystal display device, which comprises a display panel, a first light modulator, a backlight module and a second light modulator, wherein the display panel and the first light modulator are arranged on the light emergent side of the backlight module; the first dimmer comprises a first electrode, a second electrode and a first liquid crystal layer, wherein the first liquid crystal layer is positioned between the first electrode and the second electrode;

the backlight module is a light-collecting backlight module and is used for emitting light and collecting the light, and the second light modulator is arranged between the first liquid crystal layer of the first light modulator and the backlight module; or, the liquid crystal display device still includes the third light modulator, the third light modulator is used for right backlight unit's emergent light is received light, the second light modulator is located first light modulator the first liquid crystal layer with between the third light modulator, the light direction of receiving of third light modulator with the astigmatism direction of second light modulator corresponds.

Further, the third dimmer is capable of four-way light collection; or, the light-collecting type backlight module can collect light in all directions.

Further, when the third light modulator is used for four-way light receiving, the third light modulator comprises a first light modulation strip and a second light modulation strip, the extending direction of the first light modulation strip is perpendicular to the extending direction of the second light modulation strip, the extending direction of the first light modulation strip is parallel to the left-right direction of the liquid crystal display device, and the extending direction of the second light modulation strip is parallel to the up-down direction of the liquid crystal display device.

Further, the second dimmer comprises a first light-scattering bar extending in a first direction and a second light-scattering bar extending in a second direction;

the first direction is perpendicular to the second direction, the first direction is the up-down direction or the left-right direction of the liquid crystal display device, and the second direction is the left-right direction or the up-down direction of the liquid crystal display device; or the first direction is perpendicular to the second direction, the included angle between the first direction and the left-right direction of the liquid crystal display device is 45 degrees, and the included angle between the second direction and the left-right direction of the liquid crystal display device is also 45 degrees; or the first direction is perpendicular to the second direction, and the included angle between the first direction and the left and right directions of the liquid crystal display device is 20-60 degrees; or the included angle between the first direction and the left and right direction of the liquid crystal display device is 20-60 degrees, and the included angle between the first direction and the second direction is 45-135 degrees.

Further, when the first direction is perpendicular to the second direction, the first direction is a vertical direction of the liquid crystal display device, and the second direction is a horizontal direction of the liquid crystal display device, the area occupied by the first light scattering bars is larger than the area occupied by the second light scattering bars, and the first light modulator receives light from left and right; or, when the first direction is perpendicular to the second direction, the first direction is the up-down direction of the liquid crystal display device, and the second direction is the left-right direction of the liquid crystal display device, the area occupied by the first light scattering bars is smaller than the area occupied by the second light scattering bars, and the first light modulator receives light up and down.

Furthermore, the third light modulator or the light-collecting backlight module receives light in a left-right direction, the second light modulator only comprises a first light-scattering strip, the extending direction of the first light-scattering strip is parallel to the vertical direction of the liquid crystal display device, and the second light modulator scatters light in the left-right direction; or, the third light modulator or the light-collecting type backlight module is used for receiving light in an up-down direction, the second light modulator only comprises a second light scattering strip, the extending direction of the second light scattering strip is parallel to the left-right direction of the liquid crystal display device, and the second light modulator scatters light in the up-down direction.

Furthermore, the display panel is arranged between the first dimmer and the backlight module; or the first dimmer is arranged between the display panel and the backlight module; or the second dimmer is arranged on the display panel and/or the first dimmer.

Furthermore, the liquid crystal display device further comprises a first polarizing plate, a second polarizing plate and a third polarizing plate, the first polarizing plate is located on the light incident side of the liquid crystal display device, the third polarizing plate is located on the light emergent side of the liquid crystal display device, and the second polarizing plate is located between the first dimmer and the display panel; the transmission axis directions of the polarizing plates on both sides of the display panel are perpendicular to each other, and the transmission axis directions of the polarizing plates on both sides of the first light modulator are parallel to each other.

Furthermore, the second polarizing plate comprises a polarizing film and a brightness enhancement film which are overlapped, and the bright surface of the brightness enhancement film faces to and is far away from one side of the backlight module; or the display panel is positioned on the upper side of the first dimmer, and the second polarizing plate is an anti-dazzle polarizing plate.

