JP4638891B2 - Transflective LCD - Google Patents

Description

  The present invention relates to a liquid crystal display, and more particularly to a transflective liquid crystal display.

  In order to satisfy demands for thinness, light weight, and low power consumption, liquid crystal displays (LCDs) are widely used in current electrical products such as notebook computers, digital cameras, and projectors. In general, liquid crystal panels are classified into a transmissive type, a reflective type, and a transflective type. A transmissive liquid crystal display uses a backlight module as a light source, a reflective liquid crystal display uses external light as a light source, and a transflective liquid crystal panel uses both the backlight module and external light.

  As shown in FIG. 10, the conventional color liquid crystal panel 1 includes a two-dimensional pixel 10 array. Each pixel 10 has a plurality of subpixels, and usually has three primary colors of red, green, and blue. These red, green, and blue components are displayed by color filters, respectively. FIG. 11 is a plan view showing a pixel structure of a conventional transflective liquid crystal panel. 12a and 12b are cross-sectional views showing the pixel structure. As shown in FIG. 11, one pixel is divided into three subpixels 12R, 12G, and 12B, and each subpixel is further divided into a transmission region (TA) and a reflection region (RA). As shown in FIG. 12a, in the transmissive region, light from the backlight source enters the pixel region through the lower substrate 30, and sequentially passes through the liquid crystal layer, the color filter R, and the upper substrate 20. In the reflection region, light from above the upper substrate 20 sequentially passes through the upper substrate 20, the color filter R, and the liquid crystal layer, and then is reflected by the reflective layer or the reflective electrode 52. Alternatively, as shown in FIG. 12 b, a colorless filter (Non-Color Filter, NCF) corresponding to a part of the reflection region can be formed on the surface of the upper substrate 20.

Further, according to the conventional technique, each pixel includes another layer for controlling the optical characteristics of the liquid crystal layer, for example, the element layer 50 and one or two electrode layers. The transparent electrode 54 provided in the element layer 50 and the common electrode 25 provided in the color filter are elements for controlling the optical characteristics of the liquid crystal layer in the transmissive region, and the reflective electrode 52 and the common electrode 25 are provided in the liquid crystal layer in the reflective region. It is an element that controls optical characteristics. The common electrode 25 is connected to a common line (Common Line). The element layer 50 is generally formed on the lower substrate 30 and includes gate lines 31 and 32, data lines 21-24 (shown in FIG. 11), a plurality of transistors, and a protective layer (not shown). After the gate line signal current flows, a storage capacitor is provided in the element layer 50 in order to store the charge of the sub-pixel. FIG. 13 is an explanatory diagram showing an equivalent circuit diagram of a conventional subpixel (m, n) having a transmissive region and a reflective region. In FIG. 13, the first liquid crystal capacitance C _LC1 is the capacitance of the liquid crystal layer between the transparent electrode 54 and the common electrode 25, and the second liquid crystal capacitance C _LC2 is the liquid crystal layer between the reflective electrode 52 and the common electrode 25. a capacitance, _{C 1} is the storage, COM is common line. In addition, the conventional liquid crystal panel further includes a λ / 4 plate and a polarizer.

  The single gap transflective liquid crystal panel has a drawback that the voltage range in which the transmittance (VT curve) of the transmissive region and the reflectance (VR curve) of the reflective region reach the peak value is different. is there. As shown in FIG. 14, the VR curve has a peak value at a voltage of 2.8V, and the VT curve has a voltage range of 3.7V to 5V as a peak interval. In other words, the reflectance when the transmittance is high is low.

The prior art improves the above problem by utilizing a double gap structure in which the gap in the reflective region is about half the gap in the transmissive region. Although the double gap design is theoretically effective, it is difficult to realize due to the complicated manufacturing process. Other attempts have been proposed, for example, to control the voltage levels in the reflective and transmissive regions or to apply reflective electrodes via a dielectric layer. For example, the capacitance can be used to reduce the voltage level in the reflective region relative to the voltage level in the transmissive region. As shown in FIG. 15, independent capacitance C _C is electrically connected in series to the C _LC2. In this case, the voltage level of the reflective electrode related to the voltage level V _COM1 of the common line can be calculated by the following formula 1. Among them, V _data indicates the voltage level of the data line.
[Formula 1]

As shown in FIG. 16a, by adjusting the ratio C _C / (C _LC2 + C _C ), the peak value of the reflectance curve can be moved in the high voltage direction to match the transmittance curve. Then, the phenomenon of low reflectance accompanying high transmittance can be avoided.

