CN109324449B - Liquid crystal display device and driving method thereof - Google Patents
Liquid crystal display device and driving method thereof Download PDFInfo
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- CN109324449B CN109324449B CN201811361964.3A CN201811361964A CN109324449B CN 109324449 B CN109324449 B CN 109324449B CN 201811361964 A CN201811361964 A CN 201811361964A CN 109324449 B CN109324449 B CN 109324449B
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- G—PHYSICS
- G02—OPTICS
- G02F—OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
- G02F1/00—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics
- G02F1/01—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour
- G02F1/13—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour based on liquid crystals, e.g. single liquid crystal display cells
- G02F1/133—Constructional arrangements; Operation of liquid crystal cells; Circuit arrangements
- G02F1/1333—Constructional arrangements; Manufacturing methods
- G02F1/1343—Electrodes
- G02F1/134309—Electrodes characterised by their geometrical arrangement
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- G—PHYSICS
- G02—OPTICS
- G02F—OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
- G02F1/00—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics
- G02F1/01—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour
- G02F1/13—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour based on liquid crystals, e.g. single liquid crystal display cells
- G02F1/1323—Arrangements for providing a switchable viewing angle
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- G—PHYSICS
- G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
- G09G—ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
- G09G3/00—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes
- G09G3/20—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters
- G09G3/34—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters by control of light from an independent source
- G09G3/36—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters by control of light from an independent source using liquid crystals
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Abstract
The invention discloses a liquid crystal display device and a driving method, the liquid crystal display device comprises a color film substrate, an array substrate and a liquid crystal layer positioned between the color film substrate and the array substrate, a visual angle control electrode is arranged on the color film substrate, the array substrate comprises a plurality of pixel units, a pixel electrode is arranged in each pixel unit, a first common electrode is arranged on the array substrate, the pixel electrode and the first common electrode are respectively positioned at the upper side and the lower side of an insulating layer, a plurality of insulating convex ridges are formed on the insulating layer, a second common electrode is also arranged on the array substrate, the second common electrode and the pixel electrode are in a comb-shaped structure with slits in each pixel unit, electrode strips of the second common electrode and electrode strips of the pixel electrodes are alternately arranged, the electrode strips of the second common electrode are respectively arranged on the insulating convex ridges, and the electrode strips of the second common electrode protrude above the electrode strips of the pixel electrodes, and enabling the electrode strips of the second common electrode to be closer to the color film substrate than the electrode strips of the pixel electrodes.
Description
Technical Field
The present invention relates to the field of liquid crystal display technologies, and in particular, to a liquid crystal display device and a driving method thereof.
Background
Liquid Crystal Displays (LCDs) have the advantages of good picture quality, small size, light weight, low driving voltage, low power consumption, no radiation and relatively low manufacturing cost, and are dominant in the field of flat panel displays.
With the continuous progress of the liquid crystal display technology, the viewing angle of the display has been widened from about 120 ° to over 160 °, and people want to effectively protect business confidentiality and personal privacy while enjoying visual experience brought by a large viewing angle, so as to avoid business loss or embarrassment caused by the leakage of screen information. There is therefore a need for displays that can be switched to narrow viewing angles in addition to wide viewing angles.
An FFS (Fringe Field Switching) mode is a commonly used liquid crystal display mode. Recently, it has been proposed to apply a vertical electric field to liquid crystal molecules by using a viewing angle control electrode on the color filter substrate (CF) side to realize wide and narrow viewing angle switching. Referring to fig. 1 and 2, the lcd device includes an upper substrate 11, a lower substrate 12, and a liquid crystal layer 13 disposed between the upper substrate 11 and the lower substrate 12, wherein a viewing angle control electrode 111 is disposed on the upper substrate 11. As shown in fig. 1, in the wide viewing angle display, the viewing angle control electrode 111 on the upper substrate 11 does not apply a voltage, and the liquid crystal display device realizes the wide viewing angle display. As shown in fig. 2, when a narrow viewing angle display is required, the viewing angle control electrode 111 on the upper substrate 11 is biased, the liquid crystal molecules in the liquid crystal layer 13 tilt due to the vertical electric fields E1, E2, and E3 (as shown by arrows in fig. 2), and the contrast of the liquid crystal display device is reduced due to light leakage, thereby finally realizing the narrow viewing angle display.
However, in practice, when the narrow viewing angle display is performed, there is a certain difference between the electric field E1 and the electric field E2 (the reason for this difference is many, for example, the common electrode 121 is covered by the insulating layer 122, so that the electric field E1 formed between the common electrode 121 and the viewing angle control electrode 111 is weak), which causes the electric field E3 formed at the edge of the pixel electrode 123 to be not perpendicular to the upper substrate 11 and the lower substrate 12, but to be an oblique electric field, and the oblique electric field has a certain component in the horizontal direction, so that the liquid crystal molecules at the edge of the pixel electrode 123 will deflect in the horizontal direction, causing the narrow viewing angle dark state light leakage, and at this time, when the liquid crystal display device is in the dark state, the transmittance of light will increase, and the contrast ratio will decrease.