The present invention also provides a driving method of the liquid crystal display device, including: when the liquid crystal display device is in a wide viewing angle display mode, a first voltage of 0V is applied to the second electrode, a second voltage is applied to the first electrode, the waveform of the second voltage is a pulse wave, and the waveform of the second voltage is as follows: the picture refreshing cycle of the liquid crystal display device is 2t, the voltage value of the second voltage in a time period of t1 is A, and the voltage value in a time period of t2 is-A, wherein t1 is t2 (1/3-1/2) t, and A is 2V-4V; when the liquid crystal display device is in a narrow visual angle display mode, 0V voltage is applied to the second electrode, alternating current voltage is applied to the first electrode, and the brightness of the backlight module is controlled to be lower than that in a wide visual angle display mode.

According to the liquid crystal display device and the driving method thereof disclosed by the embodiment, light can be received by arranging the light-collecting type backlight module or arranging the third light modulator on the common backlight module, and a narrow-view-angle display mode with higher contrast can be realized by matching the first light modulator, so that the peep-proof effect is better; the light-adjusting microstructure of the second light adjuster is matched to scatter light in the wide visual angle display mode, so that the liquid crystal display device can have a good wide visual angle display effect.

Drawings

Fig. 1 is a schematic structural diagram of a liquid crystal display device according to a first embodiment of the invention.

Fig. 2 is a schematic structural diagram of a second embodiment of the second dimmer of the lcd device shown in fig. 1.

Fig. 3 is a schematic structural diagram of a second embodiment of a second dimmer of the lcd device shown in fig. 1.

Fig. 4 is a schematic structural diagram of a third dimmer of the liquid crystal display device shown in fig. 1.

FIG. 5 is a waveform diagram of an embodiment of an input voltage of the first electrode of the LCD device shown in FIG. 1.

FIG. 6 is a waveform diagram of an input voltage of the first electrode of the LCD device shown in FIG. 1 according to another embodiment.

Fig. 7a is a schematic diagram illustrating a contrast simulation of the first electrode of the lcd shown in fig. 1 when the waveform voltage shown in fig. 5 is applied to the first electrode in the wide viewing angle mode.

Fig. 7b is a diagram illustrating contrast ratio simulation of the first electrode of the lcd device shown in fig. 1 when the waveform voltage shown in fig. 6 is applied in the wide viewing angle mode.

Fig. 7c is a diagram illustrating contrast ratio simulation when a voltage of an ac square wave having an amplitude of 10V is applied to the first electrode of the lcd device shown in fig. 1 in a wide viewing angle mode.

Fig. 8 is a schematic structural diagram of a third embodiment of a second dimmer of the liquid crystal display device shown in fig. 1.

Fig. 9 is a schematic structural diagram of a fourth embodiment of a second dimmer of the liquid crystal display device shown in fig. 1.

Fig. 10 is a schematic structural diagram of a fifth embodiment of a second dimmer of the liquid crystal display device shown in fig. 1.

Fig. 11 is a schematic structural diagram of a liquid crystal display device according to a second embodiment of the invention.

Fig. 12 is a schematic structural diagram of a liquid crystal display device according to a third embodiment of the invention.

Fig. 13 is a schematic structural diagram of a liquid crystal display device according to a fourth embodiment of the invention.

Fig. 14 is a schematic structural view of a liquid crystal display device according to a fifth embodiment of the present invention.

Fig. 15 is a schematic structural view of a liquid crystal display device according to a sixth embodiment of the present invention.

Detailed Description

The following detailed description of the present invention is provided in connection with the accompanying drawings and examples. The following examples are intended to illustrate the invention, but are not intended to limit the scope of the invention.

First embodiment

Fig. 1 is a schematic view showing a structure of a liquid crystal display device according to a first embodiment of the present invention. Referring to fig. 1, the lcd device of the first embodiment includes a display panel 10, a first light modulator 30 and a backlight module 40, wherein the display panel 10 and the first light modulator 30 are disposed on a light emitting side of the backlight module 40. The display panel 10 includes a second dimmer 101. In the present embodiment, the display panel 10 is disposed between the first light modulator 30 and the backlight module 40. The first dimmer 30 is used for left and right dimming. Of course, the first dimmer 30 may also be used for upper and lower light collection. Specifically, the display panel 10 and the first light modulator 30 may be attached by a frame attaching method or a full attaching method.