  However, although the transmittance increases rapidly from the voltage of 2.2V, the reflectance does not increase until the voltage reaches 2.8V. As shown in FIG. 16b, since the transmittance and the reflectance in the low light intensity section do not match, the transmittance gamma curve does not match the reflectance gamma curve. Refer to FIG. FIG. 16b is an explanatory diagram showing the relationship between transmittance and reflectance, which is a function of gamma level. The discrepancy between the gamma curves of transmittance and reflectance is a cause of degrading the image quality of the transflective liquid crystal panel.

  Accordingly, an object of the present invention is to provide a method for reducing the mismatch between the gamma curves of the transmittance and the reflectance.

  It is an object of the present invention to provide a transflective liquid crystal panel that can improve image quality.

Therefore, as a result of intensive studies in view of the drawbacks found in the prior art, the present inventor has focused on the point that the problems of the present invention can be solved by the following apparatus, and completed the present invention based on such knowledge. It was.
The present invention will be specifically described below.

Transflective liquid crystal display device according to claim 1 includes a plurality of data lines for transmitting data signals, a plurality of gate lines to provide a drive signal, in the transflective liquid crystal display device including a plurality of pixels Each of the plurality of pixels provides a switch unit that conducts a data signal of a data line according to a driving signal of a gate line, a first common electrode that provides a first common voltage signal, and a second common voltage signal A second common electrode that is electrically connected to the switch unit and electrically connected to the first common electrode and a pixel electrode that drives the liquid crystal layer in the pixel based on the conductive data signal and the first common voltage signal A first liquid crystal capacitor having a second end electrically connected to the pixel electrode, a first end electrically connected to the pixel electrode, an independent capacitor having a second end, Electrically to two common electrodes An adjustment capacitor having a second end connected to the first end connected to the second end of the independent capacitor; a first end electrically connected to the first common electrode; and a second end connected to the second end of the independent capacitor. that has a second end, conducting the data signals, the first common voltage signal, and look including a second liquid crystal capacitor for driving the liquid crystal layer based on the second common voltage signal, wherein the first liquid crystal capacitor and the One of the second liquid crystal capacitors has two electrode ends formed of a substantially transparent material, and the other of the first liquid crystal capacitor and the second liquid crystal capacitor is formed of a substantially transparent material. One electrode end and a second electrode end formed of a reflective material are included . The adjustment capacitor is provided to reduce the mismatch between the gamma curves of the transmittance and the reflectance and improve the image quality.

The transflective liquid crystal display according to claim 2 includes a storage capacitor connected in parallel to the first liquid crystal capacitor of each pixel in claim 1.

According to a third aspect of the present invention, the transflective liquid crystal display includes a storage capacitor connected in parallel to the second liquid crystal capacitor of each pixel in the first aspect.

According to a fourth aspect of the present invention, there is provided a transflective liquid crystal display that uses the power supply for providing the second common voltage signal according to the first aspect and the second common electrode of each pixel as a power supply according to the driving signal for the gate line. Including an extension switch unit to be electrically connected.

Transflective liquid crystal display device according to claim 5 is electrically connected to the second common electrode of each pixel in claim 1, comprising the additional capacity to stabilize the voltage of the second common electrode.

According to a sixth aspect of the present invention , in the transflective liquid crystal display according to the fifth aspect, the additional capacitor according to the fifth aspect includes a first end electrically connected to the second common electrode and a first end electrically connected to the first common electrode. Including two ends.

Transflective liquid crystal display device according to claim 7, both the first common voltage signal and the second common voltage signal in the claims 4, a constant voltage signal or alternating voltage signal.

The transflective liquid crystal display according to claim 8 is an AC voltage signal in which the first common voltage signal and the second common voltage signal in claim 4 have a phase difference of 180 degrees.

The transflective liquid crystal display according to claim 9 is an AC voltage signal in which the first common voltage signal and the second common voltage signal in claim 4 have the same phase.

The transflective liquid crystal display according to claim 10 is a voltage signal in which the second common voltage signal in claim 4 is constant.

Transflective liquid crystal display device according to claim 11, the first end of the first liquid crystal capacitor in claim 1 includes a first transparent electrode, the second end comprises a second transparent electrode, the second liquid crystal capacitor The first end includes a transparent electrode and the second end includes a reflective electrode.