Disclosure of Invention
In order to overcome the disadvantages and shortcomings of the prior art, an object of the present invention is to provide a liquid crystal display device and a driving method thereof, so as to solve the problems of light leakage in a dark state with a narrow viewing angle and reduced contrast.
The purpose of the invention is realized by the following technical scheme:
the invention provides a liquid crystal display device, comprising a color film substrate, an array substrate arranged opposite to the color film substrate and a liquid crystal layer positioned between the color film substrate and the array substrate, wherein the color film substrate is provided with a visual angle control electrode for controlling the switching of wide and narrow visual angles, the array substrate comprises a plurality of pixel units formed by mutually insulating, crossing and limiting a plurality of scanning lines and a plurality of data lines, each pixel unit is internally provided with a pixel electrode, the array substrate is provided with a first common electrode, the pixel electrode and the first common electrode are positioned on different layers and are insulated and isolated through an insulating layer, the pixel electrode and the first common electrode are respectively positioned on the upper side and the lower side of the insulating layer, a plurality of insulating convex ridges are formed on the insulating layer, the array substrate is also provided with a second common electrode, and the second common electrode and the pixel electrode are both in a comb-shaped structure with a slit in each pixel unit, the electrode strips of the second common electrode and the electrode strips of the pixel electrode are arranged alternately, the electrode strips of the second common electrode are respectively arranged on the plurality of insulating ridges, and the electrode strips of the second common electrode protrude above the electrode strips of the pixel electrode, so that the electrode strips of the second common electrode are closer to the color film substrate than the electrode strips of the pixel electrode.
Further, the electrode strips of the pixel electrode, the electrode strips of the second common electrode and the insulating ridges are the same in shape and are all in a "<" shape or a ">" shape.
Further, the electrode stripes of the second common electrode are disconnected at the bent portions of the "<" -shaped or ">" shaped structures.
Furthermore, the insulating layer and the plurality of insulating ridges are formed by etching and patterning an insulating layer film, wherein the upper half portion of the insulating layer film is etched and patterned to form the plurality of insulating ridges, the lower half portion of the insulating layer film is not etched to form the insulating layer, and the insulating layer is of a full-face structure.
Further, the first common electrode is formed by the entire surface of the first conductive layer film, and the pixel electrode and the second common electrode are formed by etching and patterning the second conductive layer film.
Furthermore, the insulating layer is formed by a first insulating layer film on the whole surface, and a plurality of insulating ridges are formed by etching and patterning a second insulating layer film.
Further, the first common electrode is formed by etching and patterning the entire first conductive layer film, the pixel electrode is formed by etching and patterning the second conductive layer film, and the second common electrode is formed by etching and patterning the third conductive layer film.
The present invention also provides a driving method of a liquid crystal display device for driving the liquid crystal display device as described above, the driving method comprising:
in a first viewing angle mode, applying a direct current common voltage to the first common electrode and the second common electrode, and applying a first voltage to the viewing angle control electrode, so that a voltage difference between the viewing angle control electrode and the first common electrode and a voltage difference between the viewing angle control electrode and the second common electrode are both smaller than a preset value;
in a second viewing angle mode, a dc common voltage is applied to both the first common electrode and the second common electrode, and a second voltage is applied to the viewing angle control electrode, so that a voltage difference between the viewing angle control electrode and the first common electrode and a voltage difference between the viewing angle control electrode and the second common electrode are both greater than a preset value.
Further, in the first viewing angle mode, the potential of the first voltage is the same as the potential of the dc common voltage; in a second view angle mode, the second voltage is an ac voltage that is biased up and down with respect to the dc common voltage.
Further, the liquid crystal layer adopts positive liquid crystal molecules, the first visual angle mode is a wide visual angle mode, and the second visual angle mode is a narrow visual angle mode; alternatively, the liquid crystal layer uses negative liquid crystal molecules, the first viewing angle mode is a narrow viewing angle mode, and the second viewing angle mode is a wide viewing angle mode.
The invention has the beneficial effects that: a plurality of insulating convex ridges are formed on the insulating layer, a second common electrode is arranged on the array substrate, the second common electrode and the pixel electrode are both of a comb-shaped structure with slits in each pixel unit, electrode strips of the second common electrode and electrode strips of the pixel electrode are arranged alternately, the electrode strips of the second common electrode are arranged on the insulating convex ridges respectively, and the electrode strips of the second common electrode protrude above the electrode strips of the pixel electrode, so that the electrode strips of the second common electrode are closer to the color film substrate than the electrode strips of the pixel electrode. When the liquid crystal display device displays at a narrow visual angle, a uniform vertical electric field is formed between the color film substrate and the array substrate, so that light leakage of a dark state at the narrow visual angle is prevented, the contrast is improved, and the display image quality of the liquid crystal display device is enhanced.