In this embodiment, the backlight module 40 is provided with a third light modulator 50, the third light modulator 50 is used for narrowing the emergent light of the backlight module 40, the second light modulator 101 of the display panel 10 is used for diverging the light narrowed by the third light modulator 50, and the light converging direction of the third light modulator 50 corresponds to the light diverging direction of the second light modulator 101. When the third light modulator 50 is disposed, a common backlight module may be used, which may reduce the manufacturing cost of the liquid crystal display device.

In this embodiment, the second light modulator 101 may be a light modulation prism, and the third light modulator 50 may be a privacy layer.

In this embodiment, referring to fig. 2, the second light modulator 101 includes a first light scattering strip 1012 extending along a first direction and a second light scattering strip 1014 extending along a second direction, the first direction is perpendicular to the second direction, the first direction is a vertical direction of the liquid crystal display device, and the second direction is a horizontal direction of the liquid crystal display device. More specifically, the first light dispersion strips 1012 occupy a larger area than the second light dispersion strips 1014. When the area occupied by the first light scattering bars 1012 is larger than the area occupied by the second light scattering bars 1014, the scattering ability of the second light modulator 101 in the up-down direction of light is weaker than that in the left-right direction, so that a better narrow viewing angle effect in the up-down direction can be realized under the action of the third light modulator 50 for peeping prevention and with the brightness adjustment of the backlight module, thereby ensuring a display effect of four-way peeping prevention. Preferably, the ratio of the area occupied by the first light diffusing strips 1012 to the area occupied by the second light diffusing strips 1014 is 2: 1. Specifically, the first and second

light dispersing strips

1012, 1014 can be formed by a mold machining, mechanical forming, or photo etching process.

Referring to fig. 3, in another embodiment, the second light modulator 101 includes a first light scattering strip 1012 extending along a first direction and a second light scattering strip 1014 extending along a second direction, the first direction is perpendicular to the second direction, and an angle between the first direction and a left-right direction of the liquid crystal display device is 45 °, and an angle between the second direction and the left-right direction of the liquid crystal display device is also 45 °.

It is understood that the extending direction of the first light scattering bars 1012 can also form other angles with the left and right direction of the liquid crystal display device, for example, 20 to 60 degrees, and the second light scattering bars 1014 need to be perpendicular to the first light scattering bars 1012 in order to better realize the peep prevention in the up, down, left and right directions. Of course, the second light diffusion strips 1014 may not be perpendicular to the first light diffusion strips 1012, and the included angle thereof is preferably 45 ° to 135 °.

It is understood that the second light modulator 101 may be disposed on the first light modulator 30 and located on a side of the first liquid crystal layer 308 close to the display panel 10. The second dimmer 101 may also be provided on both the display panel 10 and the first dimmer 30. That is, the second light modulator 101 may be disposed on the side of the first liquid crystal layer 308 close to the backlight module 40, i.e., the first light modulator 30 receives light after the light is diffused by the second light modulator 101. The second light modulator 101 is preferably located on a side of the display panel 10 close to the backlight module 40 in this embodiment.

In this embodiment, the third light modulator 50 is disposed on the backlight module 40. It is understood that the third light modulator 50 may also be disposed on a side of the display panel 10 close to the backlight module 40.

In this embodiment, referring to fig. 4, the third light modulator 50 can receive light in four directions. Specifically, the third light modulator 50 includes a first light modulation bar 502 and a second light modulation bar 504, an extending direction of the first light modulation bar 502 is perpendicular to an extending direction of the second light modulation bar 504, the extending direction of the first light modulation bar 502 is parallel to a left-right direction of the liquid crystal display device, and the extending direction of the second light modulation bar 504 is parallel to an up-down direction of the liquid crystal display device. It is to be understood that the extending direction of the first light-adjusting bar 502 may not be perpendicular to the extending direction of the second light-adjusting bar 504, the extending direction of the first light-adjusting bar 502 may not be parallel to the left-right direction of the liquid crystal display device, and the extending direction of the second light-adjusting bar 504 may not be parallel to the up-down direction of the liquid crystal display device, as long as the first light-adjusting bar 502 intersects with the second light-adjusting bar 504. The first and second light-adjusting

bars

502 and 504 extending in two different directions can receive light in four directions, i.e., up, down, left, and right, of the third light modulator 50. Specifically, the third dimmer 50 may further include an upper plate 506 and a lower plate 508, and the first and second dimming bars 502 and 504 are disposed between the upper plate 506 and the lower plate 508, and more specifically, the first and second dimming bars 502 and 504 are stacked between the upper plate 506 and the lower plate 508. It is understood that the first and second light-adjusting

bars

502, 504 may be disposed in the same layer.