The transflective liquid crystal display according to claim 12 is a power source for providing a second common voltage signal according to claim 11 and a second common electrode of each pixel as a power source according to a driving signal for the gate line. An expansion switch unit to be electrically connected, and an additional capacitor electrically connected to the second common electrode and stabilizing the voltage of the second common electrode.

A method for improving the image quality of the liquid crystal display of the first technology is a liquid crystal display including a first surface, a liquid crystal layer having a relative second surface, and a common electrode formed on the first surface of the liquid crystal layer. A common voltage is functionally applied to the common electrode, the liquid crystal display has a plurality of pixels, and at least a portion of the pixels has a first region having a first electrode formed on the second surface of the liquid crystal layer; A second region having a second electrode formed on a second surface of the liquid crystal layer adjacent to the first electrode, and functionally applying a first voltage to the first electrode, A first optical transmittance that is a function of the first voltage via the second electrode and a second voltage that is functionally applied to the second electrode and a second voltage that is a function of the second voltage via the second region of the liquid crystal layer. Liquid crystal display in which the first optical transmittance and the second optical transmittance are a low transmission section and a high transmission section, respectively, in two optical transmissions The second voltage is adjusted with respect to the first voltage, the high transmission section of the second optical transmittance is substantially matched with the high transmission section of the first optical transmittance, Leaving a mismatch between the low transmission interval of the two optical transmittances and the low transmission interval of the first optical transmittance, and providing a voltage to the second electrode, unlike the common voltage, via the charge storage capacitance, Reducing the discrepancy between the low transmission interval of the transmission and the low transmission interval of the first optical transmission.

In the method 2 for improving the image quality of the liquid crystal display of the technique 2, the first electrode in the technique 1 includes a transmissive electrode, and the second electrode includes a reflective electrode.

In the method 3 for improving the image quality of the liquid crystal display of the technique 3, the first optical transmittance in the technique 1 is equal to the transmittance of the liquid crystal layer through the transmissive electrode in the first region, and the second optical transmittance is the second optical transmittance. It is equal to the reflectance of the liquid crystal layer that reflects to the reflective electrode in the region.

In the technique 4 for improving the image quality of the liquid crystal display, the first voltage in the technique 2 is a data signal.

The method 5 for improving the image quality of the liquid crystal display of technology 5 has a first end where the second region in technology 4 is electrically connected to the data signal and a second end functionally connected to the reflective electrode. A charge storage capacitor is included, and the second voltage signal is a voltage signal at the second end of the charge capacitor.

A method for improving the image quality of a liquid crystal display according to a sixth aspect is a liquid crystal display including a plurality of data lines for transmitting a data signal, a plurality of gate lines for providing a driving signal, and a plurality of pixels. Each of the pixels includes a switch unit that conducts a data signal of the data line in accordance with a drive signal of the gate line, a first liquid crystal capacitor, a second liquid crystal capacitor, and a first liquid crystal capacitor connected to the switch unit. An image quality of a liquid crystal display including one end, wherein each of the pixels is electrically connected between a switch unit and a first end of a second liquid crystal capacitor, and the first liquid crystal capacitor Applying a first common voltage signal to the second end of the second liquid crystal capacitor and the second end of the second liquid crystal capacitor, and electrically connecting an adjustment capacitor between the first end of the second liquid crystal capacitor and the first voltage signal. .

The method 7 for improving the image quality of the liquid crystal display of the technology 7 further includes the step of electrically connecting the storage capacitor to the first liquid crystal capacitor in parallel with the method of the technology 6 .

The method for improving the image quality of the liquid crystal display according to the technique 8 further includes the step of electrically connecting the storage capacitor to the second liquid crystal capacitor in parallel with the method according to the technique 6 .

The method of improving the image quality of the liquid crystal display of the technology 9 is the same as the method of the technology 6 , and further, an expansion switch unit is functionally connected between the adjustment capacitor and the power source, and the expansion is performed according to the drive signal of the gate line. Including providing the regulated capacitance with a second common voltage signal of the power supply via the switch unit.

The method for improving the image quality of the liquid crystal display of the technology 10 further includes the step of electrically connecting an additional capacitor to the additional switch unit and stabilizing the voltage of the second common electrode by the method of the technology 9 .