Drawings
FIG. 1 is a schematic cross-sectional view of a prior art LCD device at a wide viewing angle;
FIG. 2 is a schematic cross-sectional view of a prior art LCD device at a narrow viewing angle;
FIG. 3 is a schematic diagram of a single pixel unit according to an embodiment of the present invention;
FIG. 4 is a schematic cross-sectional view taken along A-A in FIG. 3 of a liquid crystal display device with a wide viewing angle according to one embodiment of the present invention;
FIG. 5 is a schematic cross-sectional view taken along A-A in FIG. 3 of a liquid crystal display device with a narrow viewing angle according to one embodiment of the present invention;
FIGS. 6a-6f are flow charts illustrating the fabrication of an array substrate according to one embodiment of the present invention;
FIG. 7 is a waveform diagram of a driving voltage for driving a liquid crystal display device in accordance with the present invention;
FIG. 8 is a schematic diagram of a single pixel unit according to a second embodiment of the present invention;
FIG. 9 is a schematic diagram of a planar structure of a single pixel unit in the third embodiment of the present invention;
FIG. 10 is a schematic cross-sectional view taken along line B-B in FIG. 8 of a second example of the LCD device according to the present invention;
FIG. 11 is a schematic cross-sectional view taken along line B-B in FIG. 8 of a second example of the LCD device according to the present invention at a narrow viewing angle;
FIGS. 12a-12i are flow charts illustrating the fabrication of an array substrate according to a second embodiment of the present invention;
fig. 13 is a schematic cross-sectional view of a liquid crystal display device of a fourth embodiment of the present invention, which uses negative liquid crystal at a narrow viewing angle;
fig. 14 is a schematic cross-sectional view of a liquid crystal display device of a fourth embodiment of the present invention, which employs negative liquid crystal at a wide viewing angle;
FIG. 15 is a schematic plan view of a liquid crystal display device according to the present invention;
FIG. 16 is a second schematic plan view of the liquid crystal display device of the present invention.
Detailed Description
To further illustrate the technical means and effects of the present invention adopted to achieve the predetermined objects, the following detailed description of the embodiments, structures, features and effects of the liquid crystal display device and the driving method thereof according to the present invention with reference to the accompanying drawings and preferred embodiments is as follows:
[ example one ]
As shown in fig. 3 to fig. 5, a liquid crystal display device according to a first embodiment of the present invention includes a color filter substrate 20, an array substrate 30 disposed opposite to the color filter substrate 20, and a liquid crystal layer 40 disposed between the color filter substrate 20 and the array substrate 30. The liquid crystal layer 40 is made of positive liquid crystal molecules (the dielectric anisotropy is positive liquid crystal molecules), a small initial pretilt angle can be formed between the positive liquid crystal molecules in the liquid crystal layer 40 and the color film substrate 20 and the array substrate 30, and the range of the initial pretilt angle can be less than or equal to 10 degrees, that is: 0 DEG < theta < 10 DEG to reduce the response time of vertical deflection of the positive liquid crystal molecules.
On the color filter substrate 20, a color resist layer 22, a Black Matrix (BM)21, a planarization layer 23, and a viewing angle control electrode 24 for controlling switching of a wide and narrow viewing angle are provided on a side facing the liquid crystal layer 30. The color resist layer 22 includes, for example, color resist materials of three colors of red (R), green (G), and blue (B), and pixel units P of the three colors of red, green, and blue are formed correspondingly. The black matrix 21 is positioned between the pixel units P of three colors of red, green, and blue, so that adjacent pixel units P are spaced apart from each other by the black matrix 21.
The array substrate 30 is provided with a plurality of scan lines 31 and a plurality of data lines 32 which are insulated and crossed with each other on one side facing the liquid crystal layer 30, a plurality of pixel units P are defined by the plurality of scan lines 31 and the plurality of data lines 32 which are crossed with each other, a pixel electrode 37 and a thin film transistor 33 are arranged in each pixel unit P, and the thin film transistor 33 connects the scan lines 31 and the data lines 32 of the pixel electrode 37 and the pixel electrode 37. The array substrate 30 is further provided with a first common electrode 35 which covers the whole surface, the pixel electrode 37 and the first common electrode 35 are located at different layers and insulated and isolated through an insulating layer 36, the pixel electrode 37 is located on the upper side of the insulating layer 36, and the first common electrode 35 is located on the lower side of the insulating layer 36. A plurality of insulating ridges 361 are formed on the insulating layer 36. The array substrate 30 is further provided with a second common electrode 38, the second common electrode 38 and the pixel electrode 37 are both of a comb-like structure having a slit in each pixel unit P, and electrode stripes of the second common electrode 38 and electrode stripes of the pixel electrode 37 are alternately arranged, the electrode stripes of the second common electrode 38 are respectively disposed on the plurality of insulating ridges 361, and the electrode stripes of the second common electrode 38 protrude above the electrode stripes of the pixel electrode 37, so that the electrode stripes of the second common electrode 38 are closer to the color filter substrate 20 than the electrode stripes of the pixel electrode 37.