It is understood that, in other embodiments, the backlight module 40 may be configured as a light-collecting type backlight module, and the light-collecting type backlight module can collect light in four directions. In this case, the third light modulator 50 may be omitted and the backlight module 40 may receive light. Of course, in other embodiments, the third light modulator 50 may be configured with a light-collecting backlight module.

The first dimmer 30 includes a first substrate 302, a first electrode 303, a second substrate 305, a second electrode 306, and a first liquid crystal layer 308. The first liquid crystal layer 308 is sandwiched between the first substrate 302 and the second substrate 305. A first electrode 303 and a second electrode 306 are provided on the first substrate 302 and the second substrate 305, respectively. In this embodiment, the first electrode 303 is close to the first liquid crystal layer 308 with respect to the first substrate 302, and the second electrode 306 is close to the first liquid crystal layer 308 with respect to the second substrate 305. Specifically, the first electrode 303 is closer to the backlight assembly 40 than the second electrode 306. The first electrode 303 is further provided with a protective layer 309 on the side close to the first liquid crystal layer 308. The protection layer 309 may also be located on the side of the second electrode 306 close to the first liquid crystal layer 308. The protective layer 309 is used to prevent short circuit caused by a short distance between upper and lower electrodes. In the present embodiment, the first liquid crystal layer 308 employs positive liquid crystal molecules. It is understood that the first liquid crystal layer 308 may also employ negative liquid crystal molecules.

The display panel 10 further includes a first substrate 102, a second substrate 104, and a second liquid crystal layer 106 disposed between the first substrate 102 and the second substrate 104. The first substrate 102 may be an array substrate, which includes a third substrate 1022, a thin film transistor (not shown), a common electrode 1024, and a pixel electrode 1026, where a plurality of pixel units are defined by the scan lines and the data lines, and each pixel unit includes one pixel electrode 1026 and one thin film transistor. The common electrode 1024 and the pixel electrode 1026 are insulated from each other. Specifically, in the present embodiment, the common electrode 1024 and the pixel electrode 1026 are located at different layers, and a first insulating layer 1027 is interposed between the common electrode and the pixel electrode. The pixel electrode 1026 is provided above the common electrode 1024, the pixel electrode 1026 is a slit-shaped electrode, and the common electrode 1024 is a planar electrode covering the entire surface of the third substrate 1022. The second substrate 104 may be a color filter substrate, and the color filter substrate includes a fourth substrate 1042 and a color resist 1044 disposed on the fourth substrate 1042. The color-resist layer 1044 is, for example, R, G, B color resist. A color resistance layer 1044 is provided on a surface of the fourth substrate 1042 on a side close to the second liquid crystal layer 106. A Black Matrix (BM) may be disposed between the color resists of the color resist layer 1044 to prevent light of different colors from being mixed. The second liquid crystal layer 106 may be a horizontally aligned liquid crystal, a vertically aligned liquid crystal, a Twisted Nematic (TN) liquid crystal, or other liquid crystal display technologies, which are not described in detail herein. Also, in the present embodiment, the second liquid crystal layer 106 employs positive liquid crystal molecules. It is to be understood that the second liquid crystal layer 106 may also employ negative liquid crystal molecules.

Specifically, the second dimmer 101 is disposed on the third substrate 1022, and the first flat layer 1029 is disposed on the second dimmer 101, and the common electrode 1024 is disposed on the first flat layer 1029.

In this embodiment, the second dimmer 101 includes first and second

light diffusion strips

1012 and 1014 per region corresponding to each pixel unit, and the first light diffusion strip 1012 occupies a larger area than the second light diffusion strip 1014 in the region corresponding to each pixel unit. Preferably, in the region corresponding to each pixel unit, the ratio of the area occupied by the first light diffusion stripes 1012 to the area occupied by the second light diffusion stripes 1014 is 2: 1.