  In the present invention, an adjustment capacitor is provided in the transflective liquid crystal display, and the mismatch between the transmittance and the reflectance curve is reduced, thereby reducing the mismatch between the gamma curve of the transmittance and the reflectance. Improve image quality.

Please refer to FIG. FIG. 1 is an explanatory diagram showing an equivalent circuit of a sub-pixel segment according to the present invention. As with the semi-transmissive liquid crystal according to the prior art, the sub-pixel segment according to the invention (m, n), the switch unit m _th
A transmission region and a reflection region are controlled by the nth gate line and the mth data line through the SW. The subpixel segment further includes a common electrode connected to the common line COM1. The optical characteristics of the liquid crystal layer in the reflective region are controlled by the reflective electrode and the common electrode. Storage C _1, after the signal current of the gate line flows, stores the charge of the sub-pixel segment.

The liquid crystal display of the present invention is a liquid crystal display including a plurality of data lines for transmitting a data signal, a plurality of gate lines for providing a driving signal, and a plurality of pixels. Switch unit m _th for conducting the data signal of the data line according to the drive signal of the gate line
SW, a first common electrode COM1 that provides a first common voltage signal, a second common electrode COM2 that provides a second common voltage signal, and a conductive data signal electrically connected to the switch unit m _th SW A pixel electrode 102 for driving the liquid crystal layer in the pixel based on the first common voltage signal, a first end electrically connected to the first common electrode COM1, and a second end electrically connected to the pixel electrode 102. a first liquid crystal capacitor C _LC1 having a first end which is electrically connected to the pixel electrode 102, an independent capacitor C _C having a second end, the first being electrically connected to the second common electrode COM2 a regulating capacitor C ₂ having a second end connected to the second end of the independent capacitance C _C to the end, the second end of the independent capacitance C _C and the end which is electrically connected to the first common electrode COM1 A connected data signal having a second end connected, the first And a second liquid crystal capacitor _CLC2 for driving the liquid crystal layer based on one common voltage signal and a second common voltage signal. The adjusting capacitance C ₂ is a discrepancy between the gamma curve of the transmittance and the reflectance is reduced, is provided to improve the image quality.

Including storage C ₁ connected in parallel the First liquid crystal capacitor C _LC1 of the pixels. The first liquid crystal capacitor C _LC1 has two electrode ends formed of a substantially transparent material, and the second liquid crystal capacitor C _LC2 is formed of a first electrode end formed of a substantially transparent material. And a second electrode end formed of a reflective material. That is, the first end of the first liquid crystal capacitor _CLC1 includes the first transparent electrode (the portion of the common electrode 25 shown in FIG. 12a), and the second end includes the second transparent electrode (the transparent electrode 54 shown in FIG. 12a). The first end of the second liquid crystal capacitor _CLC2 includes a transparent electrode (a portion of the common electrode 25 shown in FIG. 12a), and the second end includes a reflective electrode (the reflective electrode 52 shown in FIG. 12a). Alternatively, the second liquid crystal capacitor C _LC2 has two electrode ends formed of a substantially transparent material, the first liquid crystal capacitor C _LC1 includes a first end formed of a substantially transparent material, and a reflective And a second end formed of the material.

図１に示すＣＯＭ３の電圧レベルはＣＯＭ１の電圧レベルと同じようにしても良いし、ＣＯＭ１の電圧レベルと異なるようにしても良い。 As shown in FIG. 1, the first liquid crystal capacitance C _LC1 is a capacitance of the liquid crystal layer between the transparent electrode and the common electrode, and the second liquid crystal capacitance C _LC2 is a capacitance of the liquid crystal layer between the reflection electrode and the common electrode. It is. The independent capacitor C _C connected in series with C _LC2 has the effect of moving the reflectance curve of the reflective region in the high voltage direction and preventing the phenomenon of low reflectance associated with high transmittance. Adjustment capacitor C ₂ is connected between a common line n ^th COM2 of another one and the reflection electrode, thereby reducing the mismatch between the gamma curve of the gamma curve and the reflectance of the transmittance. When using an adjustment capacitance C _2, the voltage level of the reflective electrode relating to common line voltage V _COM1 is calculated by the following equation 2.
[Formula 2]

The voltage level of COM3 shown in FIG. 1 may be the same as the voltage level of COM1, or may be different from the voltage level of COM1.