In this embodiment, the array substrate 30 and the color filter substrate 20 may be made of glass, acrylic, polycarbonate, or other materials. The first common electrode 35, the second common electrode 38, the pixel electrode 37, and the viewing angle controlling electrode 24 may be made of a transparent conductive material such as Indium Tin Oxide (ITO), Indium Zinc Oxide (IZO), or the like.
Further, the shapes of the electrode strip of the pixel electrode 37, the electrode strip of the second common electrode 38, and the plurality of insulating ridges 361 are the same and are all "<" or ">", and in this embodiment, the shapes of the electrode strip of the pixel electrode 37, the electrode strip of the second common electrode 38, and the plurality of insulating ridges 361 are the same and are all "<" shaped.
In this embodiment, a plurality of metal electrodes (for example, disposed in the black matrix 21 shielding region) may be further disposed on the first common electrode 35 and the second common electrode 38, respectively, so as to reduce the resistance of the first common electrode 35 and the second common electrode 38. The first common electrode 35 and the second common electrode 38 may be connected together by punching a hole in the insulating layer 36 of the non-display area and applying the same common signal.
In this embodiment, the insulating layer 36 and the plurality of insulating ridges 361 are formed by etching and patterning an insulating layer film J, wherein the upper half portion of the insulating layer film J is etched and patterned to form the plurality of insulating ridges 361, the lower half portion of the insulating layer film J is not etched to form the insulating layer 36, and the insulating layer 36 is a full-surface structure;
further, the first common electrode 35 is formed of the entire surface of the first conductive layer film T1, and the pixel electrode 37 and the second common electrode 38 are formed of the second conductive layer film T2 by etching patterning. Specifically, the method comprises the following steps:
as shown in fig. 6a, a planarization layer 34 is formed over the substrate on which the scan lines 31, the data lines 32, and the thin film transistors 33 are formed. As for the steps of fabricating the scan lines 31, the data lines 32 and the tfts 33, please refer to the prior art, which is not described herein;
as shown in fig. 6b, the entire first conductive layer thin film T1 is deposited on the planarization layer 34 and the first common electrode 35 is formed;
as shown in fig. 6c and 6d, an insulating film J is covered on the first common electrode 35, and the insulating film J is etched and patterned once by using the first mask, wherein the upper half of the insulating film J is etched and patterned to form a plurality of insulating ridges 361, the lower half of the insulating film J is not etched to form an insulating layer 36, and the insulating layer 36 is a full-surface structure.
As shown in fig. 6e and 6f, a second conductive layer film T2 is deposited on the insulating layer 36 and the plurality of insulating ridges 361, and the second conductive layer film T2 is etched once and patterned using a second mask to form the pixel electrode 37 and the second common electrode 38, wherein the electrode stripes of the second common electrode 38 are on the plurality of insulating ridges 361, respectively.
The present embodiment further provides a driving method of a liquid crystal display device, the driving method is used for driving the liquid crystal display device as described above to switch the liquid crystal display device between a wide viewing angle mode and a narrow viewing angle mode, and the driving method includes:
as shown in fig. 7, in the wide viewing angle mode, a dc common voltage Vcom is applied to both the first common electrode 35 and the second common electrode 38 on the array substrate 30, and a first voltage V1 is applied to the viewing angle control electrode 24 on the color filter substrate 20, so that both a voltage difference between the viewing angle control electrode 24 and the first common electrode 35 and a voltage difference between the viewing angle control electrode 24 and the second common electrode 38 are smaller than a predetermined value (for example, smaller than 0.5V), in this embodiment, a potential of the first voltage V1 is the same as a potential of the dc common voltage Vcom;
at this time, since the voltage difference between the viewing angle control electrode 24 and the first common electrode 35 and the voltage difference between the viewing angle control electrode 24 and the second common electrode 38 are both small, the tilt angle of the positive liquid crystal molecules in the liquid crystal layer 40 hardly changes, and the liquid crystal display device still maintains the lying posture, so that the liquid crystal display device displays normal wide viewing angle, as shown in fig. 4.
In the narrow viewing angle mode, a dc common voltage Vcom is applied to both the first common electrode 35 and the second common electrode 38 on the array substrate 30, and a second voltage V2 is applied to the viewing angle control electrode 24 on the color film substrate 20, so that a voltage difference between the viewing angle control electrode 24 and the first common electrode 35 and a voltage difference between the viewing angle control electrode 24 and the second common electrode 38 are both greater than a preset value (for example, greater than 3V), in this embodiment, the second voltage V2 is an ac voltage that is offset up and down relative to the dc common voltage Vcom;
at this time, since the voltage difference between the viewing angle control electrode 24 and the first common electrode 35 and the voltage difference between the viewing angle control electrode 24 and the second common electrode 38 are both large, a strong vertical electric field E (as shown by an arrow in fig. 5) is generated between the array substrate 30 and the color film substrate 20, and the positive liquid crystal molecules rotate in a direction parallel to the electric field lines under the action of the electric field, so that the positive liquid crystal molecules are deflected under the action of the vertical electric field E, so that the tilt angle between the positive liquid crystal molecules and the array substrate 30 and the color film substrate 20 is increased and tilted, the positive liquid crystal molecules are changed from the flat posture to the inclined posture, so that the liquid crystal display device has large-angle observation light leakage, the contrast is reduced in the oblique direction and the viewing angle is narrowed, and the liquid crystal display device finally realizes narrow-viewing-angle display, as.