In this embodiment, the liquid crystal display device further includes a first polarizing plate 60, a second polarizing plate 70 and a third polarizing plate 80, the first polarizing plate 60 is located on the light incident side of the liquid crystal display device, that is, on the side of the display panel 10 away from the first light modulator 30, the second polarizing plate 70 is located between the first light modulator 30 and the display panel 10, and the third polarizing plate 80 is located on the light emergent side of the liquid crystal display device, that is, on the side of the first light modulator 30 away from the display panel 10. The transmission axis directions of the polarizing plates at both sides of the display panel 10 are perpendicular to each other, and the transmission axis directions of the polarizing plates at both sides of the first light modulator 30 are parallel to each other. Specifically, the transmission axis direction of the first polarizing plate 60 is perpendicular to the transmission axis direction of the second polarizing plate 70, and the transmission axis direction of the second polarizing plate 70 is parallel to the transmission axis direction of the third polarizing plate 80. Specifically, in the present embodiment, the first polarizing plate 60 is disposed on the third substrate 1022 on the side away from the first light modulator 30, the second polarizing plate 70 is disposed on the first substrate 302 on the side away from the first liquid crystal layer 308, and the third polarizing plate 80 is disposed on the second substrate 305 on the side away from the first liquid crystal layer 308. It is to be understood that the second polarizing plate 70 may also be disposed on the side of the fourth substrate 1042 away from the second liquid crystal layer 106.

In this embodiment, the second polarizing plate 70 includes a polarizing film and a brightness enhancement film (i.e., the second polarizing plate 70 is APF POL) stacked together, and the brightness enhancement film may be disposed on a side of the polarizing film close to the backlight module 40 or on a side of the polarizing film away from the backlight module 40. The bright surface of the brightness enhancement film is disposed toward and away from one side of the backlight module 40. By disposing the brightness enhancement film on the second polarizer 70, the wide viewing angle display effect can be improved by using the mirror reflection thereof, and a better peep-proof effect can be achieved.

The present invention also provides a driving method of the liquid crystal display device, including:

s11, when the liquid crystal display device is in the wide viewing angle display mode, a first voltage of 0V is applied to the second electrode 306, and a second voltage having a pulse waveform is applied to the first electrode 303. Specifically, referring to fig. 5 and 6, when the screen refresh period of the liquid crystal display device is 2t (i.e., the time of one frame of the liquid crystal display period is 2t), the voltage value of the second voltage is a in the time period of t1, and the voltage value is-a in the time period of t2, where t1 is t2 is (1/3-1/2) t, and a is 2V-4V. In fig. 5, a is 2V, t1 is t2 is 1/3t, in fig. 6 a is 3V, and t1 is t2 is 1/3 t. In one embodiment, t is 3.33 ms. By applying the second voltage with a special waveform to the first electrode 303, the liquid crystal display device can have a wide viewing angle in a wide viewing angle mode, and has low power consumption, and the Trace Mura phenomenon of the liquid crystal display device can be improved.

Fig. 7a to 7c are schematic diagrams showing contrast simulation of the liquid crystal display device of the present embodiment when second voltages with different waveforms are applied in the wide viewing angle mode, respectively, fig. 7a is a schematic diagram showing contrast simulation of the liquid crystal display device of the present embodiment when the second voltage with the waveform shown in fig. 5 is applied in the wide viewing angle mode, fig. 7b is a schematic diagram showing contrast simulation of the liquid crystal display device of the present embodiment when the second voltage with the waveform shown in fig. 6 is applied in the wide viewing angle mode, and fig. 7c is a schematic diagram showing contrast simulation of the liquid crystal display device of the present embodiment when the second voltage with the ac square wave with the amplitude of 10V is applied in the wide viewing angle mode. Please refer to table 1 below, which is an optical parameter table of the liquid crystal display device of this embodiment when the second voltages with different waveforms are applied in the wide viewing angle mode. As can be seen from table 1, when the second voltage has the waveform shown in fig. 5, the wide viewing angle is wider in both the top, bottom, left, and right than the prior art, and when the second voltage has the waveform shown in fig. 6, the wide viewing angle is wider in both the top, bottom, left, and right than the prior art.