Figure 2 shows a first n voltage signals _{V COM2} common line COM2, broken-line part shown in the figure shows a reference voltage level _{V REF.} The V _COM1 signal and the V _COM2 source signal of the common line COM1 are both AC signals. The V _COM1 signal has a 180 degree phase difference with the data signal on data line n, and the V _COM2 source signal has the same phase as the data signal on data line n. Since the common line COM2 is a floating electrode, the waveform of the V _COM2 source signal is determined by the V _COM1 signal and the drive mode. For example, if the drive mode is line inversion, the waveform of the V _COM2 signal is a rectangular wave as shown in FIG. In the negative voltage frame, the V _COM2 signal is generally a negative potential, but its amplitude fluctuations vary according to the waveform of the V _COM1 signal. Thereafter, when the positive voltage frame is entered by turning on the nth gate line again, the nth voltage signal _VCOM2 is refreshed and changes its polarity from negative to positive. The waveform of the nth voltage signal _VCOM2 does not change until the next frame is entered.

ΔＡ＿ＣＯＭ＝ ３Ｖとする場合（ΔＡ＿ＣＯＭはＶ_ＣＯＭ１とＶ_ＣＯＭ２間の振幅差の絶対値である）、反射率曲線と透過率曲線は図３ａに示すように一致している。図３ａに示すように、電圧４．０Ｖにおいて反射率曲線のピーク値は透過率曲線のピーク区間と重なり、電圧２Ｖ〜４Ｖの区間においては、反射率曲線と透過率曲線の傾きが近い。指数＝２．２、つまりＴ＝（ｎ／６４）^２．２の６４レベル透過率ガンマカーブを基にすれば、図３ｂに示すような反射率ガンマカーブが得られる。図に示すように、透過率ガンマカーブと反射率ガンマカーブ間の不一致は大きく低減されている。 As shown in the equation, by adjusting the values of C _C and C _2, it can improve the quality of the semi-transmissive liquid crystal panel. For example, the values of _{C C} and _{C 2} are obtained by the following formula.
[Formula 3]

If the ΔA_COM = 3V (ΔA_COM is the absolute value of the amplitude difference between _{V COM1} and _{V COM2),} the transmittance curve and the reflectivity curve is consistent as shown in Figure 3a. As shown in FIG. 3a, the peak value of the reflectance curve overlaps with the peak section of the transmittance curve at a voltage of 4.0V, and the slope of the reflectance curve and the transmittance curve is close in the section of voltage 2V to 4V. Based on a 64-level transmittance gamma curve with index = 2.2, ie T = (n / 64) ^2.2 , a reflectance gamma curve as shown in FIG. 3b is obtained. As shown in the figure, the discrepancy between the transmittance gamma curve and the reflectance gamma curve is greatly reduced.

The nth voltage signal _VCOM2 shown in FIG. 2 is used to realize the pixel inversion effect of the swing type display. Such a swing type n-th voltage signal _VCOM2 is suitable for the drive mode circuit shown in FIG. As shown in FIG. 4, the liquid crystal display according to the present invention includes a power source for providing a second common voltage signal and a second common electrode COM2 of each pixel as a power source according to a driving signal for the gate line. Expansion switch unit n _th to be connected to
SW. Further, an additional capacitor n _th C _com that is electrically connected to the second common electrode COM2 and stabilizes the voltage of the second common electrode COM2 is included. The additional capacitor n _th C _com includes a first end electrically connected to the second common electrode COM2, and a second end electrically connected to the first common electrode COM1 (COM4). Adjusting capacitance _{C 2} is added switch unit _{n th}
The nth voltage signal _VCOM2 is received by being electrically connected to the common voltage source COM2 via SW. The COM1, COM3, and COM4 shown in FIG. 4 may be the same or different. Conventionally, only one switch unit provided outside the display area is used as a device for providing the nth voltage signal _VCOM2 to the entire line n. Further, as a device for stabilizing the voltage signal of the second common electrode n ^th COM2, the switch unit n _th
A common capacitor C _COM electrically connected to SW is used. As shown in FIGS. 1 and 4, the reflection region and the transmission region of the sub-pixel segments share one storage C _1. However, as shown in FIG. 5, it is also possible to provide storage capacitors C _ST1 (C _{1 in} FIG. ₁ ) and C _ST2 in the sub-pixel segment so as to store the charges in the reflective region and the transmissive region, respectively. In addition, a constant voltage signal _VCOM2 as shown in FIG. 6 can be used instead of the swing type signal shown in FIG.