The liquid crystal display device with the framework can ensure that the electric field between the array substrate 30 and the color film substrate 20 keeps a vertical state and is uniformly distributed, so that light leakage of the liquid crystal display device in a narrow-viewing-angle dark state is reduced, the contrast of the liquid crystal display device is improved, and the display image quality is enhanced.
The following is a simulation table of the liquid crystal display device of the present invention and the prior art:
in table 1, in the dark state with a narrow viewing angle, the transmittance of light in the prior art is 0.033%, the transmittance of light in the present invention is 0.007%, and the transmittance of light is reduced by 79%, i.e., the brightness is darker; in a narrow-viewing-angle bright state, the transmittance of light in the prior art is 1.400%, the transmittance of light in the invention is 1.560%, and the transmittance of light is increased by 11%, namely the brightness is brighter; the contrast ratio is improved by 424% when the narrow viewing angle is displayed. Therefore, the liquid crystal display device effectively prevents light leakage in a narrow viewing angle dark state, greatly improves the contrast of the liquid crystal display device and enhances the display image quality;
in table 2, in the dark state with wide viewing angle, the transmittance of light in the prior art is 0.003%, the transmittance of light in the present invention is 0.00304%, and the transmittance of light is increased by 1.3%, i.e., the brightness is brighter; in a wide-viewing-angle bright state, the transmittance of light in the prior art is 2.886%, the transmittance of light in the invention is 2.993%, and the transmittance of light is increased by 3.7%, namely the brightness is brighter; when the display is displayed at a wide viewing angle, the contrast ratio is improved by 2.4 percent. Therefore, the liquid crystal display device of the invention also effectively improves the contrast ratio in the wide viewing angle mode and enhances the display image quality.
[ example two ]
As shown in fig. 8, 10 and 11, a liquid crystal display device according to a second embodiment of the present invention is substantially the same as the liquid crystal display device according to the first embodiment (fig. 3, 4 and 5), except that:
in the present embodiment, the insulating layer 36 is formed of the entire first insulating layer film J1, and the plurality of insulating ridges 361 are formed of the second insulating layer film J2 by etching and patterning.
Further, the first common electrode 35 is formed by the entire surface of the first conductive layer film T1, the pixel electrode 37 is formed by the second conductive layer film T2 through etching patterning, and the second common electrode 38 is formed by the third conductive layer film T3 through etching patterning. Specifically, the method comprises the following steps:
as shown in fig. 12a, a planarization layer 34 is coated on the substrate on which the scan lines 31, the data lines 32, and the thin film transistors 33 are formed. As for the steps of fabricating the scan lines 31, the data lines 32 and the tfts 33, please refer to the prior art, which is not described herein;
as shown in fig. 12b, the entire first conductive layer thin film T1 is deposited on the planarization layer 34 and the first common electrode 35 is formed;
as shown in fig. 12c, a first insulating layer film J1 is covered on the first common electrode 35 and the insulating layer 36 is formed over the entire surface;
as shown in fig. 12d and 12e, a second conductive layer thin film T2 is deposited on the insulating layer 36, and the second conductive layer thin film T2 is etched once and patterned using a first mask to form a pixel electrode 37 having a slit;
as shown in fig. 12f to 12h, the second insulating layer film J2 is covered on the insulating layer 36 and the pixel electrode 37, the third conductive layer film T3 is deposited on the second insulating layer film J2, the third conductive layer film T3 is etched once and patterned by using the second mask to form the second common electrode 38 having slits, and the electrode stripes of the second common electrode 38 and the electrode stripes of the pixel electrode 37 are alternately arranged;
as shown in fig. 12i, the second insulating film J2 is then etched once and patterned using a third mask or using the second common electrode 38 as a mask, to remove the other regions covered by the second common electrode 38 and form a plurality of insulating ridges 361.
It should be understood by those skilled in the art that the rest of the structure and the operation principle of the present embodiment are the same as those of the first embodiment, and are not described herein again.
[ third example ]
As shown in fig. 9, a liquid crystal display device according to a third embodiment of the present invention is substantially the same as the liquid crystal display device according to the second embodiment (fig. 8), except that in this embodiment, the electrode strips of the second common electrode 38 are broken at the bent portion of the "<" -shaped structure, so that the second common electrode 38 is divided into an upper portion and a lower portion in the pixel unit P.
It should be understood by those skilled in the art that the rest of the structure and the operation principle of the present embodiment are the same as those of the present embodiment, and are not described herein again.