TABLE 1

S13, when the lcd device is in the narrow viewing angle display mode, a voltage of 0V is applied to the second electrode 306, an ac voltage is applied to the first electrode 303, and the luminance of the backlight module 40 is controlled to be lower than that in the wide viewing angle display mode. Specifically, the amplitude of the ac voltage may be 2V to 3V, and the waveform of the ac voltage may be a square wave. It is understood that the waveform of the ac voltage may be a sawtooth wave, a sine wave, or the like.

Through the liquid crystal display device of this embodiment, can receive the light through light-concentrating backlight unit or ordinary backlight unit collocation third light modulator, the higher narrow visual angle display mode of contrast can be realized to the first light modulator of collocation again, and the peep-proof effect is better, and the second light modulator of collocation carries out the astigmatism under wide visual angle display mode, can guarantee that liquid crystal display device has good wide visual angle display effect. Further, in this embodiment, since the third light modulator is provided with the first light modulation strip and the second light modulation strip extending in different directions, the liquid crystal display device can realize four-way peep prevention.

It is understood that in another embodiment, the third light modulator 50 may also include only the first light modulation bar 502 or the second light modulation bar 504, and the third light modulator 50 can only receive light in the up-down or left-right direction, so as to achieve bidirectional peeping prevention of the lcd device. When the third dimmer 50 includes only the first dimming strips 502 extending in the left-right direction of the liquid crystal display device, the third dimmer 50 can perform vertical dimming, and when the third dimmer 50 includes only the second dimming strips 504 extending in the vertical direction of the liquid crystal display device, the third dimmer 50 can perform horizontal dimming.

It can be understood that the liquid crystal display device of the invention can also realize the bilateral peep-proof or the up-down bilateral peep-proof. For the four-way peep-proof lcd device, the four-way peep-proof can be realized by using the third light modulator 50 (including the first light modulation strip 502 or the second light modulation strip 504 with different extending directions) for receiving light in four directions in combination with the first light modulator 30 for receiving light in left and right directions or in up and down directions. When the first light modulator 30 is used for up-and-down light emission, the second light modulator 101 shown in fig. 8 can be used, that is, the area occupied by the first light scattering bars 1012 is smaller than the area occupied by the second light scattering bars 1014, so as to achieve a good wide-angle display effect. Preferably, the ratio of the area occupied by the first light dispersion strip 1012 to the area occupied by the second light dispersion strip 1014 is 1: 2.

For the lcd device with left and right double-way peep prevention, the left and right double-way peep prevention can be achieved by using the third light modulator 50 (i.e. only including the second light modulation strip 504) for receiving light from left and right in combination with the first light modulator 30 for receiving light from left and right. In this case, the second light modulator 101 shown in fig. 9 may be used, that is, the second light modulator 101 only includes the first light scattering strip 1012, and the second light modulator 101 scatters light in the left and right directions, so as to ensure the wide viewing angle display effect at the left and right wide viewing angles.

For the up-down bidirectional peep-proof lcd device, the up-down bidirectional peep-proof can be realized by using the third light modulator 50 (i.e. only including the first peep-proof strip 502) for receiving light up and down in combination with the first light modulator 30 for receiving light up and down. At this time, the second light modulator 101 shown in fig. 10 may be used, that is, the second light modulator 101 only includes the second light scattering strip 1014, and the second light modulator 101 scatters light in the up-down direction, so as to ensure the wide viewing angle display effect at the wide viewing angle.

That is, in the case of the four-way peep-proof liquid crystal display device, the second light modulator 101 diffuses light in four directions, and the third light modulator 50 receives light in four directions, and in the case of the two-way peep-proof liquid crystal display device, the second light modulator 101 diffuses light in two directions, and the third light modulator 50 receives light in two directions, that is, the light diffusion direction of the second light modulator 101 corresponds to the light receiving direction of the third light modulator 50.

It is understood that when the backlight module 40 is configured as a light-collecting type backlight module and the third light modulator 50 is omitted, in the four-way anti-peeping and two-way anti-peeping lcd device, the light-collecting direction of the light-collecting type backlight module may be set to be the same as the light-collecting direction of the light-collecting type backlight module with the third light modulator 50.