As shown in FIG. 7, as another embodiment of the present invention, a swing-type n-th voltage signal V _COM2 and a constant V _COM1 can be used simultaneously. Alternatively, as shown in FIG. 8, as another embodiment of the present invention, it is possible to set the phase difference between the signals of V _COM1 and V _COM2 and the data line n to 180 degrees and to make the phases of V _COM1 and V _COM2 the same. It is.

The adjustment capacitor can match the transmittance gamma curve and the reflectance gamma curve of an active matrix transflective liquid crystal display (AM TRLCD) without increasing the complexity of the manufacturing process. As shown in FIG. 9, adjustment capacitor is formed by adding a common line COM2 on the lower substrate, C _C and C ₂ are formed in the floating metal layer.

  A method for improving the image quality of a liquid crystal display according to the present invention is a liquid crystal display including a first surface, a liquid crystal layer having a relative second surface, and a common electrode formed on the first surface of the liquid crystal layer. A common voltage is functionally applied to the common electrode, the liquid crystal display has a plurality of pixels, and at least a portion of the pixels has a first region having a first electrode formed on the second surface of the liquid crystal layer; A second region having a second electrode formed on a second surface of the liquid crystal layer adjacent to the first electrode, and functionally applying a first voltage to the first electrode, A first optical transmittance that is a function of the first voltage via the second electrode and a second voltage that is functionally applied to the second electrode and a second voltage that is a function of the second voltage via the second region of the liquid crystal layer. Liquid crystal display in which the first optical transmittance and the second optical transmittance are a low transmission section and a high transmission section, respectively, in two optical transmissions The second voltage is adjusted with respect to the first voltage, the high transmission section of the second optical transmittance is substantially matched with the high transmission section of the first optical transmittance, Leaving a mismatch between the low transmission interval of the two optical transmittances and the low transmission interval of the first optical transmittance, and providing a voltage to the second electrode, unlike the common voltage, via the charge storage capacitance, Reducing the discrepancy between the low transmission interval of the transmission and the low transmission interval of the first optical transmission.

  The above are preferred embodiments of the present invention, and do not limit the scope of the present invention. Therefore, any modifications or changes that can be made by those skilled in the art, which are made within the spirit of the present invention and have an equivalent effect on the present invention, shall belong to the scope of the claims of the present invention. To do.

It is explanatory drawing which shows the equivalent circuit of the subpixel segment by this invention. FIG. 5 is a timing diagram showing signals of both common lines related to a gate line signal and a data line signal. In the subpixel segment of this invention, it is explanatory drawing which shows the relationship between the transmittance | permeability (T), a reflectance (R), and an applied voltage (V). In this invention, it is explanatory drawing which shows the relationship between the transmittance | permeability used as a function of a gamma level, and a reflectance. It is explanatory drawing which shows the drive voltage circuit of COM2 in the equivalent circuit of the transflective liquid crystal display of this invention. It is explanatory drawing which shows the equivalent circuit of the subpixel segment by another Example of this invention. FIG. 6 is a timing diagram showing signals of COM2 according to another embodiment of the present invention. FIG. 6 is a timing diagram showing signals COM1 and COM2 according to another embodiment of the present invention. FIG. 6 is a timing diagram showing signals COM1 and COM2 according to another embodiment of the present invention. It is sectional drawing which shows the layer structure of the lower board | substrate in the subpixel segment of the transflective liquid crystal display by this invention. It is explanatory drawing which shows the conventional liquid crystal display. It is a top view which shows the pixel structure of the conventional transflective liquid crystal display. It is sectional drawing which shows the reflected light beam and the transmitted light beam in the pixel shown in FIG. It is sectional drawing which shows the reflected light beam and the transmitted light beam in the pixel of another conventional transflective liquid crystal display. It is explanatory drawing which shows the equivalent circuit of the subpixel segment in a transflective liquid crystal display. In the conventional single-gap transflective liquid crystal panel, it is explanatory drawing which shows the relationship between the transmittance | permeability (T), reflectance (R), and applied voltage (V). It is explanatory drawing which shows the equivalent circuit of the subpixel segment in a transflective liquid crystal display. It is explanatory drawing which shows the relationship between the transmittance | permeability (T), a reflectance (R), and an applied voltage (V) in the state where the VR curve was shifted by the capacity | capacitance of the reflective area | region. It is explanatory drawing which shows the relationship between the transmittance | permeability used as a function of a gamma level, and a reflectance.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Color liquid crystal panel 10 Pixel 12R, 12G, 12B Subpixel 20 Upper board | substrate 21, 22, 23, 24 Data line 25 Common electrode 30 Lower board | substrate 31 and 32 Gate line 50 Element layer 52 Reflective electrode 54 Transparent electrode 102 Pixel electrode C _LC1 1st liquid crystal capacity C _LC2 2nd liquid crystal capacity C _C independent capacity C ₁ storage capacity C ₂ adjustment capacity C _ST1 storage capacity C _ST2 storage capacity COM common electrode COM1 first common electrode COM2 second common electrode COM3 third common electrode COM4 first Four common electrodes TA Transmission area RA Reflection area m _th SW Switch unit n _th SW Additional switch unit n _th C _com Additional capacity