[ example four ]
As shown in fig. 13 and 14, a liquid crystal display device according to a fourth embodiment of the present invention is substantially the same as the liquid crystal display device according to the first embodiment (fig. 4 and 5), except that negative liquid crystal molecules (liquid crystal molecules having negative dielectric anisotropy) are used as the liquid crystal layer 40 in this embodiment. With the technical progress, the performance of the negative liquid crystal is remarkably improved, and the application is more and more extensive. In this embodiment, as shown in fig. 13, in an initial state (i.e., under a condition that no voltage is applied to the liquid crystal display device), the negative liquid crystal molecules in the liquid crystal layer 40 have a larger initial pretilt angle relative to the array substrate 30 and the color filter substrate 20, that is, the negative liquid crystal molecules are in an inclined posture relative to the array substrate 30 and the color filter substrate 20 in the initial state.
Specifically, referring to fig. 7, in the narrow viewing angle mode, a dc common voltage Vcom is applied to the first common electrode 35 and the second common electrode 38 on the array substrate 30, and a first voltage V1 is applied to the viewing angle control electrode 24 on the color film substrate 20, so that a voltage difference between the viewing angle control electrode 24 and the first common electrode 35 and a voltage difference between the viewing angle control electrode 24 and the second common electrode 38 are both smaller than a preset value (for example, smaller than 0.5V), in this embodiment, a potential of the first voltage V1 is the same as a potential of the dc common voltage Vcom;
at this time, since the voltage difference between the viewing angle control electrode 24 and the first common electrode 35 and the voltage difference between the viewing angle control electrode 24 and the second common electrode 38 are both small, the tilt angle of the positive liquid crystal molecules in the liquid crystal layer 40 hardly changes, and the positive liquid crystal molecules are in an inclined posture with respect to the array substrate 30 and the color film substrate 20, so that the liquid crystal display device has large-angle observation light leakage, the contrast is reduced in the oblique direction, the viewing angle is narrowed, and the liquid crystal display device displays in a normal narrow viewing angle, as shown in fig. 13.
In the wide viewing angle mode, a dc common voltage Vcom is applied to both the first common electrode 35 and the second common electrode 38 on the array substrate 30, and a second voltage V2 is applied to the viewing angle control electrode 24 on the color film substrate 20, so that a voltage difference between the viewing angle control electrode 24 and the first common electrode 35 and a voltage difference between the viewing angle control electrode 24 and the second common electrode 38 are both greater than a preset value (for example, greater than 3V), in this embodiment, the second voltage V2 is an ac voltage that is offset up and down relative to the dc common voltage Vcom;
at this time, since the voltage difference between the viewing angle control electrode 24 and the first common electrode 35 and the voltage difference between the viewing angle control electrode 24 and the second common electrode 38 are both large, a strong vertical electric field E (as shown by an arrow in fig. 14) is generated between the array substrate 30 and the color film substrate 20, and negative liquid crystal molecules rotate in a direction perpendicular to electric field lines under the action of the electric field, so that the negative liquid crystal molecules are deflected under the action of the vertical electric field E, so that the tilt angle between the negative liquid crystal molecules and the array substrate 30 and the color film substrate 20 is reduced, and the negative liquid crystal molecules are changed from the tilted posture to the lying posture, so that the liquid crystal display device finally realizes wide viewing angle display, as shown in fig. 14.
It should be understood by those skilled in the art that the rest of the structure and the operation principle of the present embodiment are the same as those of the first embodiment, and are not described herein again.
Fig. 15 and 16 are schematic plan views illustrating a liquid crystal display device according to the present invention, and referring to fig. 15 and 16, the liquid crystal display device is provided with a viewing angle switching key 50 for a user to send a viewing angle switching request to the liquid crystal display device. The view switching key 50 may be a physical key (as shown in fig. 15), or may be a software control or application program (APP) to implement a switching function (as shown in fig. 16, a wide view and a narrow view are set by a slider). When a user needs to switch between a wide viewing angle and a narrow viewing angle, a viewing angle switching request can be sent to the liquid crystal display device by operating the viewing angle switching key 50, and finally the driving chip 60 controls the voltage applied to the viewing angle control electrode 24, to control the voltage difference between the viewing angle control electrode 24 and the first common electrode 35 and the voltage difference between the viewing angle control electrode 24 and the second common electrode 38, the liquid crystal display device can realize the switching between a wide visual angle and a narrow visual angle, when the wide visual angle is switched, the driving method adopts the driving method corresponding to the wide angle mode, when the narrow angle mode is switched, the driving method adopts the driving method corresponding to the narrow angle mode, therefore, the liquid crystal display device has strong operation flexibility and convenience, and achieves the multifunctional liquid crystal display device integrating entertainment video and privacy.
The terms "forming" and "fabricating" as used herein should be understood to include the broad understanding that physical vapor deposition, chemical vapor deposition, molecular beam epitaxy, etc. may be used in a manner commonly used in the art. Since there are various ways of forming the thin film, the process method of forming each thin film is not specifically described herein because it is not the point of the present invention.
In the present invention, the directional terms such as upper, lower, left, right, front and rear, etc. are defined by the positions of the structures in the drawings and the positions of the structures relative to each other, and are only used for the sake of clarity and convenience in technical solution. It is to be understood that the use of the directional terms should not be taken to limit the scope of the claims.