Second embodiment

Fig. 11 is a schematic view showing a structure of a liquid crystal display device according to a second embodiment of the present invention. Referring to fig. 11, the structure of the liquid crystal display device of the present embodiment is similar to that of the liquid crystal display device of the first embodiment, except that in the present embodiment, the first light modulator 30 is disposed between the display panel 10 and the backlight module 40, and the second light modulator 101 is disposed on the first light modulator 30. The first polarizing plate 60 is disposed on a side of the first light modulator 30 away from the display panel 10, the second polarizing plate 70 is disposed between the first light modulator 30 and the display panel 10, and the third polarizing plate 80 is disposed on a side of the display panel 10 away from the first light modulator 30. Other structures of the liquid crystal display device of this embodiment are similar to those of the first embodiment, and are not described herein again.

In the present embodiment, since the display panel 10 is disposed on the upper side of the first light modulator 30, even when the waveforms shown in fig. 5 and 6 are not applied, the liquid crystal display device has a good Trace Mura performance, and the voltages of the first electrode and the second electrode can be 0V at a wide viewing angle of the first light modulator 30 disposed on the lower side of the display panel 10. In addition, the second polarizing plate 70 may be a general anti-glare polarizing plate (AG POL), i.e., the surface of the second polarizing plate 70 is treated, which can save power consumption and production cost.

Third embodiment

Fig. 12 is a schematic view showing a structure of a liquid crystal display device according to a third embodiment of the present invention. Referring to fig. 12, the structure of the liquid crystal display device of the present embodiment is similar to that of the liquid crystal display device of the first embodiment, except that in the present embodiment, the third light modulator 50 only includes the second light modulation strip (not shown in the figure), and the second light modulation strip extends along the vertical direction of the liquid crystal display device, so as to implement the bilateral peep prevention. In the present embodiment, the second dimmer 101 may be selected from any one of fig. 2, 3, 8, and 9. Other structures of the liquid crystal display device of this embodiment are similar to those of the first embodiment, and are not described herein again.

In other embodiments, the third light modulator 50 may also be located at a side of the first light modulator 30 close to the backlight module 40.

Fourth embodiment

Fig. 13 is a schematic view showing a structure of a liquid crystal display device according to a fourth embodiment of the present invention. Referring to fig. 13, the structure of the liquid crystal display device of the present embodiment is similar to that of the liquid crystal display device of the second embodiment, except that in the present embodiment, the third light modulator 50 only includes the second light modulation strip (not shown in the figure) extending along the up-down direction of the liquid crystal display device, so as to achieve bilateral peep prevention. In the present embodiment, the second dimmer 101 may be selected from any one of fig. 2, 3, 8, and 9. Other structures of the liquid crystal display device of this embodiment are similar to those of the second embodiment, and are not described again here.

In other embodiments, the third light modulator 50 may also be located on a side of the display panel 10 close to the backlight module 40.

Fifth embodiment

Fig. 14 is a schematic view showing a structure of a liquid crystal display device according to a fifth embodiment of the present invention. Referring to fig. 14, the structure of the liquid crystal display device of the present embodiment is similar to that of the liquid crystal display device of the fourth embodiment, except that in the present embodiment, the third light modulator 50 may be combined with the first polarizing plate 60 to form a composite film for use.

Specifically, the third light modulator 50 is disposed on the first light modulator 30 and is located on a surface of the first light modulator 30 close to the backlight module 40. Other structures of the liquid crystal display device of this embodiment are similar to those of the fourth embodiment, and are not described again here.

In other embodiments, when the display panel is disposed adjacent to the backlight module, the third light modulator is disposed on the display panel and on a surface of the display panel near a side of the backlight module.

Sixth embodiment

Fig. 15 is a schematic view showing a structure of a liquid crystal display device according to a sixth embodiment of the present invention. Referring to fig. 15, the structure of the liquid crystal display device of the present embodiment is similar to that of the liquid crystal display device of the second embodiment, except that in the present embodiment, the third light modulator 50 is not provided, and a light-collecting type backlight module is adopted. In the present embodiment, the second dimmer 101 may be selected from any one of fig. 2, 3, 8, and 9. Other structures of the liquid crystal display device of this embodiment are similar to those of the fourth embodiment, and are not repeated herein.

The above description is only for the specific embodiments of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art can easily think of the changes or substitutions within the technical scope of the present invention, and shall cover the scope of the present invention.