Claims (12)

In a transflective liquid crystal display including a plurality of data lines for transmitting a data signal, a plurality of gate lines for providing a driving signal, and a plurality of pixels, each of the plurality of pixels serves as a driving signal for the gate line. In response, the switch unit electrically conducting the data signal of the data line, the first common electrode providing the first common voltage signal, the second common electrode providing the second common voltage signal, and the switch unit are electrically connected. A pixel electrode for driving a liquid crystal layer in the pixel based on the conducted data signal and the first common voltage signal; a first end electrically connected to the first common electrode; and a pixel electrode electrically connected to the pixel electrode A first liquid crystal capacitor having a second end; a first end electrically connected to the pixel electrode; an independent capacitor having a second end; and a first end electrically connected to the second common electrode. Connected to the second end of the capacity A regulated capacitor having a second end, a first end electrically connected to the first common electrode, and a second end connected to the second end of the independent capacitor, the conducting data signal, the first common look including a second liquid crystal capacitor for driving the liquid crystal layer based on the voltage signal, and a second common voltage signal,
One of the first liquid crystal capacitor and the second liquid crystal capacitor has two electrode ends formed of a substantially transparent material, and the other of the first liquid crystal capacitor and the second liquid crystal capacitor is substantially A transflective liquid crystal display comprising a first electrode end formed of a transparent material and a second electrode end formed of a reflective material . The transflective liquid crystal display device further includes a transflective liquid crystal display device according to claim 1, characterized in that it comprises a storage capacitance connected in parallel to the first liquid crystal capacitor of each pixel. The transflective liquid crystal display device further includes a transflective liquid crystal display device according to claim 1, characterized in that it comprises a storage capacitance connected in parallel to the second liquid crystal capacitor of each pixel.   The transflective liquid crystal display further includes a power supply for providing a second common voltage signal, and an additional switch unit for electrically connecting the second common electrode of each pixel to the power supply in accordance with a drive signal for the gate line. The transflective liquid crystal display according to claim 1, comprising:   The transflective liquid crystal display according to claim 1, further comprising an additional capacitor electrically connected to the second common electrode of each pixel and stabilizing the voltage of the second common electrode. Type liquid crystal display.   6. The transflective according to claim 5, wherein the additional capacitor includes a first end electrically connected to the second common electrode and a second end electrically connected to the first common electrode. Type liquid crystal display.   5. The transflective liquid crystal display according to claim 4, wherein each of the first common voltage signal and the second common voltage signal is a constant voltage signal or an AC voltage signal.   5. The transflective liquid crystal display according to claim 4, wherein the first common voltage signal and the second common voltage signal are alternating voltage signals having a phase difference of 180 degrees.   5. The transflective liquid crystal display according to claim 4, wherein the first common voltage signal and the second common voltage signal are alternating voltage signals having the same phase.   5. The transflective liquid crystal display according to claim 4, wherein the second common voltage signal is a constant voltage signal.   The first end of the first liquid crystal capacitor includes a first transparent electrode, the second end includes a second transparent electrode, the first end of the second liquid crystal capacitor includes a transparent electrode, and the second end includes a reflective electrode. The transflective liquid crystal display according to claim 1, further comprising:   The transflective liquid crystal display further includes a power source for providing a second common voltage signal, and an additional switch unit for electrically connecting the second common electrode of each pixel to the power source in accordance with the driving signal of the gate line. The transflective liquid crystal display according to claim 11, further comprising: an additional capacitor electrically connected to the second common electrode and stabilizing the voltage of the second common electrode.

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