Although the present invention has been described with reference to the preferred embodiments, it should be understood that various changes, substitutions and alterations can be made herein without departing from the spirit and scope of the invention as defined by the appended claims.
Claims (10)
1. A liquid crystal display device comprises a color film substrate (20), an array substrate (30) arranged opposite to the color film substrate (20) and a liquid crystal layer (40) arranged between the color film substrate (20) and the array substrate (30), wherein a view angle control electrode (24) used for controlling wide and narrow view angle switching is arranged on the color film substrate (20), the array substrate (30) comprises a plurality of pixel units (P) formed by mutually insulating and intersecting a plurality of scanning lines (31) and a plurality of data lines (32), a pixel electrode (37) is arranged in each pixel unit (P), a first common electrode (35) is arranged on the array substrate (30), the pixel electrode (37) and the first common electrode (35) are positioned on different layers and are insulated and isolated through an insulating layer (36), and the pixel electrode (37) and the first common electrode (35) are respectively positioned on the upper side and the lower side of the insulating layer (36), the liquid crystal display panel is characterized in that a plurality of insulating ridges (361) are formed on the insulating layer (36), a second common electrode (38) is further disposed on the array substrate (30), the second common electrode (38) and the pixel electrode (37) are both of a comb-shaped structure with slits in each pixel unit (P), electrode stripes of the second common electrode (38) and electrode stripes of the pixel electrode (37) are alternately arranged, the electrode stripes of the second common electrode (38) are respectively disposed on the insulating ridges (361), and the electrode stripes of the second common electrode (38) protrude above the electrode stripes of the pixel electrode (37), so that the electrode stripes of the second common electrode (38) are closer to the color film substrate (20) than the electrode stripes of the pixel electrode (37).
2. The lcd device of claim 1, wherein the electrode stripes of the pixel electrodes (37), the electrode stripes of the second common electrode (38), and the insulating ridges (361) have the same shape and are all "<" or ">".
3. A liquid crystal display device as claimed in claim 2, characterized in that the electrode strips of the second common electrode (38) are interrupted at the bend portions of the "<" or ">" shaped structure.
4. The lcd device of claim 1, wherein the insulating layer (36) and the insulating ridges (361) are formed by etching and patterning an insulating film (J), wherein an upper portion of the insulating film (J) is etched and patterned to form the insulating ridges (361), a lower portion of the insulating film (J) is not etched to form the insulating layer (36), and the insulating layer (36) has a full-face structure.
5. The liquid crystal display device according to claim 4, wherein the first common electrode (35) is formed by a full-surface first conductive layer film (T1), and the pixel electrode (37) and the second common electrode (38) are formed by etching and patterning a second conductive layer film (T2).
6. The liquid crystal display device of claim 1, wherein the insulating layer (36) is formed of a full-face first insulating layer film (J1), and the plurality of insulating ridges (361) are formed of a second insulating layer film (J2) by etching patterning.
7. The liquid crystal display device according to claim 6, wherein the first common electrode (35) is formed by etching and patterning the entire surface of the first conductive layer film (T1), the pixel electrode (37) is formed by etching and patterning the second conductive layer film (T2), and the second common electrode (38) is formed by etching and patterning the third conductive layer film (T3).
8. A driving method of a liquid crystal display device, the driving method being for driving the liquid crystal display device according to any one of claims 1 to 7, the driving method comprising:
in a first viewing angle mode, applying a direct current common voltage (Vcom) to the first common electrode (35) and the second common electrode (38), and applying a first voltage (V1) to the viewing angle control electrode (24) to make a voltage difference between the viewing angle control electrode (24) and the first common electrode (35) and a voltage difference between the viewing angle control electrode (24) and the second common electrode (38) smaller than a preset value;
in a second viewing angle mode, a dc common voltage (Vcom) is applied to both the first common electrode (35) and the second common electrode (38), and a second voltage (V2) is applied to the viewing angle control electrode (24), so that a voltage difference between the viewing angle control electrode (24) and the first common electrode (35) and a voltage difference between the viewing angle control electrode (24) and the second common electrode (38) are both greater than preset values.
9. The method according to claim 8, wherein the first voltage (V1) has the same potential as the dc common voltage (Vcom) in the first viewing angle mode; in a second viewing angle mode, the second voltage (V2) is an ac voltage that is biased up and down with respect to the dc common voltage (Vcom).
10. The method of claim 8, wherein the liquid crystal layer (40) employs positive liquid crystal molecules, the first viewing angle mode is a wide viewing angle mode, and the second viewing angle mode is a narrow viewing angle mode; alternatively, the liquid crystal layer (40) uses negative liquid crystal molecules, and the first viewing angle mode is a narrow viewing angle mode and the second viewing angle mode is a wide viewing angle mode.