Claims

1. The liquid crystal display device is characterized by comprising a display panel (10), a first light modulator (30), a backlight module (40) and a second light modulator (101), wherein the display panel (10) and the first light modulator (30) are arranged on the light emitting side of the backlight module (40), and the second light modulator (101) is used for scattering light; the first dimmer (30) comprises a first electrode (303), a second electrode (306) and a first liquid crystal layer (308), the first liquid crystal layer (308) being located between the first electrode (303) and the second electrode (306);

the backlight module (40) is a light-collecting backlight module and is used for emitting light and collecting the light, the second light modulator (101) is arranged between the first liquid crystal layer (308) of the first light modulator (30) and the backlight module (40), and the light-collecting backlight module can collect the light in four directions; or, the liquid crystal display device further comprises a third light modulator (50), the third light modulator (50) is used for receiving light emitted by the backlight module (40), the second light modulator (101) is arranged between the first liquid crystal layer (308) of the first light modulator (30) and the third light modulator (50), the light receiving direction of the third light modulator (50) corresponds to the light scattering direction of the second light modulator (101), and the third light modulator (50) can receive light in four directions;

the second dimmer (101) comprises a first light-dispersing strip (1012) extending in a first direction and a second light-dispersing strip (1014) extending in a second direction; when the first direction is perpendicular to the second direction, the first direction is the up-down direction of the liquid crystal display device, and the second direction is the left-right direction of the liquid crystal display device, the area occupied by the first light-scattering strip (1012) is larger than the area occupied by the second light-scattering strip (1014), and the first dimmer (30) receives light left and right in a narrow viewing angle mode; or, when the first direction is perpendicular to the second direction, the first direction is a vertical direction of the liquid crystal display device, and the second direction is a horizontal direction of the liquid crystal display device, the area occupied by the first light-scattering strip (1012) is smaller than the area occupied by the second light-scattering strip (1014), and the first dimmer (30) receives light vertically in a narrow viewing angle mode.

2. The lcd apparatus of claim 1, wherein when the third light modulator (50) is configured to emit light in four directions, the third light modulator (50) comprises a first light modulation bar (502) and a second light modulation bar (504), the first light modulation bar (502) extends in a direction perpendicular to the second light modulation bar (504), the first light modulation bar (502) extends in a direction parallel to the left-right direction of the lcd apparatus, and the second light modulation bar (504) extends in a direction parallel to the up-down direction of the lcd apparatus.

3. The lcd device of claim 1, wherein the display panel (10) is disposed between the first light modulator (30) and the backlight module (40); or, the first light modulator (30) is arranged between the display panel (10) and the backlight module (40); alternatively, the second dimmer (101) is provided on the display panel (10) and/or the first dimmer (30).

4. The lcd device of claim 1, further comprising a first polarizer (60), a second polarizer (70), and a third polarizer (80), wherein the first polarizer (60) is located at a light incident side of the lcd device, the third polarizer (80) is located at a light emergent side of the lcd device, and the second polarizer (70) is located between the first dimmer (30) and the display panel (10);

the transmission axis directions of the polarizing plates on both sides of the display panel (10) are perpendicular to each other, and the transmission axis directions of the polarizing plates on both sides of the first light modulator (30) are parallel to each other.

5. The liquid crystal display device according to claim 4, wherein the second polarizing plate (70) comprises an antiglare film and a brightness enhancement film stacked, and a bright surface of the brightness enhancement film is disposed toward and away from the backlight module (40); alternatively, the second polarizing plate (70) is an anti-glare polarizing plate.

6. A driving method of a liquid crystal display device according to any one of claims 1 to 5, comprising:

when the liquid crystal display device is in a wide viewing angle display mode, a first voltage of 0V is applied to the second electrode (306), a second voltage is applied to the first electrode (303), the waveform of the second voltage is a pulse wave, and the waveform of the second voltage is as follows: the picture refreshing cycle of the liquid crystal display device is 2t, the voltage value of the second voltage in a time period of t1 is A, and the voltage value in a time period of t2 is-A, wherein t1 is t2 (1/3-1/2) t, and A is 2V-4V;

when the liquid crystal display device is in a narrow viewing angle display mode, a voltage of 0V is applied to the second electrode (306), an alternating voltage is applied to the first electrode (303), and the brightness of the backlight module (40) is controlled to be lower than that in a wide viewing angle display mode.