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| CN110031990A (en) * | 2019-02-15 | 2019-07-19 | 昆山龙腾光电有限公司 | Liquid crystal display device and its driving method |
| CN109856869B (en) * | 2019-03-26 | 2021-09-21 | 昆山龙腾光电股份有限公司 | Array substrate and manufacturing method thereof, liquid crystal display device and driving method |
| CN112394558B (en) * | 2019-08-14 | 2023-08-08 | 中强光电股份有限公司 | Electric control visual angle switcher and display device |
| CN110673406B (en) * | 2019-09-17 | 2022-07-01 | 昆山龙腾光电股份有限公司 | Liquid crystal display panel with switchable viewing angle and driving method thereof |
| CN110673407B (en) * | 2019-10-11 | 2022-04-22 | 昆山龙腾光电股份有限公司 | Liquid crystal display device having a plurality of pixel electrodes |
| CN112162425B (en) * | 2020-10-29 | 2023-12-01 | 京东方科技集团股份有限公司 | Pixel unit, driving method thereof, array substrate and vertical alignment type display device |
Citations (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102213874A (en) * | 2010-04-06 | 2011-10-12 | 索尼公司 | Liquid crystal display and method for manufacturing liquid crystal display |
| CN103926733A (en) * | 2014-04-10 | 2014-07-16 | 昆山龙腾光电有限公司 | Liquid crystal display device |
| CN105116639A (en) * | 2015-09-17 | 2015-12-02 | 武汉华星光电技术有限公司 | Blue-phase liquid crystal display and blue-phase liquid crystal display module and manufacturing method thereof |
| CN105824158A (en) * | 2016-05-30 | 2016-08-03 | 京东方科技集团股份有限公司 | Array substrate, display device and array substrate manufacturing method |
| CN106444104A (en) * | 2016-10-10 | 2017-02-22 | 昆山龙腾光电有限公司 | Liquid crystal display device capable of switching visual angle |
| CN106773335A (en) * | 2016-12-30 | 2017-05-31 | 深圳市华星光电技术有限公司 | A kind of liquid crystal display panel |
| CN106932973A (en) * | 2017-04-18 | 2017-07-07 | 昆山龙腾光电有限公司 | The changeable liquid crystal display device in visual angle |
| CN107229163A (en) * | 2017-06-28 | 2017-10-03 | 昆山龙腾光电有限公司 | Width visual angle changeable liquid crystal display device and driving method |
| CN107656407A (en) * | 2017-09-28 | 2018-02-02 | 京东方科技集团股份有限公司 | Array base palte and its manufacture method, display device |
| CN207249281U (en) * | 2017-09-25 | 2018-04-17 | 昆山龙腾光电有限公司 | The changeable liquid crystal display device in visual angle |
| CN108508666A (en) * | 2018-04-13 | 2018-09-07 | 昆山龙腾光电有限公司 | Array substrate, liquid crystal display device and view angle switch method |
| CN208044266U (en) * | 2018-03-12 | 2018-11-02 | 昆山龙腾光电有限公司 | Liquid crystal display device |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR100709709B1 (en) * | 2000-07-27 | 2007-04-19 | 삼성전자주식회사 | A vertically aligned mode liquid crystal display |
-
2018
- 2018-11-15 CN CN201811361964.3A patent/CN109324449B/en active Active
Patent Citations (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102213874A (en) * | 2010-04-06 | 2011-10-12 | 索尼公司 | Liquid crystal display and method for manufacturing liquid crystal display |
| CN103926733A (en) * | 2014-04-10 | 2014-07-16 | 昆山龙腾光电有限公司 | Liquid crystal display device |
| CN105116639A (en) * | 2015-09-17 | 2015-12-02 | 武汉华星光电技术有限公司 | Blue-phase liquid crystal display and blue-phase liquid crystal display module and manufacturing method thereof |
| CN105824158A (en) * | 2016-05-30 | 2016-08-03 | 京东方科技集团股份有限公司 | Array substrate, display device and array substrate manufacturing method |
| CN106444104A (en) * | 2016-10-10 | 2017-02-22 | 昆山龙腾光电有限公司 | Liquid crystal display device capable of switching visual angle |
| CN106773335A (en) * | 2016-12-30 | 2017-05-31 | 深圳市华星光电技术有限公司 | A kind of liquid crystal display panel |
| CN106932973A (en) * | 2017-04-18 | 2017-07-07 | 昆山龙腾光电有限公司 | The changeable liquid crystal display device in visual angle |
| CN107229163A (en) * | 2017-06-28 | 2017-10-03 | 昆山龙腾光电有限公司 | Width visual angle changeable liquid crystal display device and driving method |
| CN207249281U (en) * | 2017-09-25 | 2018-04-17 | 昆山龙腾光电有限公司 | The changeable liquid crystal display device in visual angle |
| CN107656407A (en) * | 2017-09-28 | 2018-02-02 | 京东方科技集团股份有限公司 | Array base palte and its manufacture method, display device |
| CN208044266U (en) * | 2018-03-12 | 2018-11-02 | 昆山龙腾光电有限公司 | Liquid crystal display device |
| CN108508666A (en) * | 2018-04-13 | 2018-09-07 | 昆山龙腾光电有限公司 | Array substrate, liquid crystal display device and view angle switch method |